The danger of weight loss in the elderly

Protein-energy wasting and mortality in chronic kidney disease

Protein-energy wasting (PEW) is common in patients with chronic kidney disease (CKD) and is associated with an increased death risk from cardiovascular diseases. However, while even minor renal dysfunction is an independent predictor of adverse cardiovascular prognosis, PEW becomes clinically manifest at an advanced stage, early before or during the dialytic stage. Mechanisms causing loss of muscle protein and fat are complex and not always associated with anorexia, but are linked to several abnormalities that stimulate protein degradation and/or decrease protein synthesis. In addition, data from experimental CKD indicate that uremia specifically blunts the regenerative potential in skeletal muscle, by acting on muscle stem cells. In this discussion recent findings regarding the mechanisms responsible for malnutrition and the increase in cardiovascular risk in CKD patients are discussed. During the course of CKD, the loss of kidney excretory and metabolic functions proceed together with the activation of pathways of endothelial damage, inflammation, acidosis, alterations in insulin signaling and anorexia which are likely to orchestrate net protein catabolism and the PEW syndrome.

Epigenetic transgenerational actions of endocrine disruptors

Environmental factors have a significant impact on biology. Therefore, environmental toxicants through similar mechanisms can modulate biological systems to influence physiology and promote disease states. The majority of environmental toxicants do not have the capacity to modulate DNA sequence, but can alter the epigenome. In the event an environmental toxicant such as an endocrine disruptor modifies the epigenome of a somatic cell, this may promote disease in the individual exposed, but not be transmitted to the next generation. In the event a toxicant modifies the epigenome of the germ line permanently, then the disease promoted can become transgenerationaly transmitted to subsequent progeny. The current review focuses on the ability of environmental factors such as endocrine disruptors to promote transgenerational phenotypes.

Drug discovery and development for ageing: opportunities and challenges

The prevention and treatment of late-life dysfunction are the goals of most geriatricians and should be the primary target for discovery and development of new medicines for elderly people. However, the development of new medicines for elderly people will face a number of challenges that are not seen for other patient populations. The burdens of multiple chronic diseases, low physiological reserve and polypharmacy must result in new clinical trials in frail older people with a high expectation of safety and efficacy. The etiology of functional limitations in elderly people is complex and often ascribed to conditions that escape the traditional definition of disease. While our society urgently needs new treatments that can reduce the burden of physical decline among older persons, guidelines on how these treatments should be developed and tested are currently lacking, in part because a consensus has not yet been achieved regarding the identifiable target diseases. New potential indications included sarcopaenia, anorexia of ageing, frailty, mobility disability and reduced functional capacity secondary to hospitalization. The challenges to conducting clinical trials in the elderly should not offset the great opportunity for the development of new medicines to prevent or reverse age-associated changes in body composition and poor functional capacity in the elderly.

Challenges and new opportunities for clinical nutrition interventions in the aged

Nutritional status plays a critical role in the prevention and management of many chronic health conditions that are common in the elderly and are likely to become more prevalent as the population ages. This paper highlights several aspects of nutrition that require additional basic science and clinical application research to improve the health and well-being of older adults. Topics addressed are selected demographic and health indices, the uncertain benefits of energy restriction in aged humans compared with other species, the impact of food insecurity on health, the relationship between dietary protein and sarcopenia, the prevention and management of obesity while maintaining muscle mass and functional status, and controversy regarding high intakes of folic acid. Research needs regarding the safety, efficacy, and application of clinical interventions related to these topics also are discussed.

Low-fat dietary pattern and change in body-composition traits in the Women's Health Initiative Dietary Modification Trial

BACKGROUND

The Women's Health Initiative Dietary Modification (DM) Trial was a randomized controlled trial that compared the effects of a low-fat (≤20% of total energy) or a usual diet in relation to chronic disease risk in postmenopausal women.

OBJECTIVE

We characterized long-term body-composition changes associated with the DM trial and potential modifiers of these associations.

