Gender differences in trajectories of lower extremity function in older adults: findings from the International Mobility in Aging Study

Objectives: We examined the lower extremity function trajectories of older men and women over 4 years and baseline predictors of these trajectories. 

Design: Longitudinal analysis of an international cohort study. 

Settings and participants: Older adults from the International Mobility in Aging Study (IMIAS) aged between 65 and 74 years at baseline. 

Measures: Physical performance of the lower extremities was measured in 2012, with follow-ups in 2014 and in 2016, using the Short Physical Performance Battery (SPPB). Group-based trajectory analysis of physical performance by gender was performed. Multinomial logistic regression was used to derive relative risk ratios with 95% confidence intervals between the physical performance trajectories and the potential baseline predictors in men and women separately. 

Results: Three physical performance trajectories were identified in men and women: high-stable (30.0% vs 35.5%), gradual functional decline (63.1% vs 54.3%), and rapid functional decline (6.9% vs 10.2%). Common baseline characteristics associated with memberships in the gradual functional decline and rapid functional decline trajectory groups in men and women were age, single marital status, and multiple chronic conditions (>3). Among men, depression was a strong predictor of the membership in the rapid functional decline trajectory group. Women in the rapid functional decline trajectory group were more likely to be obese, with feminine and undifferentiated gender roles, and have poor self-rated health at baseline. 

Conclusions/Implications: There are gender differences in the physical performance trajectories and related factors among older adults. Programs aiming at preventing or slowing functional decline in old age should be sensitive to gender.