Abdominal obesity as a risk factor for disability in Brazilian older adults

Objective: To assess the role of abdominal obesity in the incidence of disability in older adults living in São Paulo, Brazil, in a 5-year period.

Design: Longitudinal study, part of the SABE Study (Health, Wellbeing and Aging). We assessed the disability incidence in the period (reported difficulty in at least one activity of daily living (ADL) in 2010) in relation to abdominal obesity in 2006 (waist circumference ≥102 cm in men and ≥88 cm in women). We used Poisson regression to evaluate the association between obesity and disability incidence, adjusting for sociodemographic and clinical factors including BMI.

Setting: São Paulo, Brazil.

Subjects: Older adults (n 1109) who were independent in ADL in 2006. In 2010, 789 of these were located and re-interviewed.

Results: The crude disability incidence (at least one ADL) was 27·1/1000 person-years in the period. The incidence rate was two times higher in participants with abdominal obesity compared with those without (39·1/1000 and 19·4/1000 person-years, respectively; P<0·001). This pattern was observed in all BMI levels. In regression models, abdominal obesity remained associated with disability incidence (incidence rate ratio=1·90; P<0·03), even after controlling for BMI, gender, age, low grip strength, cognitive impairment, physical inactivity and chronic diseases.

Conclusions: Abdominal obesity was strong risk factor for disability, showing a more significant effect than BMI, and thus should be an intervention target for older adults. Waist measure is simple, cost-effective and easily interpreted, and therefore can be used in several settings to identify individuals at higher risk of disability.