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

BMI trajectory in adulthood in relation to all-cause and cause-specific mortality: A retrospective cohort study in Taiwan

A dynamic change of weight over time has been known as an important factor that impacts mortality risk. The aims of this study were to identify the heterogeneity of BMI trajectory groups and to examine the association of the trajectories of BMI and all-cause and cause-specific mortality. The data for this study were obtained from a large prospective cohort study in Taiwan between 1998 and 2019 that was linked to the National Death Registry for death information. The participants were stratified into four groups by age and gender; self-reported demographics and measured BMI data were used. We used group-based trajectory analysis to identify the distinct trajectories of changes in BMI. A Cox proportional hazards model was used to assess the hazard ratio (HR) of all-cause and cause-specific mortality risk. Data were analyzed in April 2020 and included 89,886 participants. Four trajectory groups were identified by the pattern of BMI change over time. Our study shows that different trajectories were associated with mortality. Our findings suggest that the mortality risk differs in each trajectory group and in each age and gender stratification. It appears that obesity is a protective factor in cancer-related mortality in females but not in males in group of old age participants; low-normal weight is a risk factor in respiratory-related mortality in all participants. Our findings can be used to suggest the appropriate BMI in each age and gender groups and thereby earlier health interventions can be taken to avoid mortality.

Nutritional Status Assessed with Objective Data Assessment Correlates with a High-Risk Foot in Patients with Type 2 Diabetes

Malnutrition and diabetes are likely to co-occur. There are few reports on the association between nutritional status and foot risk in patients with type 2 diabetes (T2D). Therefore, we aimed to investigate this relationship in this cross-sectional study. We investigated the relationships between objective data assessment (ODA), especially Controlling Nutritional Status (CONUT) score and foot risk, evaluated by the International Working Group on the Diabetic Foot (IWGDF), in consecutive patients with T2D. Patients were divided into groups 0 to 3 by IWGDF, and groups 1 to 3 were defined as high-risk groups. Among 469 patients, 42.6% (n = 200) of them had high-risk foot. Patients with high-risk foot were significantly older (71.2 ± 11.3 vs. 64.2 ± 13.4 years, p < 0.001) and had a longer duration of diabetes (18.0 ± 12.0 vs. 11.5 ± 10.0 years, p < 0.001) than those in the low-risk group. In the high-risk group, serum albumin level, total lymphocyte count, hemoglobin, and CONUT score were significantly worse, especially in older patients (≥75 years). Multivariate logistic regression analysis showed that there was a positive correlation between CONUT score and high-risk foot in older patients (OR, 1.37; 95% CI, 1.05−1.86; p = 0.021). Our results indicated that nutritional status, assessed by ODA, correlated with high-risk foot, especially in older patients with T2D.

Body mass index and mortality among community-dwelling elderly of Southern Brazil

This study aims to measure the association between body mass index (BMI), comparing two different classifications, and mortality among community-dwelling elderly considering myopenia in Pelotas, Brazil. This is a longitudinal study started in 2014, we followed 1451 elderly people (≥ 60 years) enrolled in the "COMO VAI?" study. BMI was classified according to the World Health Organization (WHO) and the classification with specific cutoff points for older adults. Myopenia was measured by calf circumference (≤33 cm for women and ≤34 cm for men). Cox proportional-hazards models were used to test associations controlling for sociodemographic and behavioral characteristics and number of morbidities. Nearly 10% (N = 145) of the elderly died during almost three years of follow-up. We observed a L-shaped relation between BMI and mortality. Elderly with underweight had a higher mortality risk compared to those with adequate BMI in both classifications. According to the WHO classification, overweight elderly presented protection for mortality (HR: 0.58; 95% CI 0.38-0.87) when compared to those with adequate BMI. Among elderly with myopenia, overweight by WHO continued to protect against mortality, although not significantly, while those with the specific classification underweight presented a higher risk of death compared to those with normal weight (HR: 2.09; 95% CI 1.06-4.14). In conclusion the underweight increased the risk of death in community-dwelling elderly people during a follow-up of three years. The specific classification seemed to be more adequate to indicate risk of mortality in this population. Higher BMI protect against mortality when muscle mass was not considered.

Heterogeneity in Trajectories of Body Mass Index and Their Associations with Mortality in Old Age: A Literature Review

This article reviewed studies to investigate the association between trajectories of body mass index (BMI) and mortality among older adults. Investigators conducted a systematic search of published peer-reviewed literature in the PubMed database, and three articles that satisfied the inclusion criteria for the review were identified. All of these studies used group-based trajectory models to identify distinct BMI trajectories. Two studies were derived from the U.S. and used data from the Health and Retirement Study, with up to nine repeated observations. Most of the BMI trajectories in older Americans were increasing and fell primarily within the overweight and obese ranges. The other study was from Japan and used nationwide data, with up to seven repeated observations. BMI trajectories identified in the older Japanese were mostly decreasing and fell primarily within the normal weight range. Although the distribution of BMI trajectories was different between the two nations, the findings from these three studies consistently demonstrated that people with stable overweight trajectories had the lowest all-cause mortality rates in both countries. Beyond this, however, these studies suggested that priorities for weight control in old age should likely differ between Western and non-Western countries. Research regarding BMI trajectories and mortality in old age is very limited at present. Evidence from countries other than the U.S. and Japan is warranted in order to validate current findings and guide the development of local clinical and public health strategies for body weight management aimed at improving the health and survival of older adults.

Trajectories of Body Mass Index and Their Associations With Mortality Among Older Japanese: Do They Differ From Those of Western Populations?

Few studies have focused on the relationship between the trajectories of long-term changes in body mass index (BMI; weight (kg)/height (m)(2)) and all-cause mortality in old age, particularly in non-Western populations. We evaluated this association by applying group-based mixture models to data derived from the National Survey of the Japanese Elderly, which included 4,869 adults aged 60 or more years, with up to 7 repeated observations between 1987 and 2006. Four distinct BMI trajectories were identified: "low-normal weight, decreasing" (baseline BMI = 18.7; 23.8% of sample); "mid-normal weight, decreasing" (baseline BMI = 21.9; 44.6% of sample); "high-normal weight, decreasing" (baseline BMI = 24.8; 26.5% of sample); and "overweight, stable" (baseline BMI = 28.7; 5.2% of sample). Survival analysis with an average follow-up of 13.8 years showed that trajectories of higher BMI were associated with lower mortality. In particular, relative to those with a mid-normal weight, decreasing BMI trajectory, those with an overweight, stable BMI trajectory had the lowest mortality, and those with a low-normal, decreasing BMI trajectory had the highest mortality. In sharp contrast with prior observations from Western populations, BMI changes lie primarily within the normal-weight range, and virtually no older Japanese are obese. The association between BMI trajectories and mortality varies according to the distribution of BMI within the population.

High serum adiponectin concentration and low body mass index are significantly associated with increased all-cause and cardiovascular mortality in an elderly cohort, "adiponectin paradox": the Korean Longitudinal Study on Health and Aging (KLoSHA)

BACKGROUND

The relationship between adiponectin concentration and mortality is unclear. We examined whether serum adiponectin concentration is associated with all-cause and cardiovascular mortality in elderly Asians.

METHODS

We analyzed the data for community-dwelling adults ≥65 years of age (439 men and 561 women) who were enrolled in the Korean Longitudinal Study on Health and Aging (KLoSHA) cohort in prospective manner. The baseline serum total and high molecular weight adiponectin were measured using an enzyme-linked immunosorbent assay. Using Cox regression, we determined the associations between serum adiponectin concentration and all-cause and cardiovascular mortality after adjusting for well-known cardiovascular risk factors.

RESULTS

Over a mean follow-up time of 6.2 years, 222 individuals died, and 52 deaths (23.4%) were by cardiovascular disease. After adjusting confounding factors, elevated baseline serum adiponectin concentration was independently associated with all-cause mortality (adjusted hazard ratio [HR] 1.38; 95% confidence interval [CI] 1.17-1.64) and cardiovascular mortality (HR 1.50; 1.06-2.14). We evaluated the effect modification by baseline body mass index (BMI). High serum adiponectin and low BMI were synergistically associated with increased all-cause mortality (HR 6.25; 3.08-12.71) and cardiovascular mortality (HR 13.94; 1.82-106.58).

CONCLUSIONS

Higher serum adiponectin concentration was associated with increased all-cause and cardiovascular mortality in community-dwelling elderly Asian population. Our data supported the recent theory so called "adiponectin paradox". This relationship was strengthened when combined with low BMI. We suggest that measurement of adiponectin concentration and BMI together could be an additional predictive marker of survival among elderly adults.

