Post-transplantation management of hyperparathyroidism and its association with kidney graft survival and fibrosis

Abstract

Background: Hyperparathyroidism (HPT) is a potential risk factor for graft loss after kidney transplantation (KTx). However, the effects of HPT management on graft outcomes remain unclear. This retrospective study aimed to investigate the impact of HPT status and its management on graft outcomes. Methods: Patients who underwent KTx were categorized based on their HPT status and treatment at 1-year post-KTx into four groups: normal (no HPT), normocalcemic HPT, hypercalcemic HPT, or intervention (parathyroidectomy or calcimimetics within 1 year after KTx). Patients treated for HPT beyond the first year post-KTx were censored. The primary outcome was death-censored graft survival and the secondary outcome was the progression of interstitial fibrosis and tubular atrophy (IFTA) at 1-year post KTx. Results: Among 1264 patients, the 10-year death-censored graft-survival rate was lowest in the hypercalcemic HPT group (79.7%), whereas the intervention group had a survival rate of 100.0%. In the multivariate Cox regression analysis, hypercalcemic HPT was associated with an increased risk of graft loss (fully adjusted hazard ratio [HR] = 4.25, P = 0.001, compared to the normal group). Contrarily, the intervention group did not show an increased risk of graft loss (fully adjusted HR = 0.28, P = 0.239). Additionally, hypercalcemia during the first year after KTx was significantly associated with IFTA progression (fully adjusted odds ratio = 1.91, P = 0.038). Conclusion: Hypercalcemic HPT was associated with inferior graft survival and IFTA progression. Proactive management of HPT may reduce the risk of graft loss and mitigate IFTA progression.