Construction and validation of a risk prediction model for early hungry bone syndrome in maintenance hemodialysis patients post-parathyroidectomy.

Objectives: Parathyroidectomy (PTX) is an effective treatment for refractory secondary hyperparathyroidism (SHPT), but it can lead to hungry bone syndrome (HBS), significantly threatening the health of maintenance haemodialysis (MHD) patients. While previous studies have analyzed the risk factors for HBS post-PTX, the predictive performance and clinical applicability of these risk models need further validation. This study aims to construct and validate a risk prediction model for HBS in MHD patients with SHPT post-PTX.

Methods: A retrospective analysis was conducted on 368 MHD patients with SHPT who underwent PTX at Changsha Jieao Nephrology Hospital from January 2020 to December 2021. Patients were divided into a HBS group and a non-HBS group based on the occurrence of HBS. General data, surgical information, and biochemical indicators were compared between the 2 groups. Multivariate logistic regression was used to identify factors influencing HBS, and a risk prediction model was established. The model's performance was evaluated using receiver operator characteristic (ROC) curves, decision curves, and calibration curves. External validation was performed on 170 MHD patients with SHPT who underwent PTX at the Third Xiangya Hospital of Central South University from January to December 2022.

Results: The incidence of HBS post-PTX in MHD patients with SHPT was 60.60%. Logistic regression analysis identified preoperative bone involvement (OR=3.908, 95% CI 2.179 to 7.171), preoperative serum calcium (OR=7.174, 95% CI 2.291 to 24.015), preoperative intact parathyroid hormone (iPTH) (OR=1.001, 95% CI 1.001 to 1.001), preoperative alkaline phosphatase (ALP) (OR=1.001, 95% CI 1.000 to 1.001), and serum calcium on the first postoperative day (OR=0.006, 95% CI 0.001 to 0.038) as independent risk factors for HBS (all P<0.01). The constructed risk prediction model demonstrated good predictive performance in both internal and external validation cohorts. The internal validation cohort showed an accuracy of 0.821, sensitivity of 0.890, specificity of 0.776, Youden index of 0.666, and area under the curve (AUC) of 0.882 (95% CI 0.845 to 0.919). The external validation cohort showed an accuracy of 0.800, sensitivity of 0.806, specificity of 0.799, Youden index of 0.605, and AUC of 0.863 (95% CI 0.795 to 0.932).

Conclusions: Preoperative bone involvement, serum calcium, iPTH, ALP, and serum calcium on the first postoperative day are influencing factors for HBS in MHD patients with SHPT post-PTX. The constructed risk prediction model based on these factors is reliable.