Zolpidem use and hip fractures in older people

OBJECTIVES: The widespread use of sedative-hypnotics in older populations makes it imperative to identify hazardous regimens that should be avoided and safer regimens that may be used preferentially by older people. Although benzodiazepines have been shown to increase fall and fracture risk, zolpidem, a nonbenzodiazepine hypnotic, has been advocated as a safer alternative. DESIGN: Case-control study of hip fracture cases and controls in 1994. SETTING: All subjects were age 65 and older and enrolled in Medicare, and in Medicaid or the Pharmaceutical Assistance to the Aged and Disabled program of New Jersey. PARTICIPANTS: Cases (n = 1,222) were patients who underwent surgical repair of a hip fracture. They were frequency-matched to four controls (n = 4,888) based on age and gender. MEASUREMENTS: Use of sedative-hypnotics and other medications was assessed in the 180 days before the index event. We assessed other covariates, including demographic, clinical, and healthcare utilization variables in the prior 180 days. RESULTS: Zolpidem use was associated with a significant increased risk of hip fracture (adjusted odds ratio (AOR) 1.95; 95% confidence interval (Ci) = 1.09-3.51). Other psychotropic medication classes with significantly increased risks included benzodiazepines (AOR 1.46; 95% CI = 1.21-1.76), antipsychotic medications (AOR 1.61; 95% CI = 1.29-2.01), and antidepressants (AOR 1.46; 95% CI = 1.22-1.75). In subanalyses, preferential use of zolpidem by subjects at greater risk of hip fracture did not appear to explain the apparent risk of hip fracture with zolpidem use. CONCLUSION: Use of zolpidem by older people was associated with nearly twice the risk of hip fracture, even after controlling for possible demographic and clinical confounders. Rather than being a safer alternative, zolpidem may be associated with risks that are as great as those seen with conventional benzodiazepines in older patients.