Background: Kidney transplantation confers an increased risk for bone fractures. However, there is poor consensus on the incidence of fractures in kidney transplant recipients (KTRs), partly attributable to differences in the types of fractures studied. Additionally, the effects of bone disease on post-transplant outcomes are unknown. We assessed the incidence of all-site and major osteoporotic fractures (MOFs: vertebral, hip, forearm, and shoulder fractures) in KTRs and quantified the effect of MOFs on all-cause graft failure, death-censored graft failure, and death with graft function.

Methods: This single-center retrospective observational cohort study included 1121 KTRs transplanted between January 1, 2004 and December 31, 2013. Study follow-up terminated on June 30, 2014. Data on fractures and graft outcomes were obtained from patients' electronic records, including clinical notes and radiology reports. Survival analyses (Kaplan Meier and Cox proportional hazard models) were used to determine fracture incidence and compare graft/patient outcomes. Fractures were modeled as a time-varying exposure in models of time to graft loss or death.

Results: The cohort (mean age 50.8 ± 13.3 years; 61.4% male) had a median follow-up of 4.06 years (IQR: 2.14, 6.51). A total of 179 patients (15.9%) suffered at least one post-transplant fracture at any skeletal site, with a 10-year cumulative incidence of 30.7% (95% CI: 23.7, 39.1). MOFs occurred in 89 patients (7.9%), with a 10-year cumulative incidence of 17.2% (95% CI: 12.4, 23.7) corresponding to a moderate fracture risk categorization (10 to 20%). MOFs showed no significant association with the incidence of death-censored graft failure (HR 1.27 [95% CI: 0.58, 2.76]), total graft failure (HR 0.70 [95% CI: 0.36, 1.37]), or death (HR 0.27 [95% CI: 0.07, 1.10]).

Conclusions: KTRs are at moderate MOF risk. Our analyses showed a higher fracture incidence compared to other Canadian KTR cohorts, likely due to difference in the health status of patients selected for transplantation. Unadjusted analyses in this cohort showed no significant effect of post-transplant MOFs on graft outcomes. Analyses to adjust for potential confounders and corroborate radiologically diagnosed fractures with clinical notes to validate incident events are ongoing.

CITATION INFORMATION: Atagu N, Nguyen T, Phan N, Famure O, Li Y, Kim J. The Burden and Outcomes of Fractures in Kidney Transplant Recipients. Am J Transplant. 2016;16 (suppl 3).

« Back to 2016 American Transplant Congress