The effect of middle- and old-age body mass index on short-term mortality in older people

Trends in underweight and severe underweight disparities in Korean adults and older adults: a nationwide, repeated cross-sectional study

OBJECTIVES

Little is known about the disparities in underweight prevalence among the general population in high-income countries. We investigated the trends in underweight prevalence and disparities across sociodemographic groups among Korean adults and older adults.

SETTING AND PARTICIPANTS

A series of cross-sectional data on Korean national health checkups for adults aged ≥20 years were analyzed from 2005 to 2016.

MEASUREMENTS

Based on body mass index (kg/m2), underweight was graded as mild (17.0-18.49), moderate (16.0-16.9), and severe (<16.0). Underweight prevalence was compared across sociodemographic subgroups in 2015-2016. Trends in underweight disparities were examined from 2005-2006 to 2015-2016. Multivariable-adjusted odds ratios (ORs; 95% confidence intervals, CIs) were calculated using logistic regression.

RESULTS

Approximately 11-22 million adults were included in each wave. In 2015-2016, the overall prevalence of underweight was 3.6% (men 2.0%, women 5.2%); severe underweight was 0.2% (men 0.1%, women 0.3%). The prevalence of underweight varied by sex and age groups. In men, those aged ≥80 years had the highest prevalence (overall 7.33%, severe underweight 0.84%). In women, those aged 20-29 years had the highest prevalence of overall underweight (14.57%), whereas those aged ≥80 years had the highest prevalence of severe underweight (1.38%). Compared with individuals in the lowest income quartile, men in the highest income had lower ORs of overall (0.59, 95% CI 0.59-0.60) and severe underweight (0.46, 95% CI 0.44-0.48); women in the highest income quartile had a higher OR of overall (1.12, 95% CI 1.12-1.13) but a lower OR of severe underweight (0.89, 95% CI 0.86-0.92). From 2005-2006 to 2015-2016, severe underweight consistently declined in older men but remained constant in women aged ≥80 years, widening sex disparities among older adults. Severe underweight decreased or leveled off in the highest income quartile but steadily increased in the lowest quartile, worsening income disparities.

CONCLUSION

In this nationwide study, underweight was more prevalent among women, older adults aged ≥80 years, and low-income individuals. Disparities in severe underweight widened across sociodemographic subgroups over time.

Relationship between nutritional status and clinical outcomes among older individuals using long-term care services: A systematic review and meta-analysis

BACKGROUND & AIMS

Nutritional status is a significant issue in an aging society; however, the impact of the nutritional status of older individuals using long-term care services on the caregiving burden remains unclear. This systematic review and meta-analysis aimed to investigate the impact of nutritional issues on adverse outcomes in older individuals using long-term care services.

METHODS

We used data from the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, Web of Science, CINAHL, and Ichu-shi Web databases. Original articles published in English or Japanese between January 2000 and July 2022 were included. The inclusion criteria were interventional and observational studies on individuals using long-term care services with aged ≥65 years and a focus on body weight or weight loss. Data on adverse outcomes related to caregiving burden, including the number of people requiring care, mortality, complications, activities of daily living (ADL), and quality of life, were collected.

RESULTS

The literature search yielded 7873 studies, of which 35 were ultimately included. Seven observational studies investigated mortality outcomes, and seven examined ADL outcomes. The meta-analysis revealed significantly higher mortality rates in individuals classified as underweight (BMI <18.5 kg/m2) than in those with BMI ≥18.5 kg/m2 (risk ratio [RR] 1.49; 95 % confidence interval [CI] 1.31 to 1.73, 0.22; I2 93 %). Further, on categorising the participants based on a BMI cutoff of 25 kg/m2, those with a BMI of <25 kg/m2 had a significantly increased mortality rate (RR 1.21; 95 % CI 1.04-1.40; I2 = 98 %). BMI and weight loss did not affect ADL.

CONCLUSIONS

Our findings indicate that underweight and weight loss are significantly associated with increased mortality in older individuals using long-term care services. Therefore, appropriate weight management is recommended for this population. However, further research is necessary owing to the high heterogeneity observed in this study.

Accuracy of body mass index measurements in community-dwelling older Japanese people based on self-reported anthropometric data

PURPOSE

The aim was to assess the accuracy of body mass index (BMI) measurements in Japanese older people based on self-reported anthropometric data.

METHODS

The study participants were 420 older people aged 65 years or older who were living independently in their communities. The participants' BMIs were calculated based on height and weight values obtained from self-reported questionnaires and actual measurements. The concordance between self-reported and measured BMI values was then analyzed using intraclass correlation coefficients (ICCs) and 95% limits of agreement (95% LOA) stratified by sex.

RESULTS

The ICCs were 0.964 in men and 0.970 in women; however, the 95% LOA were relatively broad, ranging from - 1.07 to 1.39 kg/m² in men and from - 1.52 to 1.46 kg/m² in women.

CONCLUSIONS

These findings suggest that BMI assessments in Japanese older people should be based on measured as opposed to self-reported values when investigating changes in BMI over time.

Changes in Body Mass Index and Late Postoperative Outcomes in Elderly Coronary Artery Bypass Grafting Patients: A Follow-up Study

