Loading

Loading

Cialis Sublingual

Cialis Sublingual 20mg

By K. Grubuz. Bryan College.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government order 20 mg cialis sublingual overnight delivery. Functioning in accordance with general policies determined by the Academy purchase cialis sublingual 20mg visa, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government buy cialis sublingual 20mg on line, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards of objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We thank the following individuals for their review of this report: x Leslie Biesecker, National Institutes of Health x Martin J. Blaser, New York University Langone Medical Center x Wylie Burke, University of Washington x Christopher G. Chute, University of Minnesota and Mayo Clinic x Sean Eddy, Howard Hughes Medical Institute Janelia Farm Research x Elaine Jaffe, National Cancer Institute x Brian J. Schwartz, University of Washington Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of the report was overseen by Dennis Ausiello, Harvard Medical School, Massachusetts General Hospital and Partners Healthcare and Queta Bond, Burroughs Welcome Fund. Appointed by the National Research Council, they were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of the report rests entirely with the authoring committee and the institution. We are grateful to those who attended and participated in the workshop “Toward a New st nd Taxonomy of Disease,” held March 1 and 2 , 2011 (Appendix D) and those who discussed data sharing with the Committee during the course of this study. Kelly, Head of Informatics and Strategic Alignment, Aetna x Debra Lappin, President, Council for American Medical Innovation x Jason Lieb, Professor, Department of Biology, University of North Carolina at Chapel Hill x Klaus Lindpaintner, Vice President of R&D, Strategic Diagnostics Inc. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease Summary The Committee’s charge was to explore the feasibility and need for “a New Taxonomy of human disease based on molecular biology” and to develop a potential framework for creating one. Clearly, the motivation for this study is the explosion of molecular data on humans, particularly those associated with individual patients, and the sense that there are large, as-yet- untapped opportunities to use these data to improve health outcomes. The Committee agreed with this perspective and, indeed, came to see the challenge of developing a New Taxonomy of Disease as just one element, albeit an important one, in a truly historic set of health-related challenges and opportunities associated with the rise of data-intensive biology and rapidly expanding knowledge of the mechanisms of fundamental biological processes. Hence, many of the implications of the Committee’s findings and recommendations ramify far beyond the science of disease classification and have substantial implications for nearly all stakeholders in the vast enterprise of biomedical research and patient care. Given the scope of the Committee’s deliberations, it is appropriate to start this report by tracing the logical thread that unifies the Committee’s major findings and recommendations and connects them to its statement of task. The Committee’s charge highlights the importance of taxonomy in medicine and the potential opportunities to use molecular data to improve disease taxonomy and, thereby, health outcomes. Taxonomy is the practice and science of classification, typically considered in the context of biology (e. The Committee envisions these data repositories as essential infrastructure, necessary both for creating the New Taxonomy and, more broadly, for integrating basic biological knowledge with medical histories and health outcomes of individual patients. The Committee believes that building this infrastructure—the Information Commons and Knowledge Network—is a grand challenge that, if met, would both modernize the ways in which biomedical research is conducted and, over time, lead to dramatically improved patient care (see Figure S-1). Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease ʹ Figure S-1: Creation of a New Taxonomy first requires an “Information Commons” in which data on large populations of patients become broadly available for research use and a “Knowledge Network” that adds value to these data by highlighting their interconnectedness and integrating them with evolving knowledge of fundamental biological processes. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease ͵ The Committee envisions this ambitious program, which would play out on a time scale of decades rather than years, as proceeding through a blend of top-down and bottom-up activity. A major top-down component, initiated by public and private agencies that fund and regulate biomedical research, would be required to insure that results of individual projects could be combined to create a broadly useful and accessible Information Commons and to establish guidelines for handling the innumerable social, ethical, and legal issues that will arise as data on individual patients become widely shared research resources. However, as is appropriate for a framework study, the Committee did not attempt to design the Information Commons, the Knowledge Network, or the New Taxonomy itself and would discourage funding agencies from over-specifying these entities in advance of initial efforts to create them. What is needed, in the Committee’s view, is a creative period of bottom-up research activity, organized through pilot projects of increasing scope and scale, from which the Committee is confident best practices would emerge. Particularly given the size and diversity of the health-care enterprise, no one approach to gathering the data that will populate the Information Commons is likely to be appropriate for all contributors. As in any initiative of this complexity, what will be needed is the right level of coordination and encouragement of the many players who will need to cooperate to create the Information Commons and Knowledge Network and thereby develop a New Taxonomy. If coordination is too rigid, much-needed innovation and adaptation to local circumstances will be stifled, while if it is too lax, it will be impossible to integrate the data that are gathered into a whole whose value greatly exceeds that of the sum of its parts, an objective the Committee believes is achievable with effective central leadership. Conclusions The Committee hosted a two day workshop that convened diverse experts in both basic and clinical disease biology to address the feasibility, need, scope, impact, and consequences of creating a “New Taxonomy of human diseases based on molecular biology”. The information and opinions conveyed at the workshop informed and influenced an intensive series of Committee deliberations (in person and by teleconference) over a 6 month period, which led to the following conclusions: 1. Because new information and concepts from biomedical research cannot be optimally incorporated into the disease taxonomy of today, opportunities to define diseases more precisely and to inform health care decisions are being missed. Many disease subtypes with distinct molecular causes are still classified as one disease and, conversely, multiple different diseases share a common molecular cause. The failure to incorporate optimally new biological insights results in delayed adoption of new practice guidelines and wasteful health care expenditures for treatments that are only effective in specific subgroups. Dramatic advances in molecular biology have enabled rapid, comprehensive and cost efficient analysis of clinical samples, resulting in an explosion of disease-relevant data with the potential to dramatically alter disease classification. Fundamental discovery research is defining at the molecular level the processes that define and drive physiology. These developments, coupled with parallel advances in information technologies and electronic medical records, provide a transformative opportunity to create a new system to classify disease. