Association Between Treatment of Secondary Hyperparathyroidism and Posttransplant Outcomes.

BACKGROUND Secondary hyperparathyroidism (SHPT) affects nearly all patients on maintenance dialysis therapy. SHPT treatment options have considerably evolved over the past 2 decades, but vary in degree of improvement in SHPT. Therefore, we hypothesize that the risks of adverse outcomes after kidney transplantation (KT) may differ by SHPT treatment. METHODS Using the SRTR and Medicare claims data, we identified 5,094 adults (age≥18) treated with cinacalcet or parathyroidectomy for SHPT prior to receiving KT between 2007-2016. We quantified the association between SHPT treatment and delayed graft function and acute rejection using adjusted logistic models and tertiary hyperparathyroidism (THPT), graft failure, and death using adjusted Cox proportional hazards; we tested whether these associations differed by patient characteristics. RESULTS Of 5094 KT recipients who were treated for SHPT while on dialysis, 228 (4.5%) underwent parathyroidectomy and 4866 (95.5%) received cinacalcet. There was no association between treatment of SHPT and posttransplant delayed graft function, graft failure or death. However, compared to patients treated with cinacalcet, those treated with parathyroidectomy had a lower risk of developing THPT (aHR=0.56, 95%CI: 0.35-0.89) post-KT. Furthermore, this risk differed by dialysis vintage (pinteraction=0.039). Among patients on maintenance dialysis therapy for ≥3 years prior to KT (n=3,477, 68.3%), the risk of developing THPT was lower when treated with parathyroidectomy (aHR=0.43, 95%CI: 0.24-0.79). CONCLUSIONS Parathyroidectomy should be considered as treatment for SHPT, especially in KT candidates on maintenance dialysis for ≥3 years. Additionally, patients treated with cinacalcet for SHPT should undergo close surveillance for development of tertiary hyperparathyroidism post-KT.