Effects of central nervous system polypharmacy on falls liability in community-dwelling elderly.

ABSTRACT

BACKGROUND: While central nervous system (CNS) active medications such as psychotropics and narcotic analgesics have been implicated in contributing to falls in older adults, the combined effect of multiple CNS-active medications has not been investigated. The purpose of this study was to examine the influence, in community-dwelling elderly, of (1) taking multiple CNS-active medications on fall liability and (2) individual classes of CNS-active medications (using discrete drug classification) on the risk of falls after controlling for important confounders--age, mobility, cognition and depression. METHODS: 305 community-dwelling male veterans (age 70-104) were screened at study entry for mobility, cognition and depression. CNS-active medications were categorized as benzodiazepines, other sedative-hypnotics, neuroleptics, tricyclic antidepressants, and opioid analgesics. Subjects were prospectively followed for 6 months to monitor falls; at the end of this time period, subjects were classified as fallers (at least one fall) or nonfallers. The relationship between CNS-active drug use and falls was examined using multivariable analyses. RESULTS: The risk of falls was significantly greater in CNS-active medication users as compared with nonusers. Adjusted odds ratio for one CNS-active drug was 1.54 (95% confidence interval 1.07-2.22) and for two or more agents 2.37 (95% confidence interval 1.14-4.94). CONCLUSIONS: In community-dwelling elderly, the use of multiple CNS-active medications is associated with enhanced falls liability, over and above the use of one CNS-active drug alone. This apparent dose-response relationship provides support for causality.