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 4 3. A New Taxonomy that integrates multi-parameter molecular data with clinical data, environmental data, and health outcomes in a dynamic, iterative fashion, is feasible and should be developed. The Committee envisions a comprehensive disease taxonomy that brings the biomedical-research, public-health, and health-care-delivery communities together around the related goals of advancing our understanding of disease pathogenesis and improving health. Such a New Taxonomy would x Describe and define diseases based on their intrinsic biology in addition to traditional physical “signs and symptoms. The informational infrastructure required to create a New Taxonomy with the characteristics described above overlaps with that required to modernize many other facets of biomedical research and patient care. This infrastructure requires an “Information Commons” in which data on large populations of patients become broadly available for research use and a “Knowledge Network” that adds value to these data by highlighting their interconnectedness and integrating them with evolving knowledge of fundamental biological processes. New models for population-based research will enable development of the Knowledge Network and New Taxonomy. Current population-based studies of disease are relatively inefficient and can generate conclusions that are not relevant to broader populations. Widespread incorporation of electronic medical records into the health-care system will make it possible to conduct such research at “point-of-care” in conjunction with the routine delivery of medical services. Moreover, only if the linked phenotypic data is acquired in the ordinary course of clinical care is it likely to be economically feasible to characterize a sufficient number of patients and ultimately to create a self-sustaining system (i. Redirection of resources could facilitate development of the Knowledge Network of Disease. The initiative to develop a New Taxonomy—and its underlying Information Commons and Knowledge Network—is a needed modernization of current approaches to integrating molecular, environmental, and phenotypic data, not an “add-on” to existing research programs. Enormous efforts are already underway to achieve many of the goals of this report. In the Committee’s view, what is missing is a system-wide emphasis on shifting the large-scale acquisition of molecular data to point-of-care settings and the coordination required to insure that the products of the research will coalesce into an Information Commons and Knowledge Network from which a New Taxonomy (and many other benefits) can be derived. In view of this conclusion, the Committee makes no recommendations about the resource requirements of the new-taxonomy initiative. Obviously, the process could be accelerated with new resources; however, the basic thrust of the Committee’s recommendations could be pursued by redirection of resources already dedicated to increasing the medical utility of large-scale molecular data-sets on individual patients. Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease 5 Recommendations To create a New Taxonomy and its underlying Information Commons and Knowledge Network, the Committee recommends the following: 1. Pilot observational studies should be conducted in the heath care setting to assess the feasibility of integrating molecular parameters with medical histories and health outcomes in the ordinary course of clinical care. These studies would address the practical and ethical challenges involved in creating, linking, and making broadly accessible the datasets that would underlie the New Taxonomy. Best practices defined by the pilot studies should then be expanded in scope and scale to produce an Information Commons and Knowledge Network that are adequately powered to support a New Taxonomy. As this process evolves, there should be ongoing assessment of the extent to which these new informational resources actually contribute to improved health outcomes and to more cost effective delivery of health care. As data from point-of- care pilot studies, linked to individual patients, begin to populate the Information Commons, substantial effort should go into integrating these data with the results of basic biomedical research in order to create a dynamic, interactive Knowledge Network. This network, and the Information Commons itself, should leverage state-of-the-art information technology to provide multiple views of the data, as appropriate to the varying needs of different users (e. Initiate a process within an appropriate federal agency to assess the privacy issues associated with the research required to create the Information Commons. Because these issues have been studied extensively, this process need not start from scratch. However, in practical terms, investigators who wish to participate in the pilot studies discussed above—and the Institutional Review Boards who must approve their human- subjects protocols— will need specific guidance on the range of informed-consent processes appropriate for these projects. Subject to the constraints of current law and prevailing ethical standards, the Committee encourages as much flexibility as possible the guidance provided. As much as possible, on-the-ground experience in pilot projects carried out in diverse health-care settings, rather than top-down dictates, should govern the emergence of best practices in this sensitive area, whose handling will have a make- or-break influence on the entire information-commons/knowledge-network/new- taxonomy initiative. Inclusion in these deliberations of health-care providers, payers, and other stakeholders outside the academic community will be essential. Widespread data sharing is critical to the success of each stage of the process by which the Committee envisions creating a New Taxonomy.

In deriving the protein requirement generic cialis sublingual 20 mg free shipping, this estimate of miscellaneous losses was included as an adjustment to the reported nitrogen balances for the studies included in Table 10-8 purchase 20 mg cialis sublingual with mastercard. The miscellaneous losses from both boys and girls are assumed to be the same since data from girls were limited generic 20 mg cialis sublingual with amex. Individual maintenance protein require- ments were estimated by first regressing nitrogen balance on nitrogen intake for the individuals studied at several different intake levels, and then using these individual regression equations to interpolate the intakes that would be expected to produce zero nitrogen balance (adjusting for 6. Table 10-8 contains seven studies that permit estimation of individual requirements and three studies that were used to estimate pooled requirements. As shown in the table, the average individual maintenance requirement was estimated as the median of the individual nitrogen requirements (108 mg/kg/d). For each study, an estimate was calculated as the median of the individual studies or the study pooled nitrogen requirement for those studies without individual data, and was 110 mg/kg/d. Since data for girls were sparse and could not be separated from that for boys, the protein maintenance requirement for both boys and girls is set at the same level. In addition, the maintenance protein requirement was not adjusted for age, as the requirement per kg of body weight for children 8 years of age and above appeared to be simi- lar to that of younger children ranging in age from 9 months to 5 years (Table 10-8). Supporting this decision are the data of Widdowson and Dickerson (1964), which demonstrated that around 4 years of age, body protein concentration reaches the adult value of 18 to 19 percent of body weight. Estimates of rates of protein deposition for infants from 9 months through 3 years of age (Butte et al. To obtain protein deposition rates since the data in young children were longitudinal (Butte et al. The gradients at specific ages in the range 4 through 17 years were determined by differentiation of the regression equation. Hence, the gradients at specific ages in the age range 4 through 18 years were determined by differentiation of the regression equation, whereas for ages 9 months through 2 years, the growth rates given by Butte and coworkers (2000) were employed. The variation in requirements is based on both the variation in maintenance needs and the variation in the rate of protein deposition (protein for growth). Median requirement for ages 14 through 18 years = 656 mg protein/kg/d (105 mg N/kg/d [Table 10-12] × 6. A coefficient of variation for growth of 43 percent was determined in a study of whole body potassium-40 content in children (Butte et al. The mean of the nitrogen intake for nitrogen equilibrium (thus measur- ing maintenance requirement only) is derived from all of the individual estimates for children and is 110 mg nitrogen/kg/d or 688 mg protein/kg/d (110 × 6. This is multiplied by the mean protein deposition (Table 10-9) for boys and for girls for each age group. While the nitrogen balance method for estimation of protein requirements has serious shortcomings (see “Nitrogen Balance Method”), this method remains the primary approach for determining the protein requirement in adults, in large part because there is no validated or accepted