DESIGN

In the DM trial, 48,835 women aged 50-79 y were randomly assigned to intervention (40%) or comparison (60%) groups. We studied a subset with whole-body dual-energy X-ray absorptiometry scans at baseline and during follow-up. Changes in fat mass (FM), lean mass (LM), and percentage body fat between the intervention (n = 1580) and comparison (n = 2731) groups at years 1, 3, and 6 were compared. By using generalized estimating equations, we calculated overall differences between groups and tested for interactions with age, diabetes, race-ethnicity (white, black, and Hispanic), body mass index (BMI), and hormone therapy (HT).

RESULTS

The intervention women experienced significantly greater reductions in percentage body fat, FM, and LM at years 1 and 3 than did women in the comparison group (all P < 0.05). At year 6, only the FM change was significantly different between groups. Overall, the intervention was associated with reductions in percentage body fat (-0.8%; 95% CI: -1.0%, -0.6%), FM (-1.1 kg; 95% CI: -1.3, -0.8 kg), and LM (-0.17 kg; 95% CI: -0.28, -0.06 kg) during follow-up (all P < 0.003). Intervention associations varied by race-ethnicity, BMI, diabetes, and HT and remained significant after adjustment for physical activity.

CONCLUSION

This intervention was associated with modest long-term body-composition changes; the findings were more robust in years 1 and 3. This trial was registered at clinicaltrials.gov as NCT00000611.

Body mass index and risk of colorectal cancer in Chinese Singaporeans: the Singapore Chinese Health Study

BACKGROUND

The authors chose to examine the association between body mass index (BMI) and incident colorectal cancer across the spectrum of BMI, including underweight persons, because detailed prospective cohort data on this topic in Asians is scarce, as is data on underweight persons (BMI, <18.5 kg/m(2)) in any population.

METHODS

Analysis of the Singapore Chinese Health Study included 51,251 men and women aged 45-74 years enrolled in 1993-1998 and followed through 2007. Incident cancer cases and deaths among cohort members were identified through record linkage, and 980 cases were identified. Cox regression models were used to investigate the association of baseline BMI with risk of incident colorectal cancer during a mean of 11.5 years of follow-up.

RESULTS

A significant, U-shaped, quadratic association was observed between BMI and colon cancer risk, with increased risk in BMIs ≥27.5 and <18.5 kg/m(2). The association was more pronounced in never smokers and most prominent when further limiting the sample to those free of diabetes and cases with longer than 5 years of follow-up. Localized cases had a more pronounced association in BMIs ≥27.5, whereas advanced cases had a more pronounced association in BMIs <18.5 kg/m(2) . No association was found in relation to rectal cancer risk. The association was also stronger among patients aged 65 years and older.

CONCLUSIONS

BMI displays a U-shaped, quadratic association with colon cancer risk in this Chinese population in Southeast Asia.

Regular multicomponent exercise increases physical fitness and muscle protein anabolism in frail, obese, older adults

Aging is associated with a decline in strength, endurance, balance, and mobility. Obesity worsens the age-related impairment in physical function and often leads to frailty. The American College of Sports Medicine recommends a multicomponent (strength, endurance, flexibility, and balance) exercise program to maintain physical fitness. However, the effect of such an exercise program on physical fitness in frail, obese older adults is not known. We therefore determined the effect of a 3-month long multicomponent exercise training program, on endurance (peak aerobic capacity (VO(2) peak)), muscle strength, muscle mass, and the rate of muscle protein synthesis (basal rate and anabolic response to feeding) in nine 65- to 80-year-old, moderately frail, obese older adults. After 3 months of training, fat mass decreased (P < 0.05) whereas fat-free mass (FFM), appendicular lean body mass, strength, and VO(2) peak increased (all P < 0.05). Regular strength and endurance exercise increased the mixed muscle protein fractional synthesis rate (FSR) but had no effect on the feeding-induced increase in muscle protein FSR (~0.02%/h increase from basal values both before and after exercise training; effect of feeding: P = 0.02; effect of training: P = 0.047; no interaction: P = 0.84). We conclude that: (i) a multicomponent exercise training program has beneficial effects on muscle mass and physical function and should therefore be recommended to frail, obese older adults, and (ii) regular multicomponent exercise increases the basal rate of muscle protein synthesis without affecting the magnitude of the muscle protein anabolic response to feeding.

