Considerable uncertainty prevails regarding risk factors for recurrent fracture among older patients with hip fracture. We aimed to investigate the relationship between prefracture stroke history, baseline mobility, and the risk of recurrent hip fracture. This cohort study was based on the Danish Multidisciplinary Hip Fracture Registry, 2011–2018 (n = 48,230). We estimated cumulative incidence (competing risk of death) of recurrent hip fracture and major osteoporotic fractures within 1 and 2 years comparing patients with/without prefracture stroke history. Analyses were performed overall and stratified on baseline mobility status (good mobility: Cumulated Ambulation Score ≥ 5 versus poor mobility: Cumulated Ambulation Score < 5). Using Cox regression, adjusted cause-specific hazard ratios (HRs) with 95% confidence intervals (CIs) were obtained. The 1-year cumulative incidence was 4.6% (95% CI: 3.9–5.4) among patients with stroke history and 4.3% (95% CI: 4.1–4.5) among patients without stroke history. For patients with good mobility, the cumulative incidence of recurrent hip fracture was 5.8% (95% CI: 4.3–7.5) versus 3.7% (95% CI: 3.4–4.0) for patients with versus without stroke history. Corresponding numbers for patients with poor mobility were 4.4% (95% CI: 3.6–5.5) and 5.0% (95% CI: 4.7–5.3). Stroke history was associated with an adjusted HR of 1.55 (95% CI: 1.15–2.10) for recurrent fracture among patients with good mobility. In contrast, no association was observed among patients with poor mobility (adjusted HR 0.88 [95% CI: 0.70–1.10]). The associations were attenuated after 2 years of follow-up and for major osteoporotic fractures. In conclusion, stroke history was associated with slightly higher risk of recurrent fracture among patients with first-time hip fracture in the overall analysis, although the CI included a null result. The association was modified by baseline mobility: Patients with stroke history and good mobility had a markedly higher risk, whereas patients with stroke and poor mobility did not.
Keywords:
FRACTURE PREVENTION; GENERAL POPULATION STUDIES; HIP FRACTURE; OSTEOPOROSIS; STROKE