alternative. Nitrogen Balance Studies Over the last 40 years, a number of analyses of available data on adult nitrogen balance studies have been utilized to estimate adult protein require- ments; some reports are listed in Table 10-10. This was considered important so that estimates of individual require- ments could be interpolated. In addition, 9 studies of individuals fed a single level of nitrogen intake or that only provided group data for multiple levels of intake (n = 174 individuals) were used to assess the fit of the analyses conducted (Rand et al. The studies used were classified on the basis of age of the adults (young: 19 through 52 years of age; old: 53 years of age and older); protein source (animal [animal sources provided > 90 percent of the total protein], vegetable [vegetable sources provided > 90 percent of the total protein], or mixed), as well as gender and climatic origin (temperate or tropical area), and corrected for skin and miscellaneous losses when not included in the nitrogen balance data (Rand et al. Estimates of endogenous loss from some of the various analyses of protein requirements are included in Table 10-11. However, as discussed in earlier sections, the effi- ciency of utilization of dietary protein declines as nitrogen equilibrium is reached. With additional data it is possible to estimate requirements using regression analysis. Linear regression of nitrogen balance on nitrogen intake was utilized to estimate the nitrogen intake that would produce zero nitrogen balance in the most recent carefully done analysis available (Rand et al. In adults, it is generally presumed that the protein requirement is achieved when an individual is in zero nitrogen balance. To some extent, this assumption poses problems that may lead to under- estimates of the true protein requirement (see “Nitrogen Balance Method”). In this range there is no indication, either visually or statistically, for the utilization of an interpolation scheme other than linear (Rand et al. It was also recognized that while the use of more complex models would improve the standard error of fit, these models did not statistically improve the fits, in large part because of the small number of data points (3 to 6) for each individual (Rand et al. Estimation of the Median Requirement Utilizing the recent analysis of nitrogen balance data (Rand et al. Because of the non-normality of the individual data, nonparametric tests were used (Mann-Whitney and Kruskal-Wallis) to compare requirements between the age, gender, diet, and climate subgroups (Table 10-13). Where nonsignifi- cant differences were found, Analysis of Variance was used for power cal- culations to roughly estimate the differences that could have been found with the data and variability. Statistical Analysis of Nitrogen Balance Data to Determine the Protein Requirement Data Analysis. The relationship between nitrogen balances, corrected for integumental and miscellaneous losses, and nitrogen intake from Rand and coworkers (2003) is shown in Figure 10-6. This figure includes indi- vidual data from the linear regression of nitrogen balance in adults exam- ined (Rand et al. The authors noted that positive nitrogen balance was found in some individuals at nitrogen intakes as low as 60 mg/kg/d, and in other individuals negative balance was noted at nitrogen intakes as high as 200 mg/kg/d. This suggests that at least some of these individuals were not at constant nitrogen balance equilibrium. In addition, while the nitrogen balance response to increasing nitrogen intake is theoretically expected to be nonlinear, the primary individual data points near the equilibrium balance point demonstrate a linear rela- tionship, which appears to become nonlinear at high intakes. This can be attributed to different study designs in the test data included in Figure 10-6. The data points from only the estimation studies show a linear response over the relatively narrow range of intakes studied, while data points from the test studies also show a response that is not different from linear, although more variable and with a lower slope. Much variability is noted in the response data because the studies differ in methodology, individuals differ from each other, and an individual’s response differs from day to day. Table 10-12, a summary of the nitrogen requirement for all the data points included in the analysis by Rand and coworkers (2003), shows a nitrogen requirement of 105 mg/kg/d or 0. When only the indi- vidual data points in the primary estimation studies are considered, the nitrogen requirement is 102 mg/kg/d (0. As shown in Table 10-13, expected climate in the country of the study had a significant effect (p < 0. The effect of age, as shown in Table 10-13, was a nonsignificant difference of 27 mg N/d (0. Although the young individuals had a lower nitrogen require- ment than the older individuals, the requirement of young individuals was more variable and more positively skewed than that for the older individuals. Ninety-five percent confidence intervals for these estimates are 104 and 114 mg N/kg/d (0. Finally, the source of protein (90 percent animal, 90 percent vegetable, or mixed) did not significantly affect the median nitrogen requirement, slope, or intercept. It should be noted that almost all of the studies included as 90 percent vegetable were based on complementary proteins. For further discussion on this aspect of the data analysis and for information on vegetarian diets see later sections on “Protein Quality” and on “Vegetarians. Other Approaches to Determine the Protein Requirement Based on the Recent Meta-Analysis In addition to the linear statistical approach to determine protein requirements described in detail above, the authors considered three other statistical approaches to the nitrogen balance analysis (Rand et al. All data from the studies in the meta-analysis were fitted to the following models: linear, quadratic, asymptotic exponential growth and linear biphase (see Table 10-12). Since the above analyses used all of the available data points without linking the individuals or restricting the range of intakes, the authors made the decision to use nitrogen equilibrium as the criterion and individual linear regressions, using only those individuals in the primary data set to determine the protein requirement (Rand et al. However, due to the shortcomings of the nitrogen balance method noted earlier, it is rec- ommended that the use of nitrogen balance should no longer be regarded as the “gold standard” for the assessment of the adequacy of protein intake and that alternative means should be sought. Although the data indicate that women have a lower nitrogen require- ment than men per kilogram of body weight, this was only statistically significant when all studies were included, but not when the analysis was restricted to the primary data sets. This difference may be due to differ- ences in body composition between men and women, with women and men having on average 28 and 15 percent fat mass, respectively. When controlled for lean body mass, no gender differences in the protein re- quirements were found. For example, the intake that is estimated to be adequate for 80 per- cent of a healthy population is exp [0. Because the distribution of individual requirements for protein is log normal, and thus skewed, the calculated standard deviation and coeffi- cient of variation of requirement itself does not have the usual intuitive meaning (that the mean plus two standard deviations exceeds all but about 2. However, because this skew- ing is not extreme, an approximate standard deviation can be calculated as half the distance from the 16th to the 84th percentile of the protein requirement distribution as estimated from the log normal distribution of requirements. These have been analyzed and evaluated in various publications (Campbell and Evans, 1996; Campbell et al. The variability among the derived values, and the changes due to reassessment, are the result of the many inadequacies in the origi- nal data, which are described below. Only the study of Cheng and coworkers (1978) involved a direct com- parison of old with young adults; however, the authors made no assess- ment of the miscellaneous nitrogen losses and were not able to show any clear difference in the requirement of older and younger adults. Dietary energy excess is believed to give rise to erroneously low esti- mates of protein requirements (Garza et al. However, the energy requirements of the elderly have been shown to be higher than previously believed (Roberts, 1996). Moreover, the urinary creatinine to body weight ratio reported by Cheng and coworkers (1978) was the same in the old (0.