Effects of chronic fentanyl administration on physical performance of aged rats

There is growing concern over the increasing use of opioids to treat chronic pain in the elderly primarily because of the potential increased sensitivity to the adverse side effects. Here, we use a preclinical model (male Brown Norway X F344 rats aged 12, 18, 24, and 30 months) to describe the outcome of chronic fentanyl administration (1.0mg/kg/day) on various physiological and behavioral measures. Continuous fentanyl administration resulted in an initial decrease in food consumption, followed by the development of tolerance to this effect over a 4-week period and a subsequent increase in food consumption during withdrawal. This change in food consumption was associated with decreases in body weight (predominantly due to a loss of fat mass) that was maintained through early withdrawal. After 1 month of withdrawal, only the 12-month old animals had fully regained body weight. Fentanyl administration resulted in a decrease in grip strength and an increase in locomotor activity that did not differ across age groups. There was no effect of fentanyl administration on rotarod performance. These results demonstrate that while there is a delayed recovery of body mass with age, the observed changes in behavioral responses are uniform across ages.

Inverse association between adiposity and telomere length: The Fels Longitudinal Study

OBJECTIVES

To assess the relationship between telomere length and adiposity, using dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI), in addition to conventional anthropometric proxies including body mass index (BMI) and cardiovascular disease risk factors.

METHODS

A cross-sectional sample of 309 non-Hispanic white participants in the Fels Longitudinal Study aged 8 to 80 yr (52% female) was included. Average telomere length was measured by quantitative PCR.

RESULTS

Telomere length was negatively correlated with age (r = -0.32, P < 0.0001) and had numerous significant correlations with established cardiovascular disease risk factors including waist circumference (r = -0.33), apolipoprotein B (r = -0.26), systolic blood pressure (r = -0.28), and fasting serum glucose (r = -0.15); all P < 0.0025. In backward selection linear regression models of telomere length, adiposity measures were consistently retained in the best models; BMI, waist circumference, hip circumference, total body fat, and visceral adipose tissue volume were all inversely associated with telomere length at the nominal P < 0.05 level or lower, independent of age, sex, systolic blood pressure, and fasting serum lipid, lipoprotein, and glucose concentrations. The negative association of BMI with telomere length was stronger among younger than older participants (P for interaction, 0.03).

CONCLUSIONS

Individuals with higher total and abdominal adiposity have lower telomere length, a marker of cellular senescence, suggesting obesity may hasten the aging process. Longitudinal studies are required to establish the causal association of early life adiposity with biological aging.

Mechanisms of association between obesity and chronic pain in the elderly

Chronic pain is more common in the elderly and impairs functioning and quality of life. Though obesity, defined by body mass index (BMI), has been associated with pain prevalence among older adults, the mechanism of this association remains unclear. We examined components of the metabolic syndrome, insulin resistance, a marker of inflammation, and the presence of painful comorbidities as possible mediators of this association. Participants were 407 individuals aged >70 in the Einstein Aging Study. Chronic pain and pain over the last 3 months were defined using the Total Pain Index (TPI). Insulin resistance was modeled as fasting insulin, HOMA and QUICKI. High sensitivity C-reactive protein was used as a marker of inflammation. Cross-sectional logistic regression models were constructed to assess the associations of these factors with prevalent pain, adjusted for other known pain correlates. Prevalence of chronic pain was 52%. Of the clinical components of metabolic syndrome, central obesity was significantly associated with pain (OR 2.03, 95% CI 1.36-3.01). After adjustment for insulin resistance, inflammation, and pain-related comorbidities, central obesity predicted higher TPI scores (OR 1.55, 95% CI 1.04-2.33) and nearly doubled the risk of chronic pain (OR 1.70, 95% CI 1.05-2.75). Central obesity is the metabolic syndrome component showing the strongest independent association with pain, and the relationship is not explained by markers of insulin resistance or inflammation, nor by the presence of osteoarthritis or neuropathy.

