Associations of Concurrent Hypertension and Type 2 Diabetes with Mortality Outcomes: A Prospective Study of US Adults

Objective: To investigate associations of concurrent hypertension and type 2 diabetes(T2D) with mortality in US 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(NHANES). Participants were categorized into 4 mutually exclusive categories: 1) no hypertension and no T2D, 2) hypertension only, 3) T2D only, and 4) co-existing 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 between1999-2018 from 6% to 12%. Overall, 50.5% did not have T2D or hypertension, 38.4% had hypertension only, 2.4% had T2D only, and 8.7% had both. During a 9.2y median follow-up, 7,734 deaths occurred. Concurrent hypertension and T2D vs. no hypertension or T2D predicted higher all-cause(HR(95%CI):2.46(2.45-2.47)) and cardiovascular mortality risk(HR(95%CI):2.97(2.94-3.00)), with stronger associations in females vs. males(p-interaction<0.01). Compared to having hypertension or T2D only, concurrent hypertension and T2D predicted up to 66% and >2-fold higher all-cause and cardiovascular mortality risk, respectively, and associations varied by sex, race, and ethnicity (p-interaction<0.01) depending on the referent group (T2D only or hypertension only). Concurrent prediabetes and elevated blood pressure predicted up to 19% higher mortality risk compared to 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 US.