generic 20mg cialis sublingual mastercard

The limits to life expectancy and and health conditions is one key to holding lifespan are not as obvious as once thought order cialis sublingual 20 mg with visa. The health And there is mounting evidence from cross- and economic burden of disability also can national data that—with appropriate policies be reinforced or alleviated by environmental and programs—people can remain healthy characteristics that can determine whether and independent well into old age and can an older person can remain independent continue to contribute to their communities despite physical limitations cialis sublingual 20mg cheap. Prevalence of dementia rises and ill health in developing countries will be sharply with age cheap cialis sublingual 20 mg online. An estimated 25-30 percent entering old age in coming decades, potentially of people aged 85 or older have dementia. Aging is taking place alongside other broad social trends that will affect the lives of older people. Economies are globalizing, people are more likely to live in cities, and technology is evolving rapidly. Demographic and family changes mean there will be fewer older people with families to care for them. People today have fewer children, are less likely to be married, and are less likely to live with older generations. By 2050, this number is expected to fell with surprising speed in many less developed nearly triple to about 1. Between 2010 and 2050, the number of older Most developed nations have had decades to people in less developed countries is projected to adjust to their changing age structures. In contrast, many less This remarkable phenomenon is being driven developed countries are experiencing a rapid by declines in fertility and improvements in increase in the number and percentage of older longevity. With fewer children entering the people, often within a single generation (Figure population and people living longer, older 2). For example, the same demographic aging people are making up an increasing share of the that unfolded over more than a century in total population. The Speed of Population Aging Time required or expected for percentage of population aged 65 and over to rise from 7 percent to 14 percent Source: Kinsella K, He W. In some countries, the sheer number of people entering older ages will challenge national infrastructures, particularly health systems. By the middle of this century, there could be 100 million Chinese over the age of 80. This is an amazing achievement considering that there were fewer than 14 million people this age on the entire planet just a century ago. Growth of the Population Aged 65 and Older in India and China: 2010-2050 Source: United Nations. Humanity’s Aging 5 Living Longer The dramatic increase in average life expectancy pathways. Less developed to noncommunicable diseases and chronic regions of the world have experienced a steady conditions. Even These improvements are part of a major earlier, better living standards, especially transition in human health spreading around more nutritious diets and cleaner drinking the globe at different rates and along different water, began to reduce serious infections and prevent deaths among children. Research for more recent periods shows a surprising and continuing improvement in life expectancy among those aged 80 or above. The progressive increase in survival in these oldest age groups was not anticipated by demographers, and it raises questions about how high the average life expectancy can realistically rise and about the potential length of the human lifespan. While some experts assume that life expectancy must be approaching an upper limit, 6 Global Health and Aging Figure 4. Living Longer 7 data on life expectancies between 1840 and 2007 global level, the 85-and-over population is show a steady increase averaging about three projected to increase 351 percent between 2010 months of life per year. The country with the and 2050, compared to a 188 percent increase for highest average life expectancy has varied over the population aged 65 or older and a 22 percent time (Figure 4). So far there is little evidence that life to increase 10-fold between 2010 and 2050. In many decreases in mortality rates among the oldest countries, the oldest old are now the fastest old. Percentage Change in the World’s Population by Age: 2010-2050 Source: United Nations, World Population Prospects: The 2010 Revision. Demographers and epidemiologists describe this Evidence from the multicountry Global Burden shift as part of an “epidemiologic transition” of Disease project and other international characterized by the waning of infectious and epidemiologic research shows that health acute diseases and the emerging importance of problems associated with wealthy and aged chronic and degenerative diseases. High death populations affect a wide and expanding rates from infectious diseases are commonly swath of world population. Over the next associated with the poverty, poor diets, and 10 to 15 years, people in every world region limited infrastructure found in developing will suffer more death and disability from countries. Although many developing countries such noncommunicable diseases as heart still experience high child mortality from disease, cancer, and diabetes than from infectious and parasitic diseases, one of the Figure 6. The Increasing Burden of Chronic Noncommunicable Diseases: 2008 and 2030 Source: World Health Organization, Projections of Mortality and Burden of Disease, 2004-2030. In direct bearing on the development of risk factors for 2008, noncommunicable diseases accounted for an adult diseases—especially cardiovascular diseases. Among the impairments or physical limitations at ages 80 or 60-and-over population, noncommunicable diseases older. Proving links between childhood health conditions But the continuing health threats from and adult development and health is a complicated communicable diseases for older people cannot research challenge. Older people account for a necessary to separate the health effects of changes growing share of the infectious disease burden in in living standards or environmental conditions low-income countries. However, older people and ignore the potential effects of a Swedish study with excellent historical data population aging. And, there is growing evidence A cross-national investigation of data from two that older people are particularly susceptible surveys of older populations in Latin America to infectious diseases for a variety of reasons, and the Caribbean also found links between early including immunosenescence (the progressive conditions and later disability. The older people in deterioration of immune function with age) the studies were born and grew up during times and frailty. Older people already suffering from of generally poor nutrition and higher risk of one chronic or infectious disease are especially exposure to infectious diseases. For survey, the probability of being disabled was more example, type 2 diabetes and tuberculosis are well- than 64 percent higher for people growing up in known “comorbid risk factors” that have serious health consequences for older people. A survey of seven urban centers in Latin counterparts in the developed world, and studies America and the Caribbean found the probability such as those described above suggest that they are of disability was 43 percent higher for those from at much greater risk of health problems in older age, disadvantaged backgrounds than for those from more often from multiple noncommunicable diseases. People now growing old in low- and middle- diet, and physical activity may have long-term health income countries are likely to have experienced more implications. Probability of Being Disabled among Elderly in Seven Cities of Latin America and the Caribbean (2000) and Puerto Rico (2002-2003) by Early Life Conditions Source: Monteverde M, Norohna K, Palloni A. Effect of early conditions on disability among the elderly in Latin-America and the Caribbean. New Disease Patterns 11 Longer Lives and Disability Are we living healthier as well as longer lives, or forward. National Institutes of Health, found among researchers, and the answers have broad surprising health differences, for example, implications for the growing number of older between non-Hispanic whites aged 55 to 64 people around the world. In general, the question is to look at changes in rates of people in higher socioeconomic levels have better disability, one measure of health and function. In the United States, between 1982 in education and behavioral risk factors (such as and 2001 severe disability fell about 25 percent smoking, obesity, and alcohol use) explained few among those aged 65 or older even as life of the health differences. With the levels of wealth, Americans were less healthy rapid growth of older populations throughout than their European counterparts. Analyses of the world—and the high costs of managing the same data sources also showed that cognitive people with disabilities—continuing and better functioning declined further between ages 55 and assessment of trends in disability in different 65 in countries where workers left the labor force countries will help researchers discover more at early ages, suggesting that engagement in about why there are such differences across work might help preserve cognitive functioning. American Journal of Public Health 2009; 99/3:540-548, using data from the Health and Retirement Study, the English Longitudinal Study of Ageing, and the Survey of Health, Ageing and Retirement in Europe. Dementia prevalence estimates vary considerably internationally, in part because diagnoses and reporting systems are not standardized. The memory problems, misunderstandings, and behavior common in the early and intermediate stages are often attributed to normal effects of aging, accepted as personality traits, or simply ignored. The Growth of Numbers of People with Dementia in High- income Countries and Low- and Middle-income Countries: 2010-2050 Source: Alzheimer’s Disease International, World Alzheimer Report, 2010. In addition to myriad demographic and In light of this, the organization mounted a socioeconomic characteristics, the study collects multicountry longitudinal study designed to data on risk factors, health exams, and biomarkers. Overall Health Status Score in Six Countries for Males and Females: Circa 2009 Notes: Health score ranges from 0 (worst health) to 100 (best health) and is a composite measure derived from 16 functioning questions using item response theory. Researchers derive a composite age, but the patterns and the percentages measure from responses to 16 questions about vary by country (Figure 11). In each country, the declining prevalence of co-residence by multiple health status score declines with age, as expected. Percentage of Adults with Three or More Major Risk Factors: Circa 2009 60% 50% 40% 30% 20% 10% 0% 18-49 50-59 60-69 70-79 80+ Age Group Notes: Major risk factors include physical inactivity, current tobacco use, heavy alcohol consump- tion, a high-risk waist-hip ratio, hypertension, and obesity. If rising hypertension rates in in the technological capabilities of medicine those populations are not adequately addressed, generally play a much larger role. Percentage of Women with Moderate or Severe Hypertension in Six Countries: Circa 2009 50% 40% 30% 20% 10% 0% 18-49 50-59 60-69 70-79 80+ Age Group Note: National data collections conducted during the period 2007-2010. Early detection older ages, the high cost of prolonging life is shifted and effective management of risk factors such as to ever-older ages. In many societies, the nature hypertension—and other important conditions and extent of medical treatment at very old ages such as diabetes, which can greatly complicate the is a contentious issue. However, data from the treatment of cardiovascular disease—in developing United States suggest that health care spending at countries can be inexpensive and effective ways of the end of life is not increasing any more rapidly controlling future health care costs. Also needed are studies of comparative performance or comparative effectiveness in low-income countries of various treatments and interventions. The Costs of Cardiovascular Disease and Cancer In high-income countries, heart disease, stroke, estimated loss in economic output for the 23 and cancer have long been the leading contributors nations as a whole between 2006 and 2015 totaled to the overall disease burden. The potential Assessing the Costs of Aging and Health Care 19 Health and Work In the developed world, older people often Other than the economic incentives of leave the formal workforce in their later years, pensions, what would make people stay in the although they may continue to contribute to workforce longer?