The purpose of this study was to describe the extent to which late postoperative health outcomes vary as a function of change in body mass index (BMI) in persons 65 years of age undergoing elective coronary artery bypass grafting (CABG). The mean age of the 90 persons in the original sample was 72.27 (±4.85) years. At follow-up (x = 18.73,s = 2.56 months postsurgery), 90% (n = 79 alive,n = 2 deceased, proxy completed interview) were contacted; 73% (n = 59) completed the telephone interview; and 9% (n = 8) were alive but lost to follow-up. BMI (kg/m2) was calculated from self-reported weight at follow-up. Outcomes included the Physical Component Summary (PCS) scale of the SF-36 Health Survey and readmission data. Thex (s ) for BMI at preoperative, postoperative, postdischarge, and follow-up were 28.1 (4.9) kg/ m2 , 28.76 (4.9) kg/m2, 27.11 (4.8) kg/m2, and 27.95 (4.7) kg/m2, respectively. BMI changed over time,P < 0.05. Those who were readmitted lost more weight between preoperative and postdischarge than those who were not readmitted (x BMI = –2.26 vs.x BMI = –1.35),t = 2.17,df = 27.05,P = 0.04. Those who lost less weight between preoperative and postdischarge were less likely to be readmitted,.2 = 5.755 (1),P = 0.02, with 25% sensitivity and 92% specificity. Thex (sx) for PCS at preoperative, postdischarge, and follow-up were 36.93 (1.62), 35.72 (1.27), and 42.26 (1.45), respectively, reflecting change over time,F = 11.43 (2),P < 0.001. At follow-up, older elective CABG patients do not appear to regain weight lost between preoperative and postdischarge; however, self-reported physical health is improved. Also, initial weight loss is related to readmissions.

Inverse relationship between body mass index and mortality in older nursing home residents: a meta-analysis of 19,538 elderly subjects

Body mass index (BMI) and mortality in old adults from the general population have been related in a U-shaped or J-shaped curve. However, limited information is available for elderly nursing home populations, particularly about specific cause of death. A systematic PubMed/EMBASE/CINAHL/SCOPUS search until 31 May 2014 without language restrictions was conducted. As no published study reported mortality in standard BMI groups (<18.5, 18.5-24.9, 25-29.9, ≥30 kg/m(2)), the most adjusted hazard ratios (HRs) according to a pre-defined list of covariates were obtained from authors and pooled by random-effect model across each BMI category. Out of 342 hits, 20 studies including 19,538 older nursing home residents with 5,223 deaths during a median of 2 years of follow-up were meta-analysed. Compared with normal weight, all-cause mortality HRs were 1.41 (95% CI = 1.26-1.58) for underweight, 0.85 (95% CI = 0.73-0.99) for overweight and 0.74 (95% CI = 0.57-0.96) for obesity. Underweight was a risk factor for higher mortality caused by infections (HR = 1.65 [95% CI = 1.13-2.40]). RR results corroborated primary HR results, with additionally lower infection-related mortality in overweight and obese than in normal-weight individuals. Like in the general population, underweight is a risk factor for mortality in old nursing home residents. However, uniquely, not only overweight but also obesity is protective, which has relevant nutritional goal implications in this population/setting.

Association of age and BMI with kidney function and mortality: a cohort study

BACKGROUND

Compared with normal weight, obesity might be associated with worse clinical outcomes, including chronic kidney disease. Whether this association is modified by age is not known. We investigated the association of BMI with progressive loss of kidney function and all-cause mortality in US veterans.

METHODS

In a national cohort of 3,376,187 US veterans with an estimated glomerular filtration rate (eGFR) of more than 60 mL/min per 1·73 m(2), we assessed the association of BMI in patients of different ages (<40 years, 40 years to <50 years, 50 years to <60 years, 60 years to <70 years, 70 years to <80 years, and ≥80 years) with loss of kidney function and with all-cause mortality in logistic regression models and Cox proportional hazards models adjusted for ethnic origin, sex, comorbidities, medications, and baseline eGFR.

FINDINGS

274,764 (8·1%) of 3,376,187 veterans had a rapid decline in kidney function (decrease in slope of >5 mL/min per 1·73 m(2)). The lowest risk for loss of kidney function was noted in patients with BMI of at least 25 kg/m(2) but less than 30 kg/m(2). A generally consistent U-shaped association was noted between BMI and rapid loss of kidney function that was more prominent with increasing age, except in the patients younger than 40 years, in whom BMI did not seem to be predictive of renal function impairment. 672,341 veterans died (28·7 per 1000 patient-years, 95% CI 28·6-28·7) over a median follow-up of 6·8 years (IQR 6·5-7·7). BMI also showed a U-shaped association with mortality, which was similar in all age groups.

INTERPRETATION

A BMI of 30 kg/m(2) or more is associated with rapid loss of kidney function in patients with eGFR of at least 60 mL/min per 1·73 m(2), and this association is accentuated in older patients. A BMI of 35 kg/m(2) or more is also associated with high mortality. A BMI of at least 25 kg/m(2) but less than 30 kg/m(2) is associated with the best clinical outcomes.

FUNDING

National Institute of Health, Memphis VA Medical Center, Long Beach VA Healthcare System, Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Health Services Research and Development, and VA Information Resource Center.

Effect of weight loss on mortality in overweight and obese nursing home residents during a 5-year follow-up

BACKGROUND/OBJECTIVES

The objective of this study was to ascertain the effect of weight loss over the course of 1 year on 5-year mortality in old nursing home (NH) residents in different classes of body mass index (BMI).

SUBJECTS/METHODS

A longitudinal study was conducted on 161 NH residents aged ⩾ 70 years at the Istituto di Riposo per Anziani, Padova, Italy. Data were collected using a comprehensive geriatric assessment at baseline and at a 1-year follow-up visit. Mortality was recorded over a 5-year follow-up. We divided our sample into four groups using as cutoffs a BMI of 25 and a weight gain or loss of 5% at 1 year (BMI ⩾ 25 and weight stable/gain, BMI ⩾ 25 and weight loss, BMI<25 and weight stable/gain and BMI <25 and weight loss).

RESULTS

People with a BMI ⩾ 25 and weight loss suffered the worst decline in activities of daily living, whereas those with a BMI <25 and weight loss had the most significant decline in nutritional status, which coincided with the worst decline in the Multidimensional Prognostic Index among the groups whose weight changed. Compared with those with a BMI ⩾ 25 and weight stable/gain (reference group), those with a BMI <25 were at the highest risk of dying (in association with weight loss: hazard ratio HR=3.60, P=0.005; in association with weight stable/gain: HR=2.45, P=0.01), and the mortality risk was also increased in people with a BMI ⩾ 25 and weight loss (HR=1.74, P=0.03).

