Abstract 4365060: Rising Mortality at the Crossroads of Endocrine and Cardiovascular Disease: National Trends in Hyperthyroidism and Hypertension (1999–2020)

Background: Hyperthyroidism and hypertension are interrelated endocrine and cardiovascular disorders associated with significant morbidity and risk of complications. Despite their clinical overlap, national mortality trends involving both conditions are underexplored. Understanding these patterns is essential to guide targeted prevention and management strategies across demographic and geographic populations. Objective: To examine U.S. mortality trends related to coexisting hyperthyroidism and hypertensive diseases from 1999 to 2020, focusing on differences by age, sex, race, region, and urbanization. Methods: This retrospective study analyzed U.S. death certificate data from the CDC WONDER database (1999–2020). Adults aged ≥25 years with hyperthyroidism (ICD-10: E05) and hypertensive diseases (ICD-10: I10–I15) listed as underlying causes of death were included. Age-adjusted mortality rates (AAMRs) per 100,000 population were calculated. Joinpoint regression was used to estimate annual percent change (APC) and average annual percent change (AAPC). Results: From 1999 to 2020, 13,440 deaths were attributed to hyperthyroidism and hypertensive diseases. The AAMR rose from 0.12 to 0.38, with an overall AAPC of 4.43% (95% CI: 0.42–8.60; p = 0.03). Women accounted for 10,201 deaths and had a higher AAMR than men (0.36 vs. 0.15). Among women, mortality increased significantly, especially from 2018–2020 (APC = 14.78%; p = 0.008), with an overall AAPC of 5.11% (95% CI: 3.57–6.68; p < 0.000001). Men experienced a steady increase (AAPC = 2.46%; p = 0.0005). Non-Hispanic White adults had the highest death count (n = 10,189) and a significant upward trend (AAPC = 5.22%; p = 0.0003). The South recorded the most deaths (n = 4,419), while the West had the highest AAMR (0.35) and a significant increase (AAPC = 4.39%; p = 0.03). Adults aged ≥65 years accounted for most deaths (n = 11,431), with an increasing trend (AAPC = 4.19%; p = 0.012). Although urban areas had more deaths (n = 10,673), rural areas saw a consistent and significant rise (AAPC = 2.82%; p < 0.00001). Conclusion: Mortality related to coexisting hyperthyroidism and hypertension increased significantly over the past two decades, especially among women, older adults, Non-Hispanic Whites, residents of the West, and rural populations. These findings highlight the need for targeted public health interventions to address emerging disparities in endocrine and cardiovascular comorbidity outcomes.