Multinational evaluation of anthropometric age (AnthropoAge) as a measure of biological age in the USA, England, Mexico, Costa Rica, and China: a population-based longitudinal study.

OBJECTIVE: To validate AnthropoAge, a new metric of biological age (BA), for prediction of all-cause mortality and age-related outcomes and characterize population-specific aging patterns using multinational longitudinal cohorts. METHODS: We analyzed harmonized multinational data from the Gateway to Global Aging, including studies from the US, England, Mexico, Costa Rica, and China. We used body mass index and waist-to-height ratio to estimate AnthropoAge and AnthropoAgeAccel in participants aged 50-90 years old as proxies of BA and age acceleration, respectively. We compared the predictive capacity for all-cause mortality of AnthropoAge and chronological age (CA) using Cox models, described aging trends in all countries and explored the utility of longitudinal assessments of AnthropoAgeAccel to predict new-onset functional decline and age-related diseases using generalized estimating equations (GEE). FINDINGS: Using data from 55,628 participants, we found AnthropoAge (c-statistic 0.772) outperformed CA (0.76) for prediction of mortality independently of comorbidities, sex, race/ethnicity, education, and lifestyle; this result was replicated in most countries individually except for Mexico. Individuals with accelerated aging had a ~39% higher risk of death, and AnthropoAge also identified trends of faster biological aging per year. In longitudinal analyses, higher AnthropoAgeAccel values were independently predictive of self-reported health deterioration and new-onset deficits in basic/instrumental activities of daily living (ADL/IADL), diabetes, hypertension, cancer, chronic lung disease, myocardial infarction, and stroke. CONCLUSIONS: AnthropoAge is a robust and reproducible BA metric associated with age-related outcomes. Its implementation could facilitate modeling trends of biological aging acceleration in different populations, although recalibration may enhance its utility in underrepresented populations such as individuals from Latin America.

Functional limitation among middle age and older adults: Exploring cross-national gender disparities.

OBJECTIVE: Functional limitations are prevalent among aging demographics, especially women. Structural and health factors, which vary worldwide, influence rates of functional limitations. Yet, gender disparities in functional limitation remain unclear in a global context. METHODS: We use 2018 data from the Health and Retirement Study (HRS) international family of studies with respondents ages 50-64 and (n = 87,479) and 65-89 (n = 92,145) to investigate gender disparities in large muscle functional limitation (LMFL) across 10 countries/regions using mixed effects logistic regression, with special attention to structural indicators of inequality and health. RESULTS: Among both women and men, LMFL was generally higher in China, India, Mexico, United States, and Baltic States than in England, Scandinavia, Southern Europe, Eastern Europe, and Western Europe. The gender disparity in LMFL gradually declined at older ages in India, China, Mexico, and United States, while this disparity gradually increased at older ages throughout Europe. Among middle age respondents, the greater risk of LMFL for women in countries/regions with a high GII was no longer observed after accounting for comorbidities. Among older respondents, a lower risk of LMFL for women in countries/regions with a high GII was not observed until accounting for comorbidities. DISCUSSION: Our findings suggest that rates of LMFL are higher in middle-income countries than high-income countries, especially among women, and in countries with a higher GII. In addition, consideration of comorbidities was integral to these relationships. Thus, national/regional contexts inform differential rates of functional limitation, particularly as it relates to gender.

Associations Between Physical Function and Subjective Well-Being in Older Adults From Low- and Middle-Income Countries: Results From the Study on Global AGEing and Adult Health (SAGE).

BACKGROUND: Physical function is positively associated with subjective well-being in older adults from high-income nations. This study tests whether this association is evident in low- and middle-income countries. METHODS: Data were drawn from the study on global AGEing and adult health, using nationally representative samples of individuals over 50 years old from China, Ghana, India, Mexico, Russia, and South Africa. Participant interviews measured well-being (quality of life, mood, and happiness) and physical function (grip strength, usual and rapid gait speed). Logistic regressions tested relations between physical function and well-being variables within each country. RESULTS: Higher physical function measures exhibited moderate, yet significant, associations with increased odds of highly rated well-being (p < .05). However, higher gait speeds were unexpectedly associated with decreased odds of highly rated well-being (p < .05) in South Africa and Russia. CONCLUSION: These results suggest that physical function is generally positively associated with perceived well-being in older individuals from lower income nations.

The association between social support and cognitive function in Mexican adults aged 50 and older.

Social support networks are crucial for the health of older adults; however, personal characteristics and time of life may diminish the protective effect of social support. OBJECTIVE: to determine if the presence of social support networks were associated with cognitive impairment among Mexican adults aged 50 or older and if this relationship was different based on age. METHOD: This study analyzed data from the National Representation Survey performed in Mexico, Study on Global Ageing (SAGE) wave 1. Cognitive function was evaluated by a standardized test, social support was evaluated through latent class analysis (LCA). The LCA was run to obtain three subgroups of different Social Support Levels (SSL): low, medium, and high. Logistic regression models, stratified by age, were performed to analyze the association between SSL and cognitive function. RESULTS: For respondents ages 71-80 y/o, there was an inverse relationship with cognitive impairment for those with medium (OR 0.23, p=0.020) and high (OR 0.07, p=0.000) SSL in comparison with low SSL. While social support helped to improve cognitive function in older adults aged 71-80, this same association was not observed in adults of other ages. Those younger than 70 y/o may not need such a strong support network as a result of being more self-sufficient. After 80, social networks were not enough to help diminish the negative impact of cognitive impairment. CONCLUSION: Social support could improve the cognitive function of adults ages 71 and 80; suggesting there could be a window of opportunity to improve cognitive functioning for this group.