Risk of Hip Fracture in Benzodiazepine Users With and Without Alzheimer Disease

Abstract

Objectives: To investigate the association between benzodiazepine and related drug (BZDR) use and hip fracture as well as postfracture mortality and duration of hospital stay in community-dwellers with and without Alzheimer disease (AD).

Design: Retrospective cohort study.

Setting: The register-based Medication Use and Alzheimer's disease (MEDALZ) study, including all community-dwelling persons diagnosed with AD in Finland during 2005-2011 (n = 70,718) and their matched comparison persons without AD.

Participants: Persons without BZDR use during the year preceding the AD diagnosis or the corresponding matching date as well as persons without history of hip fracture were included in this study.

Measurements: We investigated the risk of hip fracture associated with BZDR use compared with nonuse separately in persons with and without AD. Further, we investigated the association between BZDR use during hip fracture and 1-year mortality as well as longer than a 4-month hospital stay after hip fracture. Associations were reported as hazard ratios and odds ratios with 95% confidence intervals (CI).

Results: BZDR use was associated with an increased risk of hip fracture in persons with and without AD (adjusted hazard ratio 1.4 [95% CI 1.2-1.7] and 1.6 [95% CI 1.3-1.9], respectively). BZDR use during hip fracture was associated with longer than 4-month postfracture hospital stay in persons with AD [adjusted odds ratio 1.9 (95% CI 1.3-2.8)] but not in comparison persons. One-year mortality was not associated with BZDR use during hip fracture.

Conclusions: Higher threshold in prescribing BZDRs for neuropsychiatric symptoms might decrease the hip fracture rate and affect the length of hospital stay in persons with AD.

Keywords: Alzheimer disease; benzodiazepines; drug safety; hip fracture; postfracture hospital care; prescription register.