order cialis sublingual 20 mg

Confict resolution requires please us: “It would be helpful for me… What a genuine desire to understand buy discount cialis sublingual 20 mg line. It involves a commitment to would work for me is…” (McKay et al 1995) engage in problem-solving with the other party generic 20mg cialis sublingual, and requires ground rules that permit open exchange and reduces the need for defensiveness order 20 mg cialis sublingual mastercard. Fortunately, resisting the urge to respond defensively is a skill that can be learned. Viewing the confict as a problem to be solved mutually so that both parties feel that Key references they are benefting from the resolution is the goal of collabora- Lindahl K and A Schnapper. No relationship can be long-lasting Forty Refections for Cultivating a Spiritual Practice. It is not unusual for these physicians to be highly response to situations involving disruptive behaviour. They commonly see themselves Case as superior to others in their clinical competence and insist The chief resident in internal medicine has arranged to that others submit to their way of doing things. The resident doesn’t come to teaching sessions, doesn’t show up for clinics on time, is always late when Causes showing up for on-call responsibilities and therefore never There is no single cause of disruptive behaviour. The it is not generally associated with substance use disorders, other residents are complaining to the chief. The nurses other underlying physician health issues such as stress and on the ward and the emergency room staff have started burnout can be contributing factors. The been associated with certain personality characteristics such chief wants something to be done. It is often a result of an inability to deal The term “disruptive doctor” is often thought of in relation to with the confict inevitable in the face of stressful work envi- physicians who demonstrate a pattern of offensive or objec- ronments and rapid change. Indeed, disruptive behaviour can tionable behaviour, such as berating staff in front of patients be a sign of failure within a system, where confict has become or using intimidation tactics when supervising residents. The focus is often exclusively Many defnitions have been developed to describe disruptive on the individual’s behaviour, to the exclusion of any examina- behaviour. But focusing solely on changing defnes it as follows: “Disruptive behaviour is demonstrated the physician’s behaviour is not productive. It is also vital when inappropriate conduct, whether in words or action, to examine systemic factors in, and responses to, disruptive interferes with, or has the potential to interfere with, quality behaviour. Disruptive behaviour has negative consequences both for the But is it clear that physicians themselves must show leadership delivery of patient care and for the smooth running of medical in addressing disruptive behaviour in their practice settings departments. The issue should be approached and other adverse events, and has the potential to stife the even-handedly, taking logical steps. First, what constitutes respectful collaboration and interdisciplinary collegiality that disruptive behaviour needs to be clearly defned and its impact are crucial to effective care delivery in today’s complex health understood. The development of a professional code of conduct to address workplace interpersonal behaviour is also important. It states: When the chief resident becomes aware of a resident who “To satisfy our mission, all members of the medical is not meeting their responsibilities, the chief confrms and health staff will treat patients, staff and fellow the facts and meets with the resident to notify them of physicians in a dignifed manner that conveys respect the concern and discuss the issue. The chief obtains a for the abilities of each other and a willingness to work commitment that the behaviour will not be repeated. Behaviour that is deemed to be disruptive to chief then follows up to monitor future behaviour know- promoting an atmosphere of collegiality, cooperation, ing that future trangressions will need to be brought to the and professionalism will not be tolerated. The program director must ensure there is a policy or guidelines on the expectations Although one might feel that formalizing such a code of about professional responsibility. Such a code has a preventative role duct boundaries for physicians returning to the workplace after as well; it can help create a culture of respect and collegiality a confict arising from disruptive behaviour, it is wise to involve by offering guiding principles for all who work in the institu- the physician concerned. The code should be consistent with the philosophy of the organization’s code of conduct, policies and procedures, to the larger organization, or could be the same code used by all ensure that the physician returning is clear on the expectations providers in the organization. After a return to work, consistent monitoring and reinforcement of appropriate behaviours will be critical to Even with an agreed-upon code of conduct, it can often ap- ensuring that change is lasting. Therefore, a clearly defned set of policies and Summary procedures that everyone is familiar with should also be devel- The appropriate approach to this issue should be one of reha- oped. Like the code of conduct, these policies and procedures bilitation and support rather than punishment. They organizations need to clarify their defnition of disruptive pro- need to be developed through consultation and consensus; to fessional behaviour. Leaders must appreciate what contributes be credible, this should involve the “grass roots. It is no longer acceptable to rely expectations, and monitoring conduct after assessment or on the “professionalism” lectures that were provided early treatment. Ensuring that orientation to the code of conduct and policies The medical staff organization will usually need the support and procedures occurs on receipt of hospital privileges or and collaboration of the medical administration to ensure that employment can prevent problems down the road. At the end of the day, an approach to disruptive behaviour that is fair, consistent, timely It should be stressed that if administrative physicians were to and understood by all within the organization should be the hurriedly write a unilateral code of conduct or policies and goal. Born between roughly 1960 and 1980, this This chapter will cohort is also known as the “Me Generation” and the “Lost • describe key differences between generation Y, generation Generation. Gen X also came to age in an era of instabil- • identify key areas in which generational differences can ity in Canadian medicine, when a lack of professional unity contribute to confict, and consider the unique opportuni- contributed to tensions around billing number restrictions, ties presented by today’s generational mix for the practice loss of training fexibility, and early-career decision-making. They will A mid-career physician in a busy academic hospital enjoys work hard, but demand negotiation, respect and clarity in order working with residents and values the unique perspectives to protect the balance between their personal and professional and energies they bring to clinical and academic work. However, the physician is increasingly concerned by what feels like a slippage of professional duty, commitment and Baby boomers. On rounds, the physician expressed dissatisfac- Boomer cohort is highly focused on professional success and tion with a medical student who was playing with her competition, productivity and output, and respect for tradi- phone, a resident who was not wearing a tie, and a fellow tional hierarchy and roles. Known to roll up their sleeves and who indicated he needed to leave by 5 o’clock to pick his pitch in, they are more prone to sacrifce themselves to realize daughter up for a soccer game. Their rates of burnout are high made a complaint about this behaviour to the site director (up to 42 per cent in Canada), as are their rates of divorce or for education. Born generally before the mid-1940s, this The Canadian medical community