Hungry Bone Syndrome after Parathyroidectomy Is Associated with Better Outcomes in ESKD

Background: Hyperparathyroidism (HPT) is common in patients with end-stage kidney disease (ESKD). Parathyroidectomy (PTX) is still necessary for patients who do not respond adequately to medications. Hungry bone syndrome (HBS) frequently occurs after PTX. Beyond lower recurrence rates of HPT, the long-term outcomes associated with HBS are largely unexplored. Methods: In this retrospective single-center study conducted between 2012 and 2022, 322 PTX were identified in 314 patients with ESKD. HBS was defined as serum albumin-corrected Ca levels <8.5 mg/dL occuring between 5-30 days post-PTX. The study evaluated baseline biochemical factors associated with HBS and examined adverse events, as well as changes in blood pressure, hematologic, and nutritional parameters 3-12 months after PTX, stratified by HBS status. Results: HBS was observed in 207 cases (64%). Male sex, lower serum Ca and higher PTH levels, and lack of active vitamin D treatment at baseline were independent predictors of HBS. Adverse events were similar between the HBS and no-HBS groups. Between group comparisons revealed HBS group experienced a more significant reduction in pulse pressure after surgery. There was a greater increase in Hb and serum Cr in the HBS group. The number of cases with Hb <11 g/dL and Cr/BSA <380 mg/m2 post-PTX was lower in the HBS group. Serum albumin levels increased significantly in both groups, with no significant difference between them. HBS was associated with a more substantial reduction in serum Ca and PO4 but not PTH levels, from baseline. At the end of the follow-up period, serum Ca levels remained lower in the HBS group, while serum PO4 and PTH levels were comparable between the two groups. Conclusion: In conclusion, HBS was associated with a more substantial improvment in blood pressure, anemia and muscle mass in ESKD patients.