BMI, all-cause and cause-specific mortality in Chinese Singaporean men and women: the Singapore Chinese health study

Background

The optimal range of relative weight for morbidity and mortality in Asian populations is an important question in need of more thorough investigation, especially as obesity rates increase. We aimed to examine the association between body mass index (BMI), all cause and cause-specific mortality to determine the optimal range of BMI in relation to mortality in Chinese men and women in Singapore.

Methodology/Principal Findings

We analyzed data from a prospective cohort study of 51,251 middle-aged or older (45–74) Chinese men and women in the Singapore Chinese Health Study. Participants were enrolled and data on body weight and covariates were collected in 1993–1998 and participants were followed through 2008. The analysis accounted for potential methodological issues through stratification on smoking and age, thorough adjustment of demographic and lifestyle confounders and exclusion of deaths early in the follow-up.

Conclusions/Significance

Increased risk of mortality was apparent in underweight (<18.5) and obese BMI categories (≥27.5) independent of age and smoking. Regardless of age or BMI, smoking considerably increased the rate of mortality and modified the association between BMI and mortality. The most favorable range of BMI for mortality rates and risk in non-smoking persons below age 65 was 18.5–21.4 kg/m², and for non-smoking persons aged 65 and above was 21.5–24.4 kg/m².

Perceived weight status, overweight diagnosis, and weight control among US adults: the NHANES 2003-2008 Study

OBJECTIVES

To examine the association between perceived overweight status and weight control, discrepancies between perceived and measured weight status, and opportunities for health care professionals (HCPs) to correct weight perception among US adults.

DESIGN

Population-based cross-sectional study.

SUBJECTS

In all, 16,720 non-pregnant adults from the 2003 to 2008 National Health and Nutrition Examination Survey.

RESULTS

Overall, 64% (73% women, 55% men) reported a desire to weigh less and 48% (57% women, 40% men) reported pursuing weight control. Weight control was positively associated with overweight perception (odds ratio (OR) women 3.74; 95% confidence interval (CI) 2.96, 4.73; OR men 2.82; 95% CI 2.11, 3.76) and an HCP diagnosis of overweight/obesity (OR women 2.22; 95% CI 1.69, 2.91; OR men 2.14; 95% CI 1.58, 2.91), independent of measured weight status. A large proportion of overweight individuals (23% women, 48% men) perceived themselves as having the right weight. Also, 74% of overweight and 29% of obese individuals never had an HCP diagnosis of overweight/obesity. Although the majority of overweight/obese individuals (74% women, 60% men) pursued at least one weight management strategy, fewer (39% women, 32% men) pursued both dietary change and physical activity. Among overweight/obese adults, those with an HCP diagnosis of overweight/obesity were more likely to diet (74 versus 52%), exercise (44 versus 34%), or pursue both (41 versus 30%, all P<0.01) than those who remained undiagnosed.

CONCLUSION

HCPs have unused opportunities to motivate their patients to control and possibly lose weight by correcting weight perceptions and offering counseling on healthy weight loss strategies.

Adaptive senectitude: the prolongevity effects of aging

In the past, it has been assumed that all the biological and medical changes that occur in old age are deleterious. It has therefore been concluded that treatment and prevention of such changes in old age should increase healthspan and delay death. However, accruing epidemiological and clinical trial evidence in older humans suggests that this is not the case. Some studies have shown that antioxidants and hormone supplements increase mortality, whereas high blood pressure, obesity, and metabolic syndrome are often associated with improved outcomes in very elderly people. Perhaps, some of these supposedly detrimental changes accompanying old age are in fact evolutionary adaptations to prolong life after reproduction in humans. Indeed, a form of reverse antagonistic pleiotropy or adaptive senectitude might be occurring. Some common biological and medical changes in old age might actually enhance longevity and represent novel targets for improving health in older people.

