Increased risk of stroke in the year after a hip fracture: a population-based follow-up study.

BACKGROUND AND PURPOSE Stroke is a documented risk factor for hip fracture. However, no documented studies are available on the risk of stroke among patients with hip fracture. This study investigated the frequency and risk of stroke after hip fracture using a nationwide population-based study. METHODS The study cohort included 2101 patients hospitalized with a principal diagnosis of hip fracture from 2001 to 2004. The comparison cohort consisted of 6303 randomly selected subjects matched on sex, age, and year of index healthcare use as controls. We tracked patients for a 1-year period from their index healthcare encounter to identify those who had a stroke. Stratified Cox proportional hazard regression was performed to evaluate the association of hip fracture with subsequent stroke during 1-year follow-up. RESULTS Of a total of 8404 patients, 86 (4.1%) from the study group and 170 (2.7%) from the comparison group had strokes during the follow-up period (P<0.001). The stratified Cox proportional analysis shows that the 1-year crude hazard of stroke among patients with hip fracture was 1.55 times (95% CI, 1.19 to 2.03; P=0.001) that of the comparison group. Furthermore, after adjusting for the major cardiovascular risk factors, the increased stroke risk of patients with hip fracture persisted at about the same level as in the unadjusted analysis (hazard ratio, 1.53; 95% CI, 1.17 to 2.01; P=0.002). CONCLUSIONS Hip fracture is associated with increased risk of stroke in the next year.