CONCLUSIONS

In conclusion, weight loss increases the mortality risk in frail, disabled NH residents, even if they are overweight or obese.

Diet quality and body mass index are associated with health care resource use in rural older adults

Health care resource consumption is a growing concern. The aim of this study was to examine the associations between diet quality and body mass index with health care resource use (HRU) in a cohort of advanced age. Participants in the Geisinger Rural Aging Study (n=5,993) were mailed demographic and dietary questionnaires in 2009. Of those eligible, 2,995 (50%; 1,267 male, 1,728 female; mean age 81.4±4.4 years) provided completed surveys. Multivariate negative binomial models were used to estimate relative risk and 95% CI of HRU outcomes with diet quality as assessed by the Dietary Screening Tool score and body mass index determined from self-reported height and weight. Poor diet quality was associated with a 20% increased risk for emergency room (ER) visits. Fruit and vegetable consumption was grouped into quintiles of intake, with the highest quintile serving as the reference group in analyses. The three lowest fruit and vegetable quintiles were associated with increased risk for ER visits (23% to 31%); the lowest quintile increased risk for inpatient visits (27%). Obesity increased risk of outpatient visits; however, individuals with class I obesity were less likely than normal-weight individuals to have ER visits (relative risk=0.84; 95% CI 0.70 to 0.99). Diets of greater quality, particularly with greater fruit and vegetable intake, are associated with favorable effects on HRU outcomes among older adults. Overweight and obesity are associated with increased outpatient HRU and, among obese individuals, with decreased ER visits. These findings suggest that BMI and diet quality beyond age 74 years continue to affect HRU measures.

J-shapedness: an often missed, often miscalculated relation: the example of weight and mortality

We present three considerations in analysing the association between weight and mortality, as well as other relations that might be non-linear in nature. First, authors must graphically plot their independent and dependent variables in a continuous manner. Second, authors should assess the shape of that relation, and note its shape. If it is non-linear, and specifically, J-shaped or U-shaped, careful consideration should be given to using the 'best' statistical model, of which multivariate fractional polynomial regression is a reasonable choice. Authors should also refrain from truncating their data to avoid dealing with non-linear relations.

Association of body mass index with outcomes in patients with CKD

Obesity is associated with higher mortality in the general population, but this association is reversed in patients on dialysis. The nature of the relationship of obesity with adverse clinical outcomes in nondialysis-dependent CKD and the putative interaction of the severity of disease with this association are unclear. We analyzed data from a nationally representative cohort of 453,946 United States veterans with eGFR<60 ml/min per 1.73 m(2). The associations of body mass index categories (<20, 20 to <25, 25 to <30, 30 to <35, 35 to <40, 40 to <45, 45 to <50, and ≥50 kg/m(2)) with all-cause mortality and disease progression (using multiple definitions, including incidence of ESRD, doubling of serum creatinine, and the slopes of eGFR) were examined in Cox proportional hazards models and logistic regression models. Multivariable adjustments were made for age, race, comorbidities and medications, and baseline eGFR. Body mass index showed a relatively consistent U-shaped association with clinical outcomes, with the best outcomes observed in overweight and mildly obese patients. Body mass index levels <25 kg/m(2) were associated with worse outcomes in all patients, independent of severity of CKD. Body mass index levels ≥35 kg/m(2) were associated with worse outcomes in patients with earlier stages of CKD, but this association was attenuated in those patients with eGFR<30 ml/min per 1.73 m(2). Thus, until clinical trials establish the ideal body mass index, a cautious approach to weight management is warranted in this patient population.

Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis

IMPORTANCE

Estimates of the relative mortality risks associated with normal weight, overweight, and obesity may help to inform decision making in the clinical setting.

OBJECTIVE

To perform a systematic review of reported hazard ratios (HRs) of all-cause mortality for overweight and obesity relative to normal weight in the general population.

DATA SOURCES

PubMed and EMBASE electronic databases were searched through September 30, 2012, without language restrictions.

STUDY SELECTION

Articles that reported HRs for all-cause mortality using standard body mass index (BMI) categories from prospective studies of general populations of adults were selected by consensus among multiple reviewers. Studies were excluded that used nonstandard categories or that were limited to adolescents or to those with specific medical conditions or to those undergoing specific procedures. PubMed searches yielded 7034 articles, of which 141 (2.0%) were eligible. An EMBASE search yielded 2 additional articles. After eliminating overlap, 97 studies were retained for analysis, providing a combined sample size of more than 2.88 million individuals and more than 270,000 deaths.

DATA EXTRACTION

Data were extracted by 1 reviewer and then reviewed by 3 independent reviewers. We selected the most complex model available for the full sample and used a variety of sensitivity analyses to address issues of possible overadjustment (adjusted for factors in causal pathway) or underadjustment (not adjusted for at least age, sex, and smoking).

RESULTS

Random-effects summary all-cause mortality HRs for overweight (BMI of 25-<30), obesity (BMI of ≥30), grade 1 obesity (BMI of 30-<35), and grades 2 and 3 obesity (BMI of ≥35) were calculated relative to normal weight (BMI of 18.5-<25). The summary HRs were 0.94 (95% CI, 0.91-0.96) for overweight, 1.18 (95% CI, 1.12-1.25) for obesity (all grades combined), 0.95 (95% CI, 0.88-1.01) for grade 1 obesity, and 1.29 (95% CI, 1.18-1.41) for grades 2 and 3 obesity. These findings persisted when limited to studies with measured weight and height that were considered to be adequately adjusted. The HRs tended to be higher when weight and height were self-reported rather than measured.

CONCLUSIONS AND RELEVANCE

Relative to normal weight, both obesity (all grades) and grades 2 and 3 obesity were associated with significantly higher all-cause mortality. Grade 1 obesity overall was not associated with higher mortality, and overweight was associated with significantly lower all-cause mortality. The use of predefined standard BMI groupings can facilitate between-study comparisons.