embraces a diverse mix senior cohort of physicians has a wealth of experience and tal- of learners and practitioners. Many have now retired from active practice but have had including gender, race, cultural heritage, political alliance a profound and valuable infuence on traditional structures in and philosophical world view. One facet of diversity that is medicine, including practice standards, training methodology becoming increasingly relevant to educational programs is that and professionalism. Obviously, any framework that clusters diverse people into specifc categories is at risk of overgeneralizing; Sources of tension however, the following sketches of today’s generations and The varying experiences and expectations of these generational their traits may be a useful way to conceptualize challenges cohorts can give rise to misunderstandings and tensions arising that arise in training and practice environments. This cohort generally consists of the popula- tion born from the early 1980s to the early 2000s. Boomers and Gen X/Y as the millennial generation and the “net” generation, this seem to be most at risk of confict in this area, as their perspec- cohort came of age in a time of political stability, economic tives are often very different. Regardless of the nature of the advantage and particular encouragement and support. Boomers need to facilitate embrace digital communication and are skilled multi-taskers learning and practice environments that sustain learners while who are not insulted when someone does a Google search on preparing them for the rigours of practice. This is not a par- their iPhone in mid-conversation, responds to an urgent text ticularly easy task and requires careful mentoring, graduated message during small group learning, or accesses the latest responsibility, respect for boundaries/limits, and acknowledge- clinical information through their Blackberry. Finally, they are ment of collective agreements and respectful interpersonal often image-driven, favour self-expression over self-control, communication. They work hard to get a job done but do so in a highly fexible manner and on their own terms. Multi-tasking is • mentored in a supportive, non-judgmental fashion to often viewed with disdain by Boomers, particularly when they achieve their best, manage their weaknesses, gain witness learners communicating with more than one person insight into their own nature and progress to the next at the same time (e. Aspects of multi-tasking require open • consulted on any decisions that will affect them in a discussion and dialogue, as well as fexibility: the X and Y manner that acknowledges that their ideas may be part generations are often able to safely divide their attention across of a solution rather than part of a problem; and multiple domains and do so with no intention of disrespect or • connected to their peers, supervisors, families, disregard. The shift in contemporary culture away from hierarchical expectations in social relation- With fexibility, a sense of humour, honesty and transparency, ships is notable. Respect from others no longer follows auto- all generations can readily engage one another to solve almost matically from a position of authority; rather, it is earned and any challenge they face. Younger generations need to be sensitive to the culture of their more senior col- Case resolution leagues, while Boomers and traditionalists will gain points by The physician attended a seminar on intergenerational demonstrating principles of equity, respect and autonomy. In opportunities and realized that many of the behaviours addition, younger cohorts need to be reminded, often through interpreted as disrespectful were, in fact, the opposite. The physician shortage of physicians in Canada, and many Gen Xers (and, also refected on the healthy boundaries the students set very soon, Gen Ys) will soon be moving into leadership po- between personal and professional life and the physician sitions in education and practice. In the past, Boomers and began to make changes in their own practice in order to traditionalists earned such positions after “paying their dues,” spend time with family and signifcant others. Finally, the learning on the job and having time to develop readiness for physician purchased a smartphone and, after a tutorial leadership. More than ever before, younger generations need with a medical student, found that it improved effciency mentorship and support from more experienced colleagues as remarkably. The more open and fexible the physician they take on heavy responsibilities early in their career. In fact, intergenerational diversity brings with it a Key references remarkable opportunity to integrate and synergize perspectives Smith W. Messages for the learning and practice environment Puddester D, Gray C, Robertson C. Training generation When managing or preventing the many conficts that can arise x: A theme of growing importance. Royal College Outlook 2:1 in an intergenerational training or practice environment, it can Spring; 8–10. The American College of Physicians manual • describe factors that infuence working relationships with states: other health care professionals, peers and faculty; and “Physicians share their commitment to care for all ill • identify steps that can be taken to improve collegiality. The team’s ability to care effectively for the patient depends on the ability of individual persons to treat each other with Case integrity, honesty and respect. Particular attention must be A frst-year resident working in a major urban hospital paid to certain types of relationships and power imbalances is fve months pregnant when she does her rotation and […] such as attending physician and resident, resident and fnds that the nurses are very kind to her. One night Murray Goldstein states this idea more simply “[c]ollegiality while she is on call a woman in labour begins to show signs requires a fostering of the attitude ‘we are in this together’.

Low Birth Weight Rush and coworkers (1980) found decreases in both gestational length and birth weight and increases in very early premature births and mortal- ity with high density protein supplementation (additional 40 g/d) in poor order cialis sublingual 20 mg with amex, black pregnant women at risk of having low birth weight infants order cialis sublingual 20 mg with visa. In contrast buy cialis sublingual 20mg mastercard, Adams and coworkers (1978) reported no differences from the controls in mean birth weights of infants of mothers at risk of having a low birth weight infant when these women were supplemented with 40 g/d of protein. No reports were found of protein toxicity in healthy pregnant or lactating women that were not at risk of having a low birth weight infant. Risk of Nutritional Inadequacy High quality protein is typically consumed via animal products, and therefore vegetarians may consume less high quality protein than omni- vores. Because animal foods are the primary sources of certain nutrients, such as calcium, vitamin B12, and bioavailable iron and zinc, low protein intakes may result in inadequate intakes of these micronutrients. As an example, Janelle and Barr (1995) reported significantly lower intakes of riboflavin, vitamin B12, and calcium by vegans who also consumed lower amounts of protein (10 versus 15 percent of energy) compared with nonvegetarians. Vegetable protein has been shown to decrease plasma cholesterol con- centrations in experimental animals and humans (Nagata et al. When the ratio of casein:soybean protein in the diet was decreased, there was a reduction in total and non-high density lipoprotein cholesterol concentrations (Fernandez et al. In laboratory animals, it was shown that the onset of atherosclerosis was significantly reduced when animals were fed a textured vegetable protein diet compared to a beef protein diet (Kritchevsky et al. The magnitude of this effect for a doubling of the protein intake, in the absence of change in any other nutrient, is a 50 percent increase in urinary calcium (Heaney, 1993). This has two potential detrimental consequences: loss of bone calcium and increased risk of renal calcium stone formation. Loss of