Polypharmacy and Gait Performance in Community–dwelling Older Adults

Objectives: To examine the relationship between polypharmacy and gait performance during simple (normal walk (NW)) and complex (walking while talking (WWT)) locomotion. Design: Cross-sectional. Setting: Community. Participants: Community-dwelling older adults (N = 482). Measurements: Polypharmacy, defined as use of five or more medications and a cohort-specific alternate definition of eight or more medications, was examined. Velocity (cm/s) measured quantitatively during NW and WWT conditions. Results: The 164 participants (34%) with polypharmacy of five or more medications were older (77.0 ± 6.6 vs 76.0 ± 6.4) and more likely to have hypertension, congestive heart failure, diabetes mellitus, myocardial infarction, and higher body mass index (BMI) and to have fallen within the last year than the remaining 318 without polypharmacy and walked 6 cm/s slower (P =.004) during NW and 4 cm/s slower during WWT (P =.07), adjusting for age, sex, and education. Group differences were not statistically significant after adjusting for comorbidities. Prevalence of polypharmacy of eight or more medications was 10%. This group walked 11 cm/s slower during NW (P <.001) and 8.6 cm/s slower during WWT (P =.01) than those without polypharmacy, adjusted for age, sex, and education. Participants taking eight or more medications had slower NW (8.5 cm/s; P =.01), and WWT (6.9 cm/s; P =.07), compared to those without polypharmacy, adjusting for comorbidities. Adjustments for BMI, high-risk drugs, falls, and comorbidities yielded slower NW (9.4 cm/s, P =.005) and WWT (7.9 cm/s, P =.04 among those with polypharmacy compared to those without polypharmacy). Conclusion: These results suggest an association between polypharmacy and locomotion that medical comorbidities only partly explained.