Association Between Psychotropic Medication Polypharmacy and an Objective Measure of Balance Impairment Among Middle-Aged Adults: Results from the US National Health and Nutrition Examination Survey.

OBJECTIVE: Psychotropic medications (e.g., antidepressants, anxiolytics, and neuroleptics) are increasingly prescribed with two or more taken concurrently (polypharmacy), and have been associated with an increased risk of falling. The aim of this study was to examine the association between psychotropic medication use and balance impairment using an objective balance measure.

METHODS: We derived data from participants aged 40 years and older in the US National Health and Nutrition Examination Survey (1999/00-2003/04) who completed the Modified Clinical Trial of Sensory Interaction and Balance and indicated current medications (n = 3090). Balance impairment was defined as failing the Modified Clinical Trial of Sensory Interaction and Balance condition 4 (standing on foam surface, eyes closed). Medication use included specific psychotropic classes, a count of psychotropic medications, and a count of non-psychotropic medications taken concurrently. Nested multiple logistic regression assessed relationships between medication use and balance impairment, adjusting for covariates and complex sampling.

RESULTS: One third of participants had balance impairment. After accounting for medical comorbidities, there was no relationship between individual classes of psychotropic medications and balance impairment. After adjusting for all covariates, there was a dose-response relationship between the number of psychotropic medications taken and balance impairment, with every additional medication associated with a 35% higher odds (odds ratio = 1.35; 95% confidence interval 1.07-1.70). In comparison, there was no increase in the odds of balance impairment associated with each additional medication taken for participants only taking non-psychotropic medications.

CONCLUSIONS: Psychotropic medication polypharmacy is associated with an increased odds of balance impairment. Clinicians should exercise caution when prescribing combinations of psychotropic medications, and refer to physical therapy for assessment and treatment if balance impairment is detected.