Position of the American Dietetic Association: individualized nutrition approaches for older adults in health care communities

It is the position of the American Dietetic Association that the quality of life and nutritional status of older adults residing in health care communities can be enhanced by individualization to less-restrictive diets. The American Dietetic Association advocates for registered dietitians to assess and evaluate the need for nutrition interventions tailored to each person's medical condition, needs, desires, and rights. Dietetic technicians, registered, assist registered dietitians in the assessment and implementation of individualized nutrition care. Health care practitioners must assess risks vs benefits of therapeutic diets, especially for older adults. Food is an essential component of quality of life; an unpalatable or unacceptable diet can lead to poor food and fluid intake, resulting in undernutrition and related negative health effects. Including older individuals in decisions about food can increase the desire to eat and improve quality of life. The Practice Paper of the American Dietetic Association: Individualized Nutrition Approaches for Older Adults in Health Care Communities provides guidance to practitioners on implementation of individualized diets and nutrition care.

Determinants of serum-induced SIRT1 expression in older men: the CHAMP study

Circulating factors that have an effect on SIRT1 expression are influenced by caloric restriction. To determine the association between frailty and such circulating factors, we measured serum-induced SIRT1 expression from a nested cohort of frail (n = 77) and robust (n = 82) participants from Concord Health and Ageing in Men Project, a population-based study of community-dwelling men older than 70 years. Serum-induced SIRT1 expression was not different between frail and robust men (103.1 ± 17.0 versus 100.4 ± 19.3 μg/L). However, subsequent analyses showed that men with the lowest values (first quartile) were less likely to be frail (odds ratio = 0.5, 95% confidence interval = 0.2-1.0, p = .04) and had higher total body lean mass (p = .001) than the other participants. Serum-induced SIRT1 expression did not correlate with age, diseases, medications, albumin, fasting glucose, or lipids. Overall, there was no association between frailty and serum-induced SIRT1 expression; however, post hoc analysis suggested that there might be a paradoxical association between low serum-induced SIRT1 expression and robustness.

Effect of intermittent fasting on prostate cancer tumor growth in a mouse model

Caloric restriction (CR) has been shown to have anti-cancer properties. However, CR may be difficult to apply in humans secondary to compliance and potentially deleterious effects. An alternative is intermittent CR, or in the extreme case intermittent fasting (IF). In a previous small pilot study, we found 2 days per week of IF with ad libitum feeding on the other days resulted in trends toward prolonged survival of mice bearing prostate cancer xenografts. We sought to confirm these findings in a larger study. A total of 100 (7- to 8-week-old) male severe combined immunodeficiency mice were injected subcutaneously with 1 × 10(5) LAPC-4 prostate cancer cells. Mice were randomized to either ad libitum Western Diet (44% carbohydrates, 40% fat and 16% protein) or ad libitum Western Diet with twice-weekly 24 h fasts (IF). Tumor volumes and mouse bodyweights were measured twice weekly. Mice were killed when tumor volumes reached 1000 mm(3). Serum and tumor were collected for analysis of the insulin/insulin-like growth factor 1 (IGF-1) hormonal axis. Overall, there was no difference in mouse survival (P=0.37) or tumor volumes (P ≥ 0.10) between groups. Mouse body weights were similar between arms (P=0.84). IF mice had significantly higher serum IGF-1 levels and IGF-1/IGFBP-3 ratios at killing (P<0.001). However, no difference was observed in serum insulin, IGFBP-3 or tumor phospho-Akt levels (P ≥ 0.39). IF did not improve mouse survival nor did it delay prostate tumor growth. This may be secondary to metabolic adaptations to the 24 h fasting periods. Future studies are required to optimize CR for application in humans.

Clinical practice in nursing homes as a key for progress

With the aging of the world's population there has become a major need for the development of nursing homes throughout the world. While some countries provide high quality care for the disabled elderly, in others this is not the case. Education of a medical director has been shown to improve the quality of the nursing home. Physicians need to have knowledge of how to implement continuous quality improvement and culture change. Key medical issues include moving to a restraint free environment, subsyndromal delirium, behavioral disturbances, weight loss, pain management, pressure ulcers, falls, hip fractures, polypharmacy, depression and frailty.

Obesity in older adults: relationship to functional limitation

PURPOSE OF REVIEW

The present review is intended to provide a critical overview of recent investigations of obesity among older persons with emphasis upon associated functional limitations, potential for intervention, and a future research agenda.

