Abstract
BACKGROUND: Although many studies have implicated antidepressants as a risk factor for falls, it is not clear if risk accrues with duration of use or if there are acute risks associated with initiation of the prescription. We conducted a case-crossover study of nursing home residents with a fall to determine the effect of an antidepressant change (defined as the new prescription of an antidepressant or increasing the dose of a previously used antidepressant) on fall risk. METHODS: Among 1,181 nursing home fallers, we compared the frequency of antidepressant changes during the hazard period (1-7 days before the fall) with the frequency of antidepressant changes during the control period (8-14 days before the fall). Odds ratios were estimated using conditional logistic regression models. Results were estimated for non-selective serotonin reuptake inhibitors (SSRI) and SSRI prescriptions, separately. RESULTS: Mean age was 88 years, and 71% were females. Seventy participants experienced an antidepressant change during the hazard and/or control periods. The maximum effect of falling occurred within 2 days of a non-SSRI change (odds ratio: 4.7, 95% confidence interval, 1.3-16.2). The effect on falling was no longer significant at 5 days (odds ratio: 1.9, 95% confidence interval, 0.9-4.0). No association was found between SSRI changes and falls. CONCLUSIONS: Nursing home residents are at high risk of falls during the days following a new prescription or increased dose of a non-SSRI antidepressant. Increased surveillance should occur, particularly during the first 48 hours, in an effort to decrease falls.