Concurrent Hypertension, Type 2 Diabetes Linked to Higher Mortality Risk

Concurrent hypertension and type 2 diabetes significantly increase mortality risk, according to a study published in Diabetes Care, highlighting the need for targeted interventions to extend the healthspan of individuals in the US.¹

The researchers explained that hypertension and type 2 diabetes are consistently among the leading contributors to morbidity and cardiovascular mortality, both in the US and globally.² Although previous studies have shown that each condition independently increases the risk of all-cause and cardiovascular mortality, the impact of coexisting hypertension and type 2 diabetes on these outcomes has not been examined in a nationally representative sample of US adults.¹

To address this gap, they analyzed the relationship between concurrent hypertension and type 2 diabetes and the risk of all-cause and cardiovascular mortality among US adults. The researchers also evaluated and quantified the mortality risk associated with coexisting prediabetes and elevated blood pressure.

Concurrent hypertension and type 2 diabetes significantly increase mortality risk, emphasizing the need for targeted health interventions to improve outcomes. | Image Credit: greenapple78 - stock.adobe.com

“Understanding the contribution of having multiple cardiometabