Comparison of body mass index range criteria and their association with cognition, functioning and depression: a cross-sectional study in Mexican older adults

BACKGROUND

World population is living longer, demanding adjustments in public health policies. Body mass index (BMI) is widely known and used as a parameter and predictor of health status although an adapted criterion for older adults is usually overlooked. BMI has been extensively analysed in relation to mortality but fewer studies address its association with cognition, functioning and depression in older adults. The present study aimed at 1) comparing BMI distribution according to the ranges proposed by the World Health Organization (WHO) and the United States National Research Council Committee on Diet and Health (CDH), 2) analysing their association with cognitive functioning, physical functioning and depression and 3) analysing a possible, interaction of BMI criteria with sex on the outcome measures.

METHODS

This cross-sectional study included 395 participants recruited by convenience sampling; 283 (71.6%) women and 112 (24.58%) men. Mean age was 74.68 (SD = 8.50, range: 60-98). Outcome measures included the Short Portable Mental State Questionnaire for cognitive status, the Barthel's Index of Activities of Daily Living for physical functioning, and the Geriatric Depression Scale.

RESULTS

WHO criterion classified most cases (65.3%) as overweight, followed by normal weight (32.2%) and underweight (2.5%) whereas CDH criterion considered most (48.1%) as normal weight, and followed by overweight (31.4%) and underweight (20.5%). Analysing cognitive status, independent physical functioning and depression mean scores, significant differences (p ≤ .001) were found when comparing the three weight groups (underweight, normal weight and overweight) using either the WHO- or the CDH criterion. Post-hoc tests revealed that in all comparisons the underweight group scored the lowest in all three outcome measures. According to the CDH criterion, overweight was favourable for females but unfavourable for males regarding cognitive status (interaction F(2,389) = 4.52, p ≤ .01) and independent functioning (interaction F(2,389) = 3.86, p ≤ .05).

CONCLUSIONS

BMI and its associations to relevant outcome measures in the older adults must rely on criteria that take into account the particular features of this population, such as the CDH criterion. Underweight was associated with decremented cognition, less independent physical functioning and more depression. Overweight seemed favourable for women but unfavourable for men.

Cardiometabolic and Inflammatory Biomarkers as Mediators Between Educational Attainment and Functioning at the Age of 90 Years

BACKGROUND

Low socioeconomic status is associated both with poorer functioning and elevated levels of inflammatory and cardiometabolic biomarkers; however, knowledge of such relations for the oldest old is limited. Our aim was to study whether education is associated with cardiometabolic (cholesterol levels, body mass index, and leptin) and inflammatory (C-reactive protein, interleukin-6, interleukin-1Ra) biomarkers for the 90-year-olds who participated in the Vitality 90+ study. In addition, we investigated whether these biomarkers explain educational inequalities in functioning.

METHODS

All persons in Tampere, Finland, who were born in 1909 or 1910, were invited to participate, irrespective of their health status or dwelling place. The sample consisted of 262 participants who went through the home interview and blood tests. The socioeconomic status indicator used was the highest education, and physical functioning was assessed using the Barthel index. The association of education with individual and combined biomarker scores, and with functioning, was analyzed cross-sectionally applying generalized linear models.

RESULTS

The low- and mid-level-educated participants had greater odds of belonging to the high risk group in cardiometabolic biomarkers than did the high-educated. Differences were statistically significant in three individual biomarkers (high-density lipoprotein-cholesterol, leptin, and body mass index) and in a cardiometabolic score. There were no educational differences in inflammatory biomarkers. When all biomarkers were combined, they mediated educational differences in functioning on an average of 23%. After controlling for smoking, alcohol use and diseases, biomarkers mediated part of the differences between the mid-level- and high-educated.

CONCLUSIONS

High education was associated with better cardiometabolic biomarkers and functioning among the 90-year-olds. In part, educational inequalities in functioning were explained by cardiometabolic biomarkers.

Becoming centenarians: disease and functioning trajectories of older US Adults as they survive to 100

BACKGROUND

Little is known about the health and functioning of individuals who become centenarians in the years prior to reaching age 100. We examined long-term trajectories of disease, disability, and cognitive function in a sample of U.S. centenarians to determine how their aging experience differs from their nonsurviving cohort counterparts, and if there is heterogeneity in the aging experience of centenarians.

METHODS

Data are from the 1993-2010 waves of the nationally representative Health and Retirement Study. Among those who had the potential to become centenarians, we identified 1,045 respondents who died before reaching age 100 and 96 who survived to their 100th birthday. Respondents, or their proxies, reported on diagnosis of six major diseases (hypertension, heart disease, lung disease, stroke, cancer, and diabetes), limitations in activities of daily living, and cognitive function.

RESULTS

As they age to 100, centenarians are generally healthier than nonsurviving members of their cohort, and a number of individuals who become centenarians reach 100 with no self-reported diseases or functional impairments. About 23% of centenarians reached age 100 with no major chronic disease and approximately the same number had no disability (18%). Over half (55%) reached 100 without cognitive impairment. Disease and functioning trajectories of centenarians differ by sex, education, and marital status.

CONCLUSIONS

While some centenarians have poor health and functioning upon reaching age 100, others are able to achieve exceptional longevity in relatively good health and without loss of functioning. This study underscores the importance of examining variation in the growing centenarian population.