The elimination half-life of benzodiazepines and fall risk: two prospective observational studies.

ABSTRACT. Background: the STOPP criteria advise against the use of long-acting benzodiazepines (LBs). Objective: to study whether LBs are associated with a higher fall risk than short-acting benzodiazepines (SBs) (elimination half-life ≤10 h). Methods: we used base-line data and prospective fall follow-up from the Longitudinal Aging Study Amsterdam, a longitudinal cohort study including 1,509 community-dwelling older persons (Study 1) and from a separate fall prevention study with 564 older persons after a fall (Study 2). Time to the first fall after inclusion and number of falls in the first year after inclusion were the primary endpoints. Results: both in Study 1 and Study 2 the use of SBs was associated with time to the first fall, hazard ratio (HR) 1.62 (95% CI: 1.03–2.56) and HR 1.64 (95% CI: 1.19–2.26),respectively. LBs were not significantly associated with time to first fall, HR 1.40 (0.85–2.31) and HR 1.08 (0.72–1.62). In both studies, the use of SBs was also associated with number of falls, odds ratio (OR) 1.28 (95% CI: 1.01–1.61) and OR 1.37 (95% CI: 1.10–1.70). LBs were not significantly associated with number of falls, OR 1.23 (0.96–1.57) and 1.10 (0.82–1.48). Conclusions: the use of SBs is not associated with a lower fall risk compared with LBs. The use of both SBs and LBs by old persons should be strongly discouraged.