Fall-Risk-Increasing Drugs and Gait Performance in Community-Dwelling Older Adults: Exploratory Results from the Gait and Brain Study.

Abstract

While several psychotropic and cardiovascular drugs have been identified as fall-risk-increasing drugs (FRIDs) in older adults, the intervening mechanisms linking FRIDs and falls are unclear. It is plausible that gait performance is an intermediate variable on the causal pathway between FRIDs and falls. The current evidence on the relationship between medication use and gait performance in older adults is scarce. We aimed to assess the association between FRIDs and gait performance in community-dwelling older adults. This was a cross-sectional analysis using data from the Gait and Brain Study, a study of community-dwelling older adults aged 65years old and over (N=345). The following drug classes were assessed: antidepressants, benzodiazepines, alpha-blockers, beta-blockers, vasodilators, diuretics, statins and aspirin. Medication use was ascertained through validated questionnaires and electronic medical records. Multiple linear regression models were used to assess the association between each of the drug classes and gait speed and gait variability. Gait variability was expressed as the coefficient of variation (CV=mean/standard deviation) of stride time. Models were adjusted for age, sex, education, body mass index (BMI), mini-mental status exam (MMSE) score, Geriatric Depression Scale (GDS) score, general activity level, use of other FRIDs and comorbidity propensity score. Diuretic use was associated with significantly reduced gait speed (B=-7.97cm/s, 95% CI: -13.94, -2.00, P=0.009). Statin use was associated with significantly increased stride time CV (B=0.13, 95% CI: 0.02, 0.24, P=0.026). Other drugs did not have a statistically significant relationship with gait speed or variability. The association between diuretic use and reduced gait speed is consistent with existing evidence on diuretic use and increased fall risk. The association between statins and increased stride time variability is notable given inconclusive evidence in previous studies. Our results provide initial estimates of the association between FRIDs and gait performance in older adults for future longitudinal studies.