MON-526 Risk of Cardiovascular (CV) Conditions in Patients with Chronic Hypoparathyroidism (HypoPT)

Abstract

Abstract Background: Chronic hypoparathyroidism (HypoPT) managed with conventional therapy (i.e., oral calcium and active vitamin D) may potentially increase the risk of cardiovascular (CV) conditions. This study evaluated whether chronic HypoPT is associated with increased risk of various CV conditions. Methods: A retrospective cohort study was conducted to compare the risk of CV conditions between chronic HypoPT patients (excluding those receiving parathyroid hormone) and randomly selected non-HypoPT patients over 5 years of follow-up using a large US commercial claims database (Q1 2007 - Q2 2017). CV conditions in this analysis included atrial fibrillation (AF), cerebrovascular disease, coronary artery disease (CAD), heart failure (HF), peripheral vascular disease (PVD), tachyarrhythmia, and a composite endpoint of related pathophysiology (i.e., cerebrovascular disease, CAD, HF, and PVD). The first date of follow-up (i.e., index date) for HypoPT patients was the earliest HypoPT diagnosis date at least 6 months after the initial HypoPT diagnosis and for non-HypoPT patients was the date of a randomly selected medical claim. Patient characteristics at baseline (the 6 months prior to index date) were compared between cohorts. Among those free of each CV condition at baseline, the risks of first occurrence of each condition during the study period were compared using Kaplan-Meier analysis and adjusted Cox proportional hazards models. Adjusting parameters included demographic (age, sex, race, region, and index year) and clinical (other comorbid CV conditions, chronic kidney disease, hypertension, and diabetes) characteristics at baseline. Results: A total of 8,097 HypoPT and 40,485 non-HypoPT patients were included. Overall, HypoPT patients were older (58.6 vs. 47.3 years), a higher proportion were female (76.2 vs. 54.4%), and a higher proportion had AF (6.0 vs. 2.7%), cerebrovascular disease (6.0 vs. 3.0%), CAD (9.6 vs. 5.3%), HF (5.9 vs. 2.4%), PVD (7.4 vs. 2.8%), and tachyarrhythmia (0.7 vs. 0.4%) at baseline. Kaplan-Meier analyses showed that HypoPT patients had increased risk of new occurrence of each CV condition and the composite CV endpoint compared to non-HypoPT patients (all p<0.001). The adjusted hazard ratios (HRs) associated with HypoPT vs. non-HypoPT were 1.70 (95% confidence interval [CI]: 1.48, 1.94) for AF, 1.47 (1.34, 1.61) for cerebrovascular disease, 1.42 (1.29, 1.57) for CAD, 1.63 (1.46, 1.83) for HF, 1.66 (1.51, 1.82) for PVD, 1.68 (1.32, 2.14) for tachyarrhythmia, and 1.64 (1.53, 1.76) for the composite CV endpoint. Conclusions: Chronic HypoPT was associated with significant increased risk of CV conditions. Further research is warranted to understand the potential mechanisms for the relationship of chronic HypoPT and its management with the observed risk. Funding: Shire