Incident Fractures in Kidney Transplant Recipients: A Nationwide Cohort Study from South Korea

초록

Background An increased fracture incidence is a challenging issue in kidney transplant recipients (KTRs). This study investigated the incidence, location, and predictors of fractures after kidney transplantation (KT). Methods Data were obtained from the Korea Organ Transplantation Registry, which is a nationwide cohort study of KTRs. A total of 4,134 KTRs who underwent KT between January 2014 and June 2019 were included in the study. The cumulative inci-dence and risk factors for fractures were evaluated using the Kaplan-Meier method and Cox proportional hazard model. Results During a follow-up of 12,441.04 person-years (median, 2.94 years), 63 patients developed incident fractures. The cumulative 5-year incidence of fractures was 2.10%. The most frequent fracture locations were the leg (25.40%) and foot (22.22%). Older recipient age (hazard ratio [HR], 1.043; 95% confidence interval [CI], 1.016–1.070; P=0.002), diabetes mellitus (HR, 2.627;95% CI, 1.559–4.426; P<0.001) and previous KT (HR, 10.085; 95% CI, 1.679–60.554; P=0.029) at baseline were associated with a higher risk of fractures after KT, whereas the use of anti-thymocyte globulin as induction therapy (HR, 0.170; 95% CI, 0.053– 0.542; P=0.003) and a higher serum phosphorus at 6 months posttransplantation (HR, 0.537; 95% CI, 0.366–0.788; P=0.001) were associated with a lower risk of fractures. Conclusions The first 5 years after KT were associated with the risk of peripheral skeletal fractures. Recipient age, comorbid diabetes mellitus, induction strategy, previous KT history and serum phosphorus level may be responsible for the incidence of fractures.