Association between antidepressants and falls in Parkinson's disease

Parkinson's disease (PD) patients have an increased risk of falls resulting in important social and economical consequences. Risk factors for falls include the use of psychotropic drugs, which are used for the treatment of PD neuropsychiatric symptoms. We aimed to determine the association between psychotropic drug use and falls in a PD cohort. A cross-sectional study from the NPF QII study UF site was conducted. Subjects reported presence and frequency of falls in the prior year. Frequency was scored from 0 (no falls) to 4 (falling daily). Antidepressants, antipsychotics, cognitive enhancers/stimulants, and benzodiazepines were considered psychotropics. Forty percent of the 647 subjects included had a fall in the previous year. Fallers were found to have clinical signs of a more advanced disease. After adjusting for confounding variables, the regression analysis showed that use of antidepressants alone (adjusted OR 2.2, CI 95 % 1.3-3.8, p = 0.04), benzodiazepines alone (adjusted OR 2.0, CI 95 % 1.1-3.5, p = 0.02), and the combination of antidepressants with benzodiazepines (adjusted OR 4.1, CI 95 % 2.0-8.3, p < 0.0001) were independently associated with the presence of falls. When comparing to those not on psychotropics, subjects on antidepressants alone had a significantly higher mean frequency of falls score (1.07 vs. 0.44, p < 0.0001). The use of antidepressants was independently associated with falls in our PD cohort after considering for confounding variables such as age and measures of disease progression. Other factors related to disease progression should be considered before claiming the use of psychotropic drugs as causative.