Lifestyle risk factors predict disability and death in healthy aging adults

BACKGROUND

Associations between modifiable health risk factors during middle age with disability and mortality in later life are critical to maximizing longevity while preserving function. Positive health effects of maintenance of normal weight, routine exercise, and nonsmoking are known for the short and intermediate term. We studied the effects of these risk factors into advanced age.

METHODS

A cohort of 2327 college alumnae aged 60 years or more was followed annually (1986-2005) by questionnaires addressing health risk factors, history, and Health Assessment Questionnaire disability. Mortality data were ascertained from the National Death Index. Low-, medium-, and high-risk groups were created on the basis of the number (0, 1, ≥2) of health risk factors (overweight, smoking, inactivity) at baseline. Disability and mortality for each group were estimated from unadjusted data and regression analyses. Multivariable survival analyses estimated time to disability or death.

RESULTS

The medium- and high-risk groups had higher disability than the low-risk group throughout the study (P<.001). Low-risk subjects had onset of moderate disability delayed 8.3 years compared with high-risk subjects. Mortality rates were higher in the high-risk group (384 vs 247 per 10,000 person-years). Multivariable survival analyses showed the number of risk factors to be associated with cumulative disability and increased mortality.

CONCLUSION

Seniors with fewer behavioral risk factors during middle age have lower disability and improved survival. These data document that the associations of lifestyle risk factors on health continue into the ninth decade.

The Relationship between Heart Rate Variability and Adiposity Differs for Central and Overall Adiposity

While frank obesity is associated with reduced HRV, indicative of poorer autonomic nervous system (ANS) function, the association between body mass index (BMI) and HRV is less clear. We hypothesized that effects of adiposity on ANS are mostly mediated by visceral fat and less by subcutaneous fat; therefore, centrally distributed adipose tissue, that is, waist circumference (WC), should be more strongly associated with HRV than overall adiposity (BMI). To examine this hypothesis, we used data collected in a subset of the Baltimore Longitudinal Study of Aging to compare strength of association between HRV and WC to that of HRV and BMI. Time domain HRV variables SDNN (standard deviation of successive differences in normal-to-normal (N-N) intervals) and RMSSD (root mean square of successive differences in N-N intervals) were calculated from 24-hour Holter recordings in 159 participants (29-96 years). Increasing WC was associated with decreasing SDNN and RMSSD in younger but not older participants (P value for WC-by-age interaction = 0.003). BMI was not associated with either SDNN or RMSSD at any age. In conclusion, central adiposity may contribute to sympathetic and parasympathetic ANS declines early in life.

A systematic review of the literature concerning the relationship between obesity and mortality in the elderly

INTRODUCTION

Obesity is a risk factor for chronic diseases and premature mortality, but the extent of these associations among the elderly is under debate. The aim of this systematic literature review (SR) is to collate and critically assess the available information of the impact of obesity on mortality in the elderly.

METHODS

In PubMed, there are three-hundred twelve papers on the relationship between obesity and mortality among older adults. These papers were analysed on the basis of their abstracts, and sixteen studies were considered suitable for the purpose of the study. It was possible to perform a pooled estimate for aggregated data in three different studies.

CONCLUSION

The results of this SR document that an increased mortality in obese older adults. The limitation of BMI to index obesity and the noted protective action of a moderate increase in BMI on mortality are highlighted. Waist circumference is an indicator of central adiposity and potentially as good a risk factor for mortality as BMI in obese elderly adults.

Variation in and Correlates of Body Mass Status of Older Singaporean Men and Women

This study describes the body mass status of older (≥60 years) Singaporeans, using the international and Asian body mass index (BMI) classifications, assesses sociodemographic correlates of BMI, underweight, obesity, and “high-risk” BMI (≥27.5 kg/m2), and ascertains the relationship between body mass and important health outcomes. Prevalence of underweight, obesity, and high-risk BMI among 4371 older Singaporeans was 6.8%, 7.4%, and 18.6%, respectively. Women (vs men) and Malays and Indians (vs Chinese) were more likely to have obesity or high-risk BMI. Increasing education decreased the odds of obesity and high-risk BMI only among women. Prevalence and odds of various health conditions was similar in corresponding categories of the two BMI classifications. Whereas the prevalence of obesity is lower among elderly in Singapore than in many other countries, the prevalence of high-risk BMI is considerable. It is important to address high-risk BMI among them, with elderly of minority ethnic groups, especially females, being a priority.

Exceptions to the Rule: Exceptional Health Among the Disadvantaged

Countless studies show that socioeconomic status (SES) is strongly related to morbidity and mortality. However, few studies consider the substantial variability in health within socioeconomic strata. In this article, the authors examine the incompatibility between stratification-based theories of health inequality and empirical patterns of exceptional health among the socially disadvantaged. Using panel data from the Health and Retirement Survey (1992-2008), the authors test the mediating and moderating effects of various predictors of exceptional health (no chronic diseases or physical limitations) for middle-aged and older adults with and without a high school education. Results suggest that a combination of demographic characteristics, family and religious factors, socioeconomic resources, health behaviors, psychological makeup, and biological attributes play differing roles in protecting the health of disadvantaged men and women. The findings underscore the complex associations among SES, protective mechanisms, and health and offer new insight into how disadvantaged adults defy their odds of poor health.

Obesity and mortality among older Thais: a four year follow up study

Background

To assess the association of body mass index with mortality in a population-based setting of older people in Thailand.

Methods

Baseline data from the National Health Examination Survey III (NHES III) conducted in 2004 was linked to death records from vital registration for 2004-2007. Complete information regarding body mass index (BMI) (n = 15997) and mortality data were separately analysed by sex. The Cox Proportional Hazard Model was used to test the association between BMI and all-cause mortality controlling for demographic, socioeconomic, and health risk factors.

