Does abdominal obesity accelerate muscle strength decline in older adults? Evidence from the English Longitudinal Study of Ageing.

Background: Cross-sectional evidence has shown an association between abdominal obesity and lower muscle strength in older adults. However, no longitudinal findings have confirmed this association. In addition, the impact of abdominal fat on the reduction in muscle strength is not yet fully understood.

Methods: We investigated the longitudinal associations between abdominal obesity and handgrip strength in 5,181 older adults from the English Longitudinal Study of Ageing (ELSA) over eight years of follow-up. Muscular strength was measured using a manual dynamometer. Abdominal obesity was defined as a waist circumference >102cm for men and >88cm for women. Generalized linear mixed models were adjusted by measures of socioeconomic status, health conditions, lifestyle, cognition, depressive symptoms, biomarkers and disability.

Results: At baseline, the mean age of participants was 65.8 years and their mean waist circumference and BMI were 95 cm and 27.7 kg/m², respectively. Fully adjusted models showed that abdominal obese men and women had stronger muscle strength at baseline. The decline over time in muscle strength was accelerated in abdominal obese men (-0.12 kg per year, 95%CI = -0.24 - -0.01) compared to non-abdominal obese. This association was not found in women. Comparative analyses showed that overweight men according to their body mass index were not at greater risk of muscle strength decline. However, these men were at risk based on their waist circumference.

Conclusions: Abdominal obesity is associated with accelerated muscle strength decline in men.