Sex-specific relationship between vascular calcification and incident fracture in patients with end-stage renal disease

Background: Vascular calcification (VC) is a major component of mineral bone disorders in patients with end-stage renal disease (ESRD). Bone metabolism is affected by various factors, including sex hormones. This study investigated whether there was a sex-specific relationship between VC and incident fracture in patients with ESRD. Methods: This was a retrospective cohort study of dialysis patients from a single center. VC was assessed by the aortic calcification index (ACI) using abdominal computed tomography. Patients were grouped by sex and stratified into low or high ACI groups, according to the median ACI value. The association between ACI and incident fracture was analyzed. Results: Data from 593 patients (male: n = 328, median ACI, 14.57; female: n = 265, median ACI, 19.44) were included. During a median follow-up of 36.7 months, 71 patients (12.0%) developed fractures. The fracturefree survival rate was significantly lower in the high ACI group versus the low ACI group, both in males (P = 0.021) and females (P = 0.001). In males, multivariate analysis showed that the high ACI group and ACI per se were not significant risks for fracture. However, in females, both the high ACI group (adjusted hazard ratio, 2.720; P = 0.003) and ACI per se (adjusted hazard ratio, 1.768; P = 0.035) were independently associated with fracture after adjustment for confounding variables. Conclusion: VC was independently associated with incident fracture in female patients with ESRD. There may be a sex-specific relationship between VC and fracture in patients with ESRD.