Long-Term Risk of Hip Fracture After Ischemic Stroke

Abstract

Background and Purpose: Data are lacking on the long-term risk of hip fracture among patients with ischemic stroke. A better understanding of the contemporary incidence of hip fracture after ischemic stroke could benefit patient care by promoting strategies to prevent this disabling complication in stroke survivors. Methods: We performed a retrospective cohort study using inpatient and outpatient claims between 2008 and 2015 from a nationally representative 5% sample of Medicare beneficiaries. We included patients ≥66 years of age who were hospitalized with acute ischemic stroke, defined through a validated diagnostic code algorithm. We excluded patients who had a prior or concurrent hip fracture diagnosis at the time of ischemic stroke. The primary outcome was hip fracture requiring hospitalization. Survival statistics were used to calculate crude incidence rates, and the Kaplan-Meier method was used to calculate cumulative rates. Results: Among the 1 772 550 beneficiaries in our sample, 60 099 were diagnosed with an acute ischemic stroke without prior or concomitant hip fracture. During 4.5 (±2.2) years of follow-up, the incidence of hip fracture was 1.6 (95% confidence interval [CI]: 1.5-1.6) per 100 person-years in patients with acute ischemic stroke versus 0.6 (95% CI: 0.6-0.6) per 100 person-years in patients without acute ischemic stroke. The cumulative 5-year rate of hip fracture was 7.6% (95% CI: 7.2%-8.0%) among patients with acute ischemic stroke versus 2.8% (95% CI: 2.8%-2.9%) among the remaining Medicare beneficiaries. Conclusion: We found that among elderly Medicare beneficiaries with acute ischemic stroke, nearly 1 in 12 developed a hip fracture over the next 5 years.