calcium from bone is thought to occur because of bone mineral resorption that provides the buffer for the acid produced by the oxidation of the sulfur amino acids of protein (Barzel and Massey, 1998). However, although increased resorption of bone with increased protein intake has been shown (Kerstetter et al. It has recently been concluded that there may be no need to restrain dietary protein intake. Poor protein status itself leads to bone loss, whereas increased protein intake may lead to increased calcium intake, and bone loss does not occur if calcium intake is adequate (Heaney, 1998). In a recent prospective study of men and women aged 55 to 92 years, consumption of animal protein was positively associated with bone mineral density in women, but not in men (Promislow et al. In contrast, Dawson-Hughes and Harris (2002) reported no association between protein intake and bone mineral density in 342 healthy men and women aged 65 years and older. However, when the individuals were given cal- cium citrate malate and vitamin D in addition to the high protein intake, there was a favorable change in bone mineral density. Kidney Stones It has been estimated that 12 percent of the population in the United States will suffer from a kidney stone at some time (Sierakowski et al. The most common form of kidney stone is composed of calcium oxalate, and its formation is promoted by high concentrations of calcium and oxalate in the urine. A high animal protein intake in healthy humans increases urinary calcium and oxalate and the overall probability of form- ing kidney stones by 250 percent (Robertson et al. Conversely, restricting protein intake improved the lithogenic profile in hypercalciuric patients (Giannini et al. Also, the incidence of calcium oxalate stones has been shown to be associated with consumption of animal pro- tein (Curhan et al. In this study, 50 patients were given low animal protein (56 to 64 g/d) and high fiber, plus adequate fluid and calcium, whereas 49 control patients were only instructed to take adequate water and calcium. However, as protein intake was not the only variable, and in view of the data described above suggesting benefits from lower protein intake, further investigation is necessary. Renal Failure Restriction of dietary protein intake is known to lessen the symptoms of chronic renal insufficiency (Walser, 1992). This raises two related, but distinct questions: Do high protein diets have some role in the develop- ment of chronic renal failure? The concept that protein restriction might delay the deterioration of the kidney with age was based on studies in rats in which low energy or low protein diets attenuated the develop- ment of chronic renal failure (Anderson and Brenner, 1986, 1987). In particular, the decline in kidney function in the rat is mostly due to glomerulosclerosis, whereas in humans it is due mostly to a decline in filtration by nonsclerotic nephrons. Also, when creatinine clearance was measured in men at 10- to 18-year intervals, the decline with age did not correlate with dietary protein intake (Tobin and Spector, 1986). Correla- tion of creatinine clearance with protein intake showed a linear relation- ship with a positive gradient (Lew and Bosch, 1991), suggesting that the low protein intake itself decreased renal function. These factors point to the conclusion that the protein content of the diet is not responsible for the progressive decline in kidney function with age. Coronary Artery Disease It is well documented that high dietary protein in rabbits induces hypercholesterolemia and arteriosclerosis (Czarnecki and Kritchevsky, 1993). However, this effect has not been consistently shown in either swine (Luhman and Beitz, 1993; Pfeuffer et al. In humans, analysis of data from the Nurses’ Health Study showed an inverse relation- ship between protein intake and risk of cardiovascular disease (Hu et al. The association was weak but suggests that high protein intake does not increase the risk of cardiovascular disease. Obesity A number of short-term studies indicate that protein intake exerts a more powerful effect on satiety than either carbohydrate or fat (Hill and Blundell, 1990; Rolls et al. However, some epi- demiological studies have shown a positive correlation between protein intake and body fatness, body mass index, and subscapular skinfold (Buemann et al. In contrast, a 6-month randomized trial demonstrated that the replacement of some dietary carbohydrate by protein improved weight loss as part of a reduced fat diet (Skov et al. Cancer The fact that the growth of tumor cells in culture is often increased by high amino acid concentrations (Breillout et al. Reviews of the literature on colon cancer have concluded that high meat intake may be associated with increased risk, but that high total protein intake is not (Clinton, 1993; Giovannucci and Willett, 1994; Parnaud and Corpet, 1997). A lack of cor- relation with total protein intake has been found in a case-control study (Slattery et al. For breast cancer, the geographical distribution of incidence is corre- lated with the availability of dietary protein, especially animal protein (Clinton, 1993). Furthermore, migration to an area with typically higher protein intakes is associated with increased risk of breast cancer (Buell, 1973; Buell and Dunn, 1965). In accord with this, several studies have indicated an association among breast cancer and the intakes of animal protein and fat (Hislop et al. However, others showed a relationship with fat, but not protein intake (Miller et al. More recently, a case-control study on 2,569 patients and 2,588 controls showed a slightly negative relationship between total protein and breast cancer (Decarli et al. For other types of tumors, there also is no clear indication of greater risk with higher protein intakes. Total protein intake was not associated with increased risk of lung cancer (Lei et al. Moreover, in some of these studies, there was an inverse relationship with total protein intake (Barbone et al. On the other hand, higher protein intake was associated with an increased risk of cancer of the upper digestive tract (De Stefani et al. Overall, despite the demonstration of a positive influence of dietary fat and total energy, as well as meat (especially red meat), on some types of tumors, no clear role for total protein has yet emerged. The current state of the literature, therefore, does not permit any recommendation of an upper limit to be made on the basis of cancer risk. Oxidation of low- density lipoproteins: Intraindividual variability and the effect of dietary linoleate supplementation. Fish diet, fish oil and docosahexaenoic acid rich oil lower fasting and postprandial plasma lipid levels. The aging kidney: Structure, function, mecha- nisms, and therapeutic implications. Efficacy of γ- linolenic acid in the treatment of patients with atopic dermatitis. A controlled study on the effects of n-3 fatty acids on lipid and glucose metabolism in non-insulin-dependent diabetic patients. Effect of omega-3 fatty acids on rectal mucosal cell proliferation in subjects at risk for colon cancer. Food and Nutrient Intakes by Individuals in the United States, by Sex and Age, 1994–96. Dietary intake of marine n-3 fatty acids, fish intake, and the risk of coronary disease among men. Dietary fat and risk of coronary heart disease in men: Cohort follow up study in the United States. The role of low-fat diets in body weight control: A meta-analysis of ad libitum dietary intervention studies. Atherogenic lipoprotein phenotype: A proposed genetic marker for coronary heart disease risk. Dietary protein, growth and urea kinetics in severely malnourished chil- dren and during recovery. Improved plasma cholesterol levels in men after a nutrition educa- tion program at the worksite. Decrease in linoleic acid metabolites as a potential mechanism in cancer risk reduction by conjugated linoleic acid. Dietary polyunsaturated fatty acids and cancers of the breast and colorectum: Emerging evidence for their role as risk modifiers. Coronary heart disease in Hawaii: Dietary intake, depot fat, “stress,” smoking, and energy bal- ance in Hawaiian and Japanese men.