Results

During a mean follow-up time of 3.8 years (60545.8 person-years), a total of 1575 older persons, (936 men and 639 women) had died. A U-shaped and reverse J-shaped of association between BMI and all-cause mortality were observed in men and women, respectively. However there was no significant increased risk in the higher BMI categories. Compared to those with BMI 18.5-22.9 kg/m², the adjusted hazard ratios (HR) of all-cause mortality for those with BMI <18.5, 23.0-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, and ≥35.0 were 1.34 (95% CI, 1.14-1.58), 0.79 (95% CI, 0.65-0.97), 0.81 (95% CI, 0.65-1.00), 0.67 (95% CI, 0.48-0.94), 0.60 (95% CI, 0.35-1.03), and 1.87 (95% CI, 0.77-4.56), respectively, for men, and were 1.29 (95% CI,1.04-1.60), 0.70 (95% CI, 0.55-0.90), 0.79 (95% CI, 0.62-1.01), 0.57 (95% CI, 0.41-0.81), 0.58 (95% CI, 0.39-0.87), and 0.78 (95% CI, 0.38-1.59), respectively, for women.

Conclusions

The results of this study support the obesity paradox phenomenon in older Thai people, especially in women. Improvement in quality of mortality data and further investigation to confirm such association are needed in this population.

Resistance Training During Weight Loss in Overweight and Obese Older Adults: What Are the Benefits?

Obesity and sarcopenia are important public health challenges that affect the healthy aging trajectory of older adults. Although weight loss is recommended for overweight and obese older adults to prevent chronic disease, exercise is an important additional weight management strategy to maximize fat mass loss while retaining lean mass and improving function. Resistance training (RT) is a well-known exercise modality to improve muscle function and lean mass and has been investigated in several recent studies as a potentially powerful strategy to employ along with weight loss in overweight and obese older adults. RT is an important exercise training strategy as outlined in the Physical Activity Guidelines for Americans and is recommended by the American College of Sports Medicine for older adults who are able to safely participate. This brief review will highlight some of the age-related consequences of sarcopenia and obesity and will summarize some of the published research findings of combined RT and weight loss in overweight and obese older adults.

The obesity paradox in the elderly: potential mechanisms and clinical implications

The prevalence of overweight and obesity in the elderly has become a growing concern. Recent evidence indicates that in the elderly, obesity is paradoxically associated with a lower, not higher, mortality risk. Although obesity in the general adult population is associated with higher mortality, this relationship is unclear for persons of advanced age and has lead to great controversy regarding the relationship between obesity and mortality in the elderly, the definition of obesity in the elderly, and the need for its treatment in this population. This article examines the evidence on these controversial issues, explores potential explanations for these findings, discusses the clinical implications, and provides recommendations for further research in this area.

Body mass index, disability, and 13-year mortality in older French adults

OBJECTIVE

To investigate the relationship between mortality and BMI in older people, taking into account other established mortality risk factors.

METHODS

A total of 3,646 French community dwellers aged 65 years and older from PAQUID cohort study were included. Cox proportional-hazards analysis was used to assess association between BMI and mortality.

RESULTS

Death occurred in 54.1% of the cohort more than 13 years: 68.99% of the underweight (BMI <19), 52.13% of the obese (BMI >30), 51.66% of the overweight (BMI 25-30), and 51.79% of the reference participants (BMI 22-25) died.The relative risk of death as a function of BMI, adjusted for gender and age, formed a U-shaped pattern, with larger risks associated with lower BMI (<22.0) and for BMI of 25.0 to 30.0 and BMI >/=30. (BMI 22.0-24.9 was the reference.) After adjustment for demographic factors, smoking history, and comorbidity, increased mortality risk persisted in underweight older people, BMI <18.5 and BMI 18.5-22 (respectively, HR = 1.45, 95% CI 1.17-1.78; HR = 1.27, 95% CI 1.12-1.43) compared with reference. Overweight (BMI 25-29.9) and obesity (>/=30) were not associated with increased mortality compared with the reference category (respectively, HR = 0.98, 95% IC 0.88-1.10; HR = 1.06, 95% IC 0.89-1.27). Similar relationships persisted for disabled participant. For nondisabled participant disability did not alter the associations for BMI of 25.0 and higher but for BMI less than 22.0, the risks become insignificantly different from those for the reference group.

DISCUSSION

BMI below 22 kg/ m(2) is a risk factor for 13-year mortality in older people, but our findings suggest that overweight and obesity may not be associated to mortality after adjustment for established mortality risk factors.

Survival in older men may benefit from being slightly overweight and centrally obese--a 5-year follow-up study in 4,000 older adults using DXA

BACKGROUND

Whether overweight in old age is hazardous remains controversial. Body mass index (BMI) overestimates adiposity and fails to measure central adiposity. We used dual-energy x-ray absorptiometry (DXA) to measure adiposity and hypothesized that overall adiposity, distribution of adiposity, and muscle mass might individually affect survival.

METHODS

We recruited 2000 men and 2000 women aged 65 years or older. Baseline BMI, waist-hip ratio (WHR), body fat index (BFI = total body fat/height square), relative truncal fat (RTF = trunk fat/total body fat), and body muscle mass index (BMMI = total body muscle mass/height square) were measured. Mortality was ascertained by death registry after 63.3 (median) months.

RESULTS

Two hundred and forty-two men and 78 women died. In men, mortality hazard ratio (HR) decreased consistently by 0.85 (p < .005), 0.86 (p < .005), and 0.86 (p < .005) per every quintile increase in BMI, BFI, and BMMI, respectively. A J-shaped relationship was observed in central adiposity (RTF and WHR) quintiles; the minimum values were at the 3rd WHR quintile (0.92-0.94) and 4th RTF quintile (mean WHR, 0.94). When RTF was tested with BFI, both high and low central adiposity were unfavorable while general adiposity became marginally insignificant (p = 0.062). When BFI and BMMI were tested together, increasing adiposity rather than muscle mass favored survival (BFI quintile, HR 0.97, p .015; BMMI quintile, HR 1.00, p .997).

