Association between Adiposity and disability in the Lc65+ Cohort.

Area of Science:

• Gerontology
• Epidemiology
• Public Health

Background:

• Obesity, indicated by high body mass index (BMI) and waist circumference (WC), is a growing concern in aging populations.
• Understanding the association between excess weight and health outcomes like mortality and disability is crucial for public health interventions.

Purpose of the Study:

• To investigate the longitudinal relationship between body mass index (BMI) and waist circumference (WC) and their impact on mortality and incident disability.
• To analyze these associations within the Lc65+ cohort, a population-based study of older adults.

Main Methods:

• A population-based cohort of 1,293 non-institutionalized adults (aged 65-70 at baseline) in Lausanne, Switzerland, was followed for up to 8.9 years.
• Body mass index (BMI) and waist circumference (WC) were measured at baseline. Mortality and disability (difficulty with basic activities of daily living or institutionalization) were assessed annually.
• Cox regression models were used to analyze the association between BMI/WC quintiles and outcomes, adjusting for relevant covariates.

Main Results:

• Over a median follow-up of 8.47 years, 130 participants died. Neither BMI nor WC showed a significant association with mortality, though trends suggested non-significant J-curves.
• Disability incidence increased with higher BMI and WC quintiles. Significantly higher risks of disability were observed for the highest BMI quintile (HR=2.44) and highest WC quintiles (HR=1.81-2.58).

Conclusions:

• Nearly half the participants with higher BMI or WC faced a substantially increased risk of disability compared to reference groups.
• These findings highlight the importance of lifelong strategies, including adequate nutrition and physical activity, to prevent excess weight, muscle loss, and functional decline in older adults.