RECENT FINDINGS

Obesity is growing in prevalence among older persons. The association between obesity and functional decline is well documented. Recent findings suggest possible contributions of obesity-associated inflammatory milieu, sarcopenia, and impairment of muscle function/strength to adverse functional outcomes. A growing body of literature supports consideration of moderate weight reduction to secure improved metabolic and functional parameters for obese older persons.

SUMMARY

Obesity is associated with an unfortunate burden of chronic disease, functional limitation, and poor life quality. In view of the growing numbers of afflicted older individuals, there must be research priority to discern how obesity impacts function so that appropriate prevention and treatment strategies may be adopted.

Masticatory dysfunction is associated with worse functional ability: a population-based study

AIM

Because of the ageing of populations, disability has become an emergent problem from the clinical, social, and economic perspectives. Nevertheless, the determinants of disability in older subjects are still unclear. We assessed the association between self-assessed masticatory dysfunction (MD) and functional ability in older subjects.

MATERIALS AND METHODS

We analysed data of all 350 subjects aged 75+ living in Tuscania (Italy). Functional ability was estimated using the Katz' activities of daily living (ADLs), and the Lawton and Brody instrumental activities of daily living (IADLs) scales.

RESULTS

MD was reported by 145 (41%) participants. Disability in the ADLs and IADLs was found in 37 (25%) and 53 (37%) of participants with MD, respectively, but only in 11 (5%) and 30 (15%) of the other participants (p<0.001). MD was associated with disability in the ADLs [odds ratio (OR)=2.40, 95% confidence interval (CI)=1.05-5.51], and IADLs (OR=2.77, 95% CI=1.07-7.16) in logistic regression, after adjusting. The association of MD with disability was stronger among subjects aged 80+.

CONCLUSIONS

MD is independently associated with disability in community-dwelling elderly. Further studies are needed to evaluate the impact of early detection and correction of MD on the preservation of functional status in older populations.

Normal body mass index rather than obesity predicts greater mortality in elderly people: the Jerusalem longitudinal study

OBJECTIVES

To examine the association between body mass index (BMI) and mortality in older people.

DESIGN

A longitudinal cohort study of an age-homogenous, representative sample born in 1920/21.

SETTING

Community-based home assessments.

PARTICIPANTS

West Jerusalem residents born in 1920/21 examined at baseline in 1990 (n=447), with additional recruitment waves in 1998 (n=870) and 2005 (n=1,086).

MEASUREMENTS

Comprehensive assessment of health variables including BMI (m/kg(2)) at ages 70, 78, and 85. The primary outcome of mortality was collected from age 70 to 88 (1990-2008). Adjusted Cox proportional hazards analysis was used to calculate hazard ratios (HRs) for mortality according to unit increase in BMI.

RESULTS

A unit increase in BMI in women resulted in HRs of 0.94, (95% confidence interval (CI)=0.89-0.99) at age 70, 0.95 (95% CI=0.91-0.98) at age 78, and 0.91 (95% CI=0.86-0.98) at age 85. Similarly, in men, HRs were 0.99 (95% CI=0.95-1.05) at age 70, 0.94 (95% CI=0.91-0.98) at age 78, and 0.91 (95% CI=0.86-0.98) at age 85. A time-dependent analysis of 450 subjects followed for 18 years confirmed the above findings; a unit increase in BMI resulted in HRs of 0.93 (95% CI=0.87-0.99) in women and 0.93(95% CI=0.88-0.98) in men. Eliminating the first third of follow-up mortality to account for possibility of reverse causality did not change the results.

CONCLUSION

Higher BMI was associated with lower mortality from age 70 to 88.

Dynapenic-obesity and physical function in older adults

BACKGROUND

Dynapenia (low muscle strength) and obesity are associated with an impaired physical function. It was hypothesized that older individuals with both conditions (dynapenic-obesity) would have a more impaired physical function than individuals with dynapenia or obesity alone.

METHODS

This cross-sectional study included 2,039 men and women aged 55 years and older from the 1999-2002 National Health and Nutrition Examination Survey. Fat mass was measured by dual-energy x-ray absorptiometry and leg strength by dynamometer. Based on fat mass and leg strength tertiles, four independent groups were identified: non-dynapenic and non-obese, obese alone, dynapenic alone, and dynapenic-obese. An objective physical function measure was obtained from a 20-foot walking speed test, whereas subjective physical function measures were obtained from five self-reported questions.

