Senior physician, clinical professor Center for Clincial Research and Prevention, Frederiksberg & Bispebjerg Hospitals Bispebjerg and Frederiksberg Hospitals Frederiksberg, Denmark
Background: Worldwide, approximately 171 million fall accidents occur every year. Although falls typically result from a complex interaction of predisposing and precipitating risk factors, the use of sedative-hypnotic medication is often singled out as a prominent risk factor.
Objectives: To evaluate the risk of falls and fractures in adults treated with benzodiazepines, Z-drugs, or melatonin.
Methods: The source population included 699,335 persons aged 15 years and older with a first-time purchase of benzodiazepines, Z-drugs, or melatonin registered in the Danish National Prescription Registry between 2003 and 2016. For this population we registered incident falls and fractures in the Danish National Patient Registry between 2000 and 2018. Associations were examined in a self-controlled case-series analysis, and conditional Poisson regression was used to derive incidence rate ratios (IRR) of the risk of falls and fractures during six predefined periods.
Results: Of the source population, 62 105 persons (8.7%) and 36 808 (5.2 %) were registered with respectively a fall or fracture during any of the six periods. The IRR of falls was higher among older adults (≥70 years) compared to younger adults ( < 40 years). For older adults, compared to the baseline (>1 year before initiation), the risk of falls was highest during the 3 months before initiation (pre-treatment period, IRRmen+70 =4.22, (95% CI 3.53-5.05), IRRwomen+70= 3.03, (95% CI 2.59-3.55) followed by the 3 months after treatment initiation (treatment period): IRRmen+70= 2.96 (95% CI 2.41-3.65), IRRwomen+70 1.72 (95%CI 1.43-2.06). The risk continued to be slightly higher in the later treatment periods. Contrarily, in men and women aged 40-69 years, the risk was only higher in the 3-month pre-treatment period. The incidence of falls among young men and women seemed even slightly lower after initiation of sedating medication (treatment period, IRRmen15-39 =0.66, 95% CI 0.50-0.86), IRRwomen15-39= 0.65, 95%CI 0.51-0.83). When examining fractures, the IRR of fractures was similarly highest in older men and women during the pre-treatment period (pre-treatment period, IRR men+70= 6.64, 95% CI 5.31-8.30, IRRwomen+70= 4.65, 95% CI 3.86-5.60) and decreased during treatment. The similar risks were also slightly higher in adults aged 40-69 years, but not in young adults.
Conclusions: Although falls and fractures occur more often in persons treated with sedative-hypnotic medication, the higher risk of falls and fractures in the pre-treatment period relative to the period directly after treatment, suggests that this association is better explained by other factors that elicited the prescription of this medication rather than the adverse effects of the sedative-hypnotic medication.