CONCLUSIONS

Older men were resistive to hazards of overweight and adiposity; and mild-grade overweight, obesity, and even central obesity might be protective. This may bear significant implication on the recommended cutoff values for BMI and WHR in the older population.

Relationship between angiotensin-converting enzyme gene polymorphism and body composition, functional performance, and blood biomarkers in advanced cancer patients

PURPOSE

Nutritional and functional outcome measures have been shown to vary in patients with chronic diseases according to the polymorphic alleles of angiotensin-converting enzyme (ACE), but little is known about the associations between ACE gene polymorphism (ACEGP) and the components of body composition, strength, and selected blood markers in advanced cancer patients (ACP).

EXPERIMENTAL DESIGN

Data were collected from an inception cohort of 172 newly diagnosed ACP with gastrointestinal and non-small cell lung cancer. ACEGP status was defined by the presence of one of the following three combinations of alleles: insertion/insertion, insertion/deletion, and deletion/deletion. Body composition measurements using Dual-energy X-ray Absorptiometry comprised of the following: total fat mass, percent body fat, lean body mass, and appendicular lean mass. Body mass index; handgrip force by Jamar dynamometry; subjective recording of nutrition and performance status as per patient-generated subjective global assessment; cell blood count and differential, serum albumin, ACE, and C-reactive protein were also recorded.

RESULTS

Multiple regression analysis, controlling for gender, age, diagnosis, treatments (radio/chemo), survival, and medication use (ACE inhibitors, anti-inflammatories, statins) revealed the following significant (P </= 0.05) relationships in the insertion/deletion compared with insertion/insertion group: higher hemoglobin (Hb; beta, 6.39 g/dl; 95% confidence interval, 0.01-12.78), lower total fat mass (-5.78 kg; -11.62 to 0.07), percent body fat (-6.04%; -12.20 to 0.12), and lean body mass (-3.26 kg; -6.78 to 0.26). When comparing the DD to the II group, higher serum ACE (9.10; 1.96-16.25), Hb (6.25 g/dl; -0.63 to 13.12), and handgrip force by Jamar (6.85 lbs; 0.78-12.93) were found.

CONCLUSION

Of the variables studied, ACEGP seems to be primarily associated with differences in body composition, Hb, and muscle strength in ACP. Further data are needed to determine the clinical effect of ACEGP in cancer cachexia.

Convergence of body mass with aging: the longitudinal interrelationship of health, weight, and survival

There has been ongoing debate about the health risks associated with increased body weight among the elderly population. One issue has not been investigated thoroughly is that body weight changes over time, as both the reasons and results of, the development of chronic diseases and functional disabilities. Structural models have the ability to unravel the complicated simultaneous relationship between body weight, disability, and mortality along the aging process. Using longitudinal data from the Medicare Current Beneficiary Survey from 1992 to 2001, we constructed a structural model to estimate the longitudinal dynamic relationship between weight, chronic diseases, functional status, and mortality among the aging population. A simulation of an age cohort from 65 to 100 was conducted to show the changes in weight and health outcomes among the cohorts with different baseline weight based on the parameters estimated by the model. The elderly with normal weight at age 65 experience higher life expectancy and lower disability rates than the same age cohorts in other weight categories. The interesting prediction of our model is that the average body size of an elderly cohort will converge to the normal weight range through a process of survival, senescence, and behavioral adjustment.

Effect of current and midlife obesity status on mortality risk in the elderly

The primary purpose of this study was to determine whether current and midlife obesity status provide independent information on mortality risk in elderly persons. Analyses were based on 3,238 participants from the original Framingham Heart Study (FHS) cohort who lived to at least 70 years of age and who had BMI measures from when they were in their 50s. Within this group of 70-year olds, obesity based on current BMI was associated with a 21% increased risk of mortality (P = 0.019) whereas obesity in 70-year olds based on BMI measures obtained at around 50 years of age was associated with a 55% increased risk of mortality (P < 0.0001). Compared to 70-year olds who were nonobese at both 50 and 70 years of age, mortality risk was increased by 47% (P < 0.001) in those who were obese at both 50 and 70 years of age, increased by 56% (P < 0.001) in those who were obese at 50 years of age and nonobese at 70 years of age, and not significantly different (P > 0.9) in those who were nonobese at 50 years of age and obese at 70 years of age. In summary, in this cohort of elderly adults, midlife and current BMI had independent effects on mortality risk. Specifically, although mortality risk was increased in obese older adults who were already obese at midlife, this was not the case for newly obese older adults. Conversely, nonobese older adults who were obese at midlife had an increased mortality risk. These observations imply that it is imperative to consider an elderly adult's BMI in context of their BMI at midlife.

Health Behaviors and Transitions of Physical Disability Among Community-Dwelling Older Adults

This study examined the transitions of disability over 5 years among older adults and the influences of health behaviors on these transitions. Data was obtained from the community cohort of the National Long-Term Care Survey in 1994 ( n = 5,089) and their follow-up data in 1999. Generalized logit regressions revealed that obesity increased the risk of disability. Light drinking decreased the risk of disability. Among disabled individuals, the risk of status decline was higher for those underweight or physically inactive, and those taking vitamin and/or mineral supplements regularly or working on a hobby were less likely to further decline in the disability statuses. In an older population, having more contacts with friends, having regular social activities, and having a body mass index ≥ 25 were beneficial to survival. These findings indicate that older adults may have greater personal control over their lives based on their choices about lifestyles and social connections.

The financial burden of overweight and obesity among elderly Americans: the dynamics of weight, longevity, and health care cost

OBJECTIVE

To investigate the financial burdens attributed to overweight and obesity on the U.S. health care system among elderly Americans.

DATA SOURCE

Longitudinal Cost and Use files of the Medicare Current Beneficiary Survey from 1992 to 2001.

