Risk factors predicting severe hypocalcemia after total parathyroidectomy without autotransplantation in patients with secondary hyperparathyroidism

OBJECTIVE: This study was performed to investigate the risk factors for severe hypocalcemia (SH) after total parathyroidectomy without autotransplantation (TPTX) in patients with secondary hyperparathyroidism. METHODS: We retrospectively analyzed the records of 136 patients with secondary hyperparathyroidism treated by TPTX. The patients were categorized as having SH or non-SH based on their postoperative blood calcium concentration. The risk factors for SH were identified by comparing the clinical characteristics between the two groups and by performing multiple logistic regression analyses. RESULTS: After surgery, 46.0% of the patients had hypocalcemia and 31.7% had SH. Evidence of renal osteodystrophy on lumbar radiographs and the serum concentrations of intact parathyroid hormone (iPTH), calcium, and alkaline phosphatase (ALP) were different between the two groups. The SH group had higher preoperative iPTH and ALP concentrations than the non-SH group. In addition, more patients with SH showed renal osteodystrophy. Logistic regression analyses indicated that preoperative hypocalcemia and a high ALP concentration were independent predictors of SH. CONCLUSION: Preoperative hypocalcemia and a high ALP concentration were identified as risk factors for SH following TPTX.