M. Joyner1, M. Schwab2, A. Gillis3, J. Fazendin3, B. Lindeman3, H. Chen3, P. Zmijewski3 1University of Tennessee at Knoxville, Knoxville, TN, USA 2Albany Medical Center, General Surgery, Albany, NY, USA 3University Of Alabama at Birmingham, Endocrine Surgery, Birmingham, Alabama, USA
Introduction: Timing of parathyroidectomy in secondary hyperparathyroidism (SHPT) in the context of planned renal transplantation is controversial. Recent guidelines published in 2022 by the American Association of Endocrine Surgeons cite a lack of quality evidence in this realm. The fragility index (FI) is a statistical measure indicating the minimum number of patients whose status would need to change from event to non-event for the results to lose statistical significance. Here, we calculate the FI of literature assessing transplant outcomes and their relationship to timing of parathyroidectomy (PTX) for SHPT.
Methods: A comprehensive search strategy was performed in several academic databases for articles on adult populations with key words including renal/kidney transplant, secondary hyperparathyroidism, parathyroidectomy, and outcomes. Case reports, systematic reviews, database studies, and noninferiority studies were excluded. Results were required to include data that allowed us to perform a fragility calculation. Abstracts were screened by two independent reviewers with conflicts resolved by a third. An FI of 8 or greater was considered a high-quality study.
Results: Two thousand and six studies were extracted and 147 met criteria for full text review. Of these, only 21 studies included necessary data to calculate an FI. Studies with more than one outcome of interest were given multiple FIs. Only three studies had a FI of 8, 8, and 9 (strong evidence), four studies had indexes of 1-3 (weak evidence), and nineteen indexes were 0 (no statistical significance). High-quality (FI 8-9) findings included two studies that found that patients with persistent hyperparathyroidism had more graft dysfunction/failure. Another high- quality finding demonstrated that patients with PTX after renal transplantation had more renal dysfunction than those without PTX.
Conclusion: Of 147 studies, only three met criteria for strong levels of evidence based on FI ³8. These studies demonstrated that persistent HPT post-transplant may worsen graft function and failure, and that PTX post-transplant has negative effects on transplantation outcomes. These data, therefore, suggest that PTX should be performed prior to renal transplant to optimize outcomes.