Benzodiazepine Initiation and the Risk of Falls or Fall-Related Injuries in Older Adults Following Acute Ischemic Stroke.

Abstract

Background and objectives: Benzodiazepine (BZD) use in older adults after acute ischemic stroke (AIS) is common. We aimed to assess the risk of falls or fall-related injuries (FRIs) in older adults after the use of BZDs during the acute poststroke recovery period.

Methods: We emulated a hypothetical randomized trial of BZD use during the acute poststroke recovery period using linked data from the Get With the Guidelines Stroke Registry and Mass General Brigham's electronic health records. Our cohort included patients aged 65 years and older with an AIS admission between 2014 and 2021, no documented previous stroke, and no BZD prescriptions in the 3 months before admission. The potential for immortal time and confounding bias was addressed separately using inverse probability weighting.

Results: We analyzed data from 495 patients who initiated inpatient BZDs within 3 days of admission and 2,564 who did not. After standardization, the estimate was 694 events per 1,000 (95% CI 676-709) for the BZD initiation strategy and 584 events per 1,000 (95% CI 575-595) for the noninitiation strategy. Subgroup analyses showed risk differences of 142 events per 1,000 (95% CI 111-165) and 85 events per 1,000 (95% CI 64-107) for patients aged 65-74 years and 75 years and older, respectively. Risk differences were 187 events per 1,000 (95% CI 159-206) for patients with minor (NIH Stroke Severity Scale score $\le$ 4) AIS and 32 events per 1,000 (95% CI 10-58) for those with moderate-to-severe AIS.

Discussion: Initiating BZDs within 3 days of an AIS is associated with an elevated ten-day risk of falls or FRIs, particularly for patients aged 65-74 years and for those with mild stroke. This underscores the need for caution when initiating BZDs, especially among individuals likely to be ambulatory during the acute and subacute poststroke period.