Body mass index and disease-specific mortality in an 80-year-old population at the 12-year follow-up

Although many investigations examined the relationship between body mass index (BMI) and mortality, little is known about the possible associations between BMI and disease-specific mortality in very elderly people. Here we evaluated this association in an 80-year-old population. In 1998, 675 residents in Japan's Fukuoka Prefecture participated. They were followed up for 12 years after the baseline examination; 37 subjects (5.5%) were lost to follow-up. The subjects were divided into six groups by their BMI values: <19.5 (most-thin), 19.5 to <21.1 (relatively thin), 21.1 to <22.5 (thin/normal), 22.5 to <23.8 (normal/overweight), 23.8 to <26.0 (relatively obese), ≥26.0 (most-obese). The most-thin group had the highest mortality from all-causes, and from respiratory disease. The normal/overweight group had the lowest overall mortality among the six BMI groups. These associations were found in the men, but not in the women. The most-obese group did not have higher mortality from all-causes or cardiovascular disease compared to the normal/overweight group. Respiratory disease-related mortality was lowest in the most-obese group. No association was found between BMI group and mortality from cancer. In conclusion, in an 80-year-old Japanese population, mortality from all-causes or respiratory disease was highest in the most-lean group (BMI <19.5), and mortality from all-causes or cardiovascular disease was lowest in the group with BMI 22.5 to <23.8.

BMI and all-cause mortality among Japanese older adults: findings from the Japan collaborative cohort study

The association between BMI and all-cause mortality may vary with gender, age, and ethnic groups. However, few prospective cohort studies have reported the relationship in older Asian populations. We evaluated the association between BMI and all-cause mortality in a cohort comprised 26,747 Japanese subjects aged 65-79 years at baseline (1988-1990). The study participants were followed for an average of 11.2 years. Proportional-hazards regression models were used to estimate mortality hazard ratios (HRs) and 95% confidence intervals. Until 2003, 9,256 deaths occurred. The underweight group was associated with a statistically higher risk of all-cause mortality compared with the mid-normal-range group (BMI: 20.0-22.9); resulting in a 1.78-fold (95% confidence interval: 1.45-2.20) and 2.55-fold (2.13-3.05) increase in mortality risk among severest thin men and women (BMI: <16.0), respectively. Even within the normal-range group, the lower normal-range group (BMI: 18.5-19.9) showed a statistically elevated risk. In contrast, being neither overweight (BMI: 25.0-29.9) nor obese (BMI: > or =30.0) elevated the risk among men; however among women, HR was slightly elevated in the obese group but not in the overweight group compared with the mid-normal-range group. Among Japanese older adults, a low BMI was associated with increased risk of all-cause mortality, even among those with a lower normal BMI range. The wide range of BMI between 20.0 and 29.9 in both older men and women showed the lowest all-cause mortality risk.

Body mass index is inversely related to mortality in elderly subjects

PURPOSE

To study the long-term effect of being overweight on mortality in very elderly subjects.

METHODS

The medical records of 470 inpatients (226 males) with a mean age of 81.5 +/- 7 years and hospitalized in an acute geriatric ward between 1999 and 2000 were reviewed for this study. Body mass index (BMI) at admission day was subdivided into quartiles: <22, 22-25, 25.01-28, and > or =28 kg/m(2). Patients were followed-up until August 31, 2004. Mortality data were taken from death certificates.

RESULTS

During a mean follow-up of 3.46 +/- 1.87 years (median 4.2 years [range 1.6 to 5.34 years]), 248 patients died. Those who died had lower baseline BMI than those who survived (24.1 +/- 4.2 vs 26.3 +/- 4.6 kg/m(2); p < .0001). The age-adjusted mortality rate decreased from 24 to 9.6 per 100 patient-years from the highest to lowest BMI quartile (p < .001). BMI was associated with all-cause and cause-specific mortality even after controlling for sex. A multivariate Cox proportional hazards model identified that even after controlling for male gender, age, renal failure, and diabetes mellitus, which increased the risk of all-cause mortality, elevated BMI decreased the all-cause mortality risk.

CONCLUSIONS

In very elderly subjects, elevated BMI was associated with reduced mortality risk.