cialis sublingual 20 mg cheap

The estimated energy deposition is the average of boys and girls taken from Table 5-15 generic 20mg cialis sublingual with amex. Their estimates were 95 buy cialis sublingual 20 mg, 85 cheap cialis sublingual 20 mg on line, 83, and 83 kcal/kg/d at 3, 6, 9, and 12 months, respectively. Infants receiving human milk for this period would have an energy intake of some 500 kcal/d based on an average volume of milk intake of 0. Children Ages 3 Through 8 Years Evidence Considered in Determining the Estimated Energy Requirement Basal Metabolism. Validation of the Schofield equations has been undertaken by com- paring predicted values with measured values (Torun et al. It is recognized that the energy content of newly synthesized tissues varies in childhood, particularly during the childhood adiposity rebound (Rolland-Cachera, 2001; Rolland-Cachera et al. Growth refers to increases in height and weight and changes in physique, body composition, and organ systems. Maturation refers to the rate and timing of progress toward the mature biological state. Developmental changes occur in the reproductive organs, and lead to the development of secondary gender characteristics and to changes in the cardiorespiratory and muscular systems leading to an increases in strength and endurance. In adolescents, changes in occupational and recreational activities further alter energy requirements. The effect of age on basal metabolism is a function of changes in body composition through adolescence. Physical activity reflects the energy expended in activities beyond basal processes for survival and for the attainment of physical, intellectual, and social well-being. Dietary energy recommendations include recommendations for physical activity compatible with health, pre- vention of obesity, and appropriate social and psychological development. The assessment of habitual physical activity and its impact on the energy needs of adolescents is difficult because of the wide variability in lifestyles. Physical activity is generally viewed as having a favorable influence on the growth and physical fitness of youth, but longitudinal data addressing these relationships are limited. Regular physical activity has no apparent effect on statural growth and biological maturation (i. Data suggesting later menarche in female athletes are associational and retrospective, and do not control for other factors that influence the age at menarche (e. It is also associated with greater skeletal mineralization, bone density, and bone mass (Bailey and McCulloch, 1990). However, excessive training associ- ated with, or causing, sustained weight loss and maintenance of excessively low body weights may contribute to bone loss and increased susceptibility to stress fractures (Dhuper et al. Information is scant on the relationship between children’s physical activity and fitness and present and future health status (Malina, 1994; Twisk, 2001). Most evidence is limited to cross-sectional comparisons of active and nonactive children. Active children tend to have lower skinfold thickness than inactive children (Raitakari et al. Exercise training has been shown to slightly reduce the percentage body fat and improve lipoprotein profile in obese children (Gutin et al. The tracking of body fatness, blood pressure, and lipoprotein profile appears to be moderate from ado- lescence into adulthood (Clarke et al. The energy cost of growth comprises the energy deposited in newly accrued tissues and the energy expended for tissue synthesis. It is recognized that the energy deposited in newly synthesized tissues varies in childhood, particularly around the adolescent growth spurt, but these variations minimally impact total energy requirements. Longitudinal data on the body composition of normally growing adolescents are not avail- able. However, Haschke (1989) estimated the typical body composition of male and female adolescents from literature values of total body water, potassium, and calcium. The energy cost of tissue deposition was approximately 20 kcal/d, increasing to 30 kcal/d at peak growth velocity. Marked variability exists in the energy requirements of adolescents due to varying rates of growth and physical activity levels (Zlotkin, 1996). In adolescents, growth is relatively slow except around the adolescent growth spurt, which varies considerably in timing and magnitude between individuals. Occupational and recreational activities also variably affect energy requirements. The equations below are the same as those used for children ages 3 to 8 years, but the additional amount added to cover energy deposition resulting from growth is somewhat larger (25 kcal/d compared with 20 kcal/d). One way to do this is to evaluate physical efforts by estimating how many miles an individual would have to walk in one day to induce a comparable level of exertion (in terms of kcal expended). Unlike food intake, which is generally underreported, physical activities tend to be overestimated, and activities of one kind may cause a reduction in activities of another. Plots of the residuals showed no evidence of nonlinear patterns of bias (although there was a general increased magnitude of residuals with in- creasing values of each variable). Basal metabolism increases during pregnancy due to the metabolic contribution of the uterus and fetus and increased work of the heart and lungs. The increase in basal metabolism is one of the major components of the increased energy requirements during pregnancy (Hytten, 1991a). In late pregnancy, approximately one-half the increment in energy expenditure can be attributed to the fetus (Hytten, 1991a). The fetus uses about 8 ml O2/kg body weight/min or 56 kcal/kg body weight/d; for a 3-kg fetus, this would be equivalent to 168 kcal/d (Sparks et al. The basal metabolism of pregnant women has been estimated longitu- dinally in a number of studies using a Douglas bag, ventilated hood, or whole-body respiration calorimeter (Durnin et al. Marked variation in the basal metabolic response to pregnancy was seen in 12 British women measured before and through- out pregnancy (Goldberg et al. Energy-sparing or energy-profligate responses to pregnancy were dependent on prepregnancy body fatness. Nonpregnant prediction equations based on weight are not accurate during pregnancy since metabolic rate increases disproportion- ately to the increase in total body weight. In late gestation, the anti-insulinogenic and lipolytic effects of human chorionic somatomammotropin, prolactin, cortisol, and glucagon contrib- ute to glucose intolerance, insulin resistance, decreased hepatic glycogen, and mobilization of adipose tissue (Kalkhoff et al. Although levels of serum prolactin, cortisol, glucagon, and fatty acids were elevated and serum glucose levels were lower in one study, a greater utilization of fatty acids was not observed during late pregnancy (Butte et al. These observations are consistent with persistent glucose production in fasted pregnant women, despite lower fasting plasma glucose concentrations. After fasting, the total rates of glu- cose production and total gluconeogenesis were increased, even though the fraction of glucose oxidized and the fractional contribution of gluco- neogenesis to glucose production remained unchanged (Assel et al. Until late gestation, the gross energy cost of standard- ized nonweight-bearing activity does not significantly change. In the last month of pregnancy, the energy expended while cycling was increased on the order of 10 percent. The energy cost of standardized weight-bearing activities such as treadmill walking was unchanged until 25 weeks of gesta- tion, after which it increased by 19 percent (Prentice et al. Stan- dardized protocols, however, do not allow for behavioral changes in pace and intensity of physical activity, which may occur and conserve energy during pregnancy. Gestational weight gain includes the products of conception (fetus, placenta, and amniotic fluid) and accretion of maternal tissues (uterus, breasts, blood, extracellular fluid, and adipose). The energy cost of deposition can be calculated from the amount of protein and fat deposited. The total energy deposition between 14 and 37+ weeks of gestation was calculated based on an assumed protein deposition of 925 g of protein, and energy equivalences of 5. Total energy deposition during pregnancy was estimated from the mean fat gain of 3. Lactation Evidence Considered in Determining the Estimated Energy Requirement Basal Metabolism. The increased energy expenditure is consistent with the additional energy cost of milk synthesis. Theoretically, the energy cost of lactation could be met by a reduction in the time spent in physical activity or an increase in the efficiency of performing routine tasks. The energetic cost of nonweight-bearing and weight-bearing activities has been measured in lac- tating women (Spaaij et al. Adaptations in the level of physical activity are not always seen in lactating women. Reduc- tions in physical activity have been reported in early lactation (4 to 5 weeks postpartum) in the Netherlands (van Raaij et al. Physical activity increased in the lactating Dutch women from 5 to 27 weeks post- partum (van Raaij et al. While a decrease in moderate and discretionary activities appears to occur in most lactating women in the early postpartum period, activity patterns beyond this period are highly variable. These sources of error may be attributed to isotope exchange and sequestration that occurs during the de novo synthesis of milk fat and lactose, and to increased water flux into milk (Butte et al. Milk energy output is computed from milk pro- duction and the energy density of human milk. Beyond 6 months post- partum, typical milk production rates are variable and depend on weaning practices. The energy density of human milk has been measured by bomb calorimetry or proximate macronutrient analysis of representative 24-hour pooled milk samples. The changes in weight and therefore energy mobilization from tissues occur in some, but not all, lactating women (Butte and Hopkinson, 1998; Butte et al. In general, during the first 6 months postpartum, well-nourished lactating women experience a mild, gradual weight loss, averaging –0. Changes in adipose tissue volume in 15 Swedish women were measured by magnetic resonance imaging (Sohlstrom and Forsum, 1995).

pornplaybb.com siteripdownload.com macromastiavideo.com my site