Associations of Concurrent Hypertension and Type 2 Diabetes With Mortality Outcomes: A Prospective Study of U.S. Adults

OBJECTIVE: To investigate associations of concurrent hypertension and type 2 diabetes (T2D) with mortality in U.S. adults and elucidate differences by sex, race, and ethnicity. RESEARCH DESIGN AND METHODS: The study population included 48,727 adults from the 1999-2018 National Health and Nutrition Examination Surveys. Participants were categorized into four mutually exclusive categories: 1) no hypertension and no T2D, 2) hypertension only, 3) T2D only, and 4) coexisting hypertension and T2D. Outcomes were all-cause and cardiovascular mortality defined using ICD-10 codes. Kaplan-Meier curves and multivariable Cox proportional hazards models were used to evaluate associations of hypertension and T2D status with mortality risk. RESULTS: The burden of concurrent hypertension and T2D doubled between 1999 and 2018 from 6% to 12%. Overall, 50.5% of participants did not have T2D or hypertension, 38.4% had hypertension only, 2.4% had T2D only, and 8.7% had both. During a 9.2-year median follow-up, 7,734 deaths occurred. Concurrent hypertension and T2D versus no hypertension or T2D predicted higher all-cause (hazard ratio 2.46 [95% CI 2.45, 2.47]) and cardiovascular mortality risk (2.97 [2.94, 3.00]), with stronger associations in females versus males (P for interaction <0.01). Compared with having hypertension or T2D only, concurrent hypertension and T2D predicted up to 66% and more than twofold higher all-cause and cardiovascular mortality risk, respectively, and associations varied by sex and race and ethnicity (P for interaction <0.01), depending on the reference group (T2D only or hypertension only). Concurrent prediabetes and elevated blood pressure predicted up to 19% higher mortality risk compared with having neither or either condition. CONCLUSIONS: Concurrent hypertension and T2D predict high mortality risk, underscoring the critical need for contextual interventions that extend healthspan in the U.S.