STUDY DESIGN

We constructed a simultaneous equation system to model the dynamic relationship between changes in body weight, chronic diseases, functional status, longevity, and health care expenditures using maximum likelihood estimation. Based on the estimation, we conducted a simulation of one cohort with different baseline weights at age 65 and followed to death or up to age 100 of their health outcomes and lifetime health care expenditures.

PRINCIPAL FINDINGS

The elderly men who were overweight or obese at age 65 had 6-13 percent more lifetime health care expenditures than the same age cohort within normal weight range at age 65. Elderly women who were overweight or obese at age 65 spent 11-17 percent more than those in a normal weight range. Both elderly men and women who were overweight or obese at age 65 had worse health outcomes than the normal weight cohorts. The average body mass index among survivors decreased by age.

CONCLUSION

Overweight and obesity could place significant financial burdens on the U.S. health care system.

Elevated body mass index and mortality risk in the elderly

The purpose of this report was to perform a systematic review and meta-analysis of the studies examining the impact of an elevated body mass index (BMI) on mortality risk in elderly (> or =65 years) men and women. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality from the 26 analyses that included a risk estimate for a BMI within the overweight range was 1.00 (95% confidence intervals, 0.97-1.03). The summary relative risk of all-cause mortality for the 28 analyses that included a risk estimate for a BMI within the obese range was 1.10 (1.06-1.13). These calculations indicate that a BMI in the overweight range is not associated with a significantly increased risk of mortality in the elderly, while a BMI in the moderately obese range is only associated with a modest increase in mortality risk.

Religious attendance and mortality: implications for the black-white mortality crossover

This study investigates the relationships among religious attendance, mortality, and the black-white mortality crossover. We build on prior research by examining the link between attendance and mortality while testing whether religious involvement captures an important source of population heterogeneity that contributes to a crossover Using data from the Established Populations for Epidemiologic Studies of the Elderly, we find a strong negative association between attendance and mortality. Our results also show evidence of a racial crossover in mortality rates for both men and women. When religious attendance is modeled in terms of differential frailty, clear gender differences emerge. For women, the effect of attendance is race- and age-dependent, modifying the age at crossover by 10 years. For men, however; the effect of attendance is not related to race and does not alter the crossover pattern. When other health risks are modeled in terms of differential frailty, wefind neither race nor age-related effects. Overall, the results highlight the importance of considering religious attendance when examining racial and gender differences in age-specific mortality rates.

Body mass index as a predictor of mortality in community-dwelling seniors

BACKGROUND AND AIMS

The relationship between body mass index (BMI) and mortality remains inconclusive in seniors. This study aimed at assessing this relationship in a community-dwelling elderly population in Japan.

METHODS

The subjects were 371 Japanese elders, 65 years old and older, who lived in a geographically well-defined rural community and had participated in a general health screening program in 1995. Both height and weight of subjects were measured directly by medical staff. Subjects were classified into three groups according to their BMI values: low, <18.5; normal, 18.5-25.0; and high, >25.0. Univariate analysis was applied to explore potential associations between mortality and possible confounders. Multivariate Cox proportional hazards models were used to analyze the association between mortality and BMI, after adjusting for other risk factors.

RESULTS

At baseline, 54 subjects (14.6%) had BMI values in the low range, 280 (75.5%) in the normal range, and 37 (10.0%) in the high range. All 371 subjects were followed prospectively for mortality. Over the next five years, 37 subjects had died. In univariate analysis, male sex, age, BMI and serum creatinine were associated with mortality. The mortality rate in the low BMI group was about twice that in the normal BMI group. No deaths were observed in the higher BMI group. In multivariate analysis, age and low BMI were associated with mortality.

CONCLUSIONS

BMI may be a useful predictor of mortality among seniors living in the general, non-institutionalized population.

Análise crítica do uso do índice de massa corporal para idosos

Esta comunicação discute a utilização do índice de massa corporal, suas limitações e aplicações na avaliação do estado nutricional de idosos. Há um consenso entre os pesquisadores de que um aumento no peso corporal em indivíduos de idade mais avançada seja aconselhável, mudando os pontos de corte até então utilizados. Atualmente, recomendam-se pontos de corte para definição de baixo peso (índice de massa corporal <22kg/m²), eutrofia (índice de massa corporal entre 22 a 27kg/m²) e sobrepeso (índice de massa corporal >27kg/m²) que diferem dos valores recomendados para adultos e freqüentemente utilizados para idosos. Esta proposta leva em consideração as mudanças na composição corporal que ocorrem com o envelhecimento. Apesar de não representar a composição corporal dos indivíduos, a facilidade de obtenção de dados de peso e estatura bem como sua boa correlação com morbidade e mortalidade justificam a utilização do índice de massa corporal em estudos epidemiológicos e na prática clínica desde que se usem pontos de corte específicos para a idade, especialmente se associados a outras medidas antropométricas que expressem a composição e a distribuição da gordura corporal.

An adequate threshold for body mass index to detect underweight condition in elderly persons: the Italian Longitudinal Study on Aging (ILSA)

BACKGROUND

The present study aims at defining a body mass index (BMI) threshold for risk of being underweight in elderly persons on the basis of the BMI distribution in a large Italian population-based sample and on its ability to predict short-term mortality.

METHODS

At baseline (1992), BMI was obtained for 3110 (1663 males and 1447 females) persons aged 65-84 participating in the Italian Longitudinal Study on Aging (ILSA). BMI and risk factors (age, sex, education, smoking status, disability, and disease status) have been considered for their potential association with 4-year all-cause mortality. Information on vital status at 1995 was obtained for 2551 participants.

RESULTS

The fifth centile of BMI was well approximated by a value of 20 for both sexes. Also in both sexes, at a BMI value of 24 the a posteriori probability of death started to increase, doubling at a value of 22 for men and 20 for women. Crude mortality was 14.6% for men and 9.8% for women. The hazard ratios and confidence intervals (CIs) comparing mortality for each BMI two-unit class to the 26-28 class, after adjusting for confounding variables, showed significantly higher rates only for BMI values below 20 (2.9; 95% CI, 1.2-7.0), although a consistent increase in hazard ratio (1.6; 95% CI, 0.9-3.0) already appeared for the 20-22 BMI group.

