Use of Antidepressant Medications and Risk of Fracture in Older Women

Susan J. Diem, Terri L. Blackwell, Katie L. Stone, Jane A. Cauley, Teresa A. Hillier, Elizabeth M. Haney, Kristine E. Ensrud, for the Study of Osteoporotic Fractures Research Group

Use of antidepressant medications has been associated with increased risk of fracture, but prior studies have been limited by incomplete control of confounders or a limited number of fractures. Use of antidepressant medications by 8,217 community-dwelling women aged 69 and older from a population-based prospective cohort study at four US clinical centers was assessed by interview at four examinations over a 10-year period, beginning in 1992-1994. Use was coded as a time-dependent variable. Incident fractures occurring after the initial medication assessment until July 2007 were confirmed by radiographic reports. Potential confounders were included in multivariable models and updated at each follow-up visit. Compared to nonusers of antidepressant medications, women using SSRIs experienced a higher risk of nonspine fracture in age-adjusted models (HR = 1.36, 95% CI 1.11-1.67) and in multivariable models controlling for potential confounders (HR = 1.30, 95% CI 1.04-1.62). SSRI use was not associated with an increased risk of first hip fracture (HR = 1.01, 95% CI 0.71-1.44) but was associated with an increased risk of wrist fracture (HR = 1.54, 95% CI 1.01-2.36). TCA use was associated with an increased risk of nonspine fracture in age-adjusted models, but in multivariable models this risk was attenuated. SSRI use was associated with a higher risk of any nonspine fracture, but not hip fracture, in this cohort of older women. TCA use was associated with a higher risk of nonspine fracture, but this association was in part explained by confounding factors.