Compared with the muscle relaxant tizanidine, the use of baclofen in older adults is associated with a significantly increased risk of falls, researchers report. “The risk of fracture was comparable among the older users of baclofen, tizanidine, and cyclobenzaprine,” the authors conclude. “Our findings may inform risk-benefit considerations in the increasingly common clinical encounters where oral muscle relaxants are prescribed.”
The new-user, active-comparator study included older adults who were newly treated with baclofen, tizanidine, or cyclobenzaprine at Geisinger Health in 2005–18. Based on propensity score-based inverse probability of treatment weighting (IPTW), the authors found: “The study cohort comprised … 2,205 new baclofen users, 1,103 new tizanidine users, and 9,708 new cyclobenzaprine users. During a median follow-up of 100 days, baclofen was associated with a higher risk of fall compared to tizanidine (IPTW incidence rate, 108.4 vs. 61.9 per 1,000 person-years; subdistribution hazard ratio [SHR], 1.68 [95% CI, 1.20–2.36]). The risk of fall associated with baclofen was comparable to cyclobenzaprine (SHR, 1.17 [95% CI, 0.93–1.47]) with a median follow-up of 106 days. The risk of fracture was similar among patients treated with baclofen versus tizanidine (SHR, 0.85 [95% CI, 0.63–1.14]) or cyclobenzaprine (SHR, 0.85 [95% CI, 0.67–1.07]).”