RESULTS

Within both sexes, the dynapenic-obese group had a slower walking speed than the non-dynapenic and non-obese and obese-alone groups (p <or= .01) but not the dynapenic-alone group. Similarly, with the exception of the dynapenic-alone group in men, the global subjective score was lower in the dynapenic-obese group than in the non-dynapenic and non-obese and obese-alone groups (p <or= .01). By comparison to the dynapenic-obese group, the adjusted odds ratios (95% confidence interval) for walking disability were 0.21 (0.12-0.35) in the non-dynapenic and non-obese, 0.34 (0.20-0.56) in the obese-alone, and 0.54 (0.33-0.89) in the dynapenic-obese groups. The corresponding odds ratios for a disability based on the global subjective score were 0.20 (0.09-0.42), 0.60 (0.30-1.21), and 0.41 (0.19-0.87).

CONCLUSION

Dynapenic-obesity was associated with a poorer physical function than obesity alone and in most cases with dynapenia alone.

Cellular mechanisms of cardioprotection by calorie restriction: state of the science and future perspectives

Evidence from animal models and preliminary studies in humans indicates that calorie restriction (CR) delays cardiac aging and can prevent cardiovascular disease. These effects are mediated by a wide spectrum of biochemical and cellular adaptations, including redox homeostasis, mitochondrial function, inflammation, apoptosis, and autophagy. Despite the beneficial effects of CR, its large-scale implementation is challenged by applicability issues as well as health concerns. However, preclinical studies indicate that specific compounds, such as resveratrol, may mimic many of the effects of CR, thus potentially obviating the need for drastic food intake reductions. Results from ongoing clinical trials will reveal whether the intriguing alternative of CR mimetics represents a safe and effective strategy to promote cardiovascular health and delay cardiac aging in humans.

Resistance training preserves fat-free mass without impacting changes in protein metabolism after weight loss in older women

This study assessed the effects of resistance training (RT) on energy restriction-induced changes in body composition, protein metabolism, and the fractional synthesis rate of mixed muscle proteins (FSRm) in postmenopausal, overweight women. Sixteen women (age 68 +/- 1 years, BMI 29 +/- 1 kg/m(2), mean +/- s.e.m.) completed a 16-week controlled diet study. Each woman consumed 1.0 g protein/kg/day. At baseline (weeks B1-B3) and poststudy (weeks RT12-RT13), energy intake matched each subject's need and during weeks RT1-RT11 was hypoenergetic by 2,092 kJ/day (500 kcal/day). From weeks RT1 to RT13, eight women performed RT 3 day/week (RT group) and eight women remained sedentary (SED group). RT did not influence the energy restriction-induced decrease in body mass (SED -5.8 +/- 0.6 kg; RT -5.0 +/- 0.2 kg) and fat mass (SED -4.1 +/- 0.9 kg; RT -4.7 +/- 0.5 kg). Fat free mass (FFM) and total body water decreased in SED (-1.6 +/- 0.4 and -2.1 +/- 0.5 kg) and were unchanged in RT (-0.3 +/- 0.4 and -0.4 +/- 0.7 kg) (group-by-time, P < or = 0.05 and P = 0.07, respectively). Protein-mineral mass did not change in either group (SED 0.4 +/- 0.2 kg; RT 0.1 +/- 0.4 kg). Nitrogen balance, positive at baseline (2.2 +/- 0.3 g N/day), was unchanged poststudy. After body mass loss, postabsorptive (PA) and postprandial (PP) leucine turnover, synthesis, and breakdown decreased. Leucine oxidation and balance were not changed. PA and total (PA + PP) FSRm in the vastus lateralis were higher after weight loss. RT did not influence these protein metabolism responses. In summary, RT helps older women preserve FFM during body mass loss. The comparable whole-body nitrogen retentions, leucine kinetics, and FSRm between groups are consistent with the lack of differential protein-mineral mass change.