Long-term continuous use of benzodiazepines by older adults in Quebec: prevalence, incidence and risk factors.

Abstract

To determine the prevalence and incidence of long-term use of benzodiazepines and to assess patient-, prescriber-, and drug-related risk factors. Cohort study. 1,423 community-dwelling older adults in Quebec who participated in the Canadian Study of Health and Aging (CSHA1). Patient characteristics were obtained from the CSHA1 database. These were linked to provincial health insurance data to ascertain benzodiazepine use and prescriber characteristics. Use of benzodiazepines for at least 135 of the first 180 days following initiation of use. Twelve-month prevalence of long-term continuous use, standardized by age and gender to the Quebec population, was 19.8%. Twelve-month cumulative incidence of long-term continuous use was 1.9%. Older patients were more likely to proceed to long-term continuous use. Risk of long-term continuous use of benzodiazepines seems to increase with age. This association was found to be independent of gender, health status, anxiety, cognitive status, benzodiazepine type, and physician characteristics.