SAT-750 Risk of chronic complications in thyroid cancer patients with postoperative hypoparathyroidism: A nationwide cohort study in Korea using the common data model

Abstract Disclosure: S. Hong: None. S. Ahn: None. C. Jung: None. Y. Cho: None. D. Seo: None. S. Kim: None. J. Yoo: None. Background: Chronic hypoparathyroidism (hypoPT) is associated with a range of complications, including renal, skeletal, neuropsychiatric, and cardiovascular issues. However, the risk of these complications in thyroid cancer patients with postoperative hypoparathyroidism (PO-hypoPT) has not been specifically studied. This study aimed to evaluate the risk of known chronic hypoPT-associated complications in thyroid cancer patients with PO-hypoPT compared to those with preserved parathyroid function after thyroidectomy. Methods: This retrospective observational cohort study utilized the nationwide claims database provided by the Health Insurance Review and Assessment Service of South Korea, encoded in the Observational Medical Outcomes Partnership Common Data Model (OMOP-CDM). Among 217,156 thyroid cancer patients aged 18 years or older who underwent thyroidectomy between January 2013 and December 2020, after 1:2 propensity score (PS) matching, 15,592 patients with PO-hypoPT and 27,906 patients with preserved parathyroid function were analyzed. Outcomes included nephrolithiasis, renal insufficiency, major adverse cardiac events (MACE), seizures, infections, cataracts, and depression. Large-scale PS matching accounted for age, sex, year and month of cohort entry, and comprehensive medical histories (including conditions, medications, procedures, and measurements). Cox proportional hazards regression analysis was conducted to estimate hazard ratios (HRs) for complications. Results: The median follow-up duration for both groups was approximately 5.0 years. Thyroid cancer patients with PO-hypoPT had a significantly higher risk of nephrolithiasis (HR 1.17, 95% CI 1.04-1.30), renal insufficiency (HR 1.75, 95% CI 1.50-2.03), and MACE (HR 1.10, 95% CI 1.01-1.19) compared to those with preserved parathyroid function. However, the risks of other complications, including seizures, infections, cataracts, and depression, were not significantly different between the two groups. Conclusion: Thyroid cancer patients with PO-hypoPT face an increased risk of nephrolithiasis, renal insufficiency, and MACE compared to those with preserved parathyroid function. These findings emphasize the importance of close monitoring of renal function and cardiovascular health during the long-term follow-up of thyroid cancer patients with PO-hypoPT. Presentation: Saturday, July 12, 2025