Predicting Hungry Bone Syndrome: Risk Stratification After Parathyroidectomy in CKD-Related Hyperparathyroidism

Background: Hungry bone syndrome (HBS) is a frequent and potentially severe complication following parathyroidectomy in patients with chronic kidney disease (CKD) and secondary (SHPT) or tertiary hyperparathyroidism (THPT). We aimed to identify preoperative risk factors associated with the development of HBS in this population. Methods: We conducted a retrospective cohort study including 99 adult patients with CKD-associated SHPT or THPT who underwent parathyroidectomy at Hospital San Vicente Fundación between 2018 and 2024. HBS was defined as corrected serum calcium <8.5 mg/dL requiring intravenous calcium supplementation for at least 72 h postoperatively. Clinical, biochemical, and histopathological variables were evaluated. Multivariable logistic regression analysis was performed to identify independent predictors of HBS, and model discrimination was assessed using the area under the receiver operating characteristic curve (AUC). Results: Overall, 40.4% of patients developed HBS after parathyroidectomy. Compared with patients without HBS, those with HBS more frequently had preoperative musculoskeletal symptoms (82.5% vs. 32.2%), higher preoperative intact parathyroid hormone levels (2135 vs. 1561 pg/mL), and parathyroid adenoma on histology (57.5% vs. 25.4%). In multivariable analysis, preoperative musculoskeletal symptoms (OR 10.92; 95% CI 2.32–51.43) and parathyroid adenoma (OR 6.16; 95% CI 1.38–27.54) were independently associated with increased risk of HBS. Conversely, higher preoperative calcium levels (OR 0.36; 95% CI 0.16–0.85) and the use of calcitriol or vitamin D receptor activators (OR 0.24; 95% CI 0.07–0.81) were protective factors. The final model demonstrated good discrimination (AUC = 0.86; 95% CI 0.77–0.93). Conclusions: HBS is a common complication after parathyroidectomy in patients with CKD-associated SHPT or THPT. Preoperative musculoskeletal symptoms and parathyroid adenoma were associated with increased risk, whereas higher calcium levels and calcitriol/vitamin D receptor activator use appeared protective. Early identification of high-risk patients may facilitate perioperative risk stratification and targeted management strategies.