CONCLUSIONS

Our study confirms that low BMI is an independent predictive factor of short-term mortality in elderly persons. A BMI value of 20 kg/m2 seems to be a reliable threshold for defining underweight elderly persons at high risk. Nevertheless, more careful clinical and nutritional management should also be applied to elderly persons with higher BMI values.

The Bicycle Makes the Eyes Smile: Exercise, Aging, and Psychophysical Well-Being in Older Italian Cyclists

Despite a cultural and biomedical consensus about the health benefits of physical activity, most adults do not exercise regularly and their activity tends to decline further in older age. This study reports on a group of older-age Italian bicyclists who maintain extraordinary activity levels. It explores the physical and mental health effects of intensive exercise in older people, the meanings and motivations associated with it, and the cultural and social features that support and promote bicycling in Italy. The findings suggest some public health implications for the prevention of chronic diseases caused by inactivity and excessive body weight.

Body mass index and old-age survival: A comparative study between the Union Army Records and the NHANES-I Epidemiological Follow-Up Sample

On the basis of a historical review of the BMI trend among white male Americans since the late 19th century, this paper investigates the association between BMI measured at age 50-59 years and survival in the subsequent 18 years of follow-up through a comparative study between the Union Army Records (n = 1,238) and the 1971-1975 National Health and Nutritional Examination Survey Epidemiological Follow-up Sample (n = 861). A descriptive analysis of the trend in BMI suggests that the age-adjusted average BMI among adult white males has increased from 22.8 in the late 19th century to 28.0 in the year of 2000. The corresponding increase in the age-adjusted percentage of obesity is from 2.5% to 28.2%. Given the significant increase in BMI, it becomes important to evaluate how the BMI-mortality association has changed since the 19th century, and what implications these changes might have to mortality in the future. The results from the Cox proportional hazard analysis indicate that as the average BMI at population level increases, the optimal BMI in terms of survival increases, rather than stable. With the whole American population moving into a higher BMI regime, the optimal BMI in terms of old-age survival for white male Americans has experienced a substantial upward shift, from 20.6-23.6 in the late 19th century to 22.7-27.3 in the early 1970s. Mortality differentials across BMI quintiles have become more salient since the late 19th century. There is still good potential for old-age mortality to further decline. However, to what extent this potential can be developed will partially depend on the future trend in the prevalence of obesity.

The nutritional status of 1081 elderly people residing in publicly funded shelter homes in Peninsular Malaysia

OBJECTIVES

The aim of this study was to determine the: (1) prevalence of undernutrition as determined by the 'DETERMINE Your Nutritional Health Checklist' (NHC) and (2) factors independently associated with undernutrition among the older residents of these publicly funded shelter homes in Peninsular Malaysia.

DESIGN

A total of 1081 elderly people (59%M) over the age of 60 y were surveyed using questionnaires determining baseline demographics, nutritional and cognitive status, physical function and psychological well-being.

SETTING

Shelter homes, Peninsular Malaysia.

RESULTS

In all, 41.4% (n = 447) were nourished (score <3), 32.1% (n = 347) at moderate risk (score between 3 and 5) and 26.6% (n = 287) were at high risk of undernutrition (score>5) according to the NHC. A large proportion of subjects were underweight with 14.3% of subjects recording a low body mass index (BMI) <18.5 kg/m2 and a further 18.2% recording a BMI between 18.5 and 20 kg/m2. The residential geriatric depression score (GDS-12R) (relative risk (RR) = 1.03 (95% confidence interval (CI) 1.01-1.05); P = 0.002) and the number of illnesses (RR = 1.14 (95% CI 1.07-1.21); P < 0.001) were found to be independently associated with nutritional risk (NHC score > or = 3). Using a BMI < 18.5 kg/m2 as an objective marker for nutritional risk, the NHC was shown to have a sensitivity of 66.4% (95% CI 58.0-74.2%), specificity of 42.7% (95% CI 39.3-46.1%), positive predictive value of 16.2% (95% CI 13.3-19.5%) and a negative predictive value of 88.4% (95% CI 84.9-91.4%).

CONCLUSIONS

Many elderly people residing in publicly funded shelter homes in Malaysia may be at-risk of undernutrition, and were underweight. The NHC is better used as an awareness tool rather than as a screening tool.

Impact of age on definition of standards for ideal weight

There has been an ongoing debate regarding the impact of age while establishing standards for ideal weight. Based on current federal guidelines released by the National Heart, Lung, and Blood Institute, ideal weight is defined as a body mass index between 18.7-24.9 for all adults regardless of age. However, studies failed to show a positive association between overweight--as defined by the current guidelines--and all-cause and cardiovascular mortality in individuals 65 years and older. Data suggest that optimum body mass index tended to be higher for older adults compared with the young and middle-aged population, and interestingly, being heavier than recommended by the current guidelines resulted in the lowest mortality rates. Therefore, allocation of time and resources for weight reduction interventions among the mild- to moderately-overweight elderly is not advisable. To establish standards for ideal weight, future guidelines should consider age-specific recommendations that reflect the results of recent studies.

Facilitated feeding in disabled elderly

Nutrition and health are major concerns to older individuals. Whereas illness associated with overnutrition has been well characterized, poor health associated with undernutrition has received less attention. Malnutrition continues to plague the elderly in developed and underdeveloped countries alike, and is becoming of more concern as global demographic changes predict increasing proportions of elderly in all societies. Nutrition influences many chronic disease processes affecting older individuals. In addition, changes in physiology, metabolism, and function accompanying aging result in altered nutritional requirements. The enhancement and maintenance of health and function are now more possible with the new knowledge of nutritional needs in old age. Designing nutritional therapy to treat malnutrition associated with illness in older patients requires an understanding of the aging processes, a careful setting of treatment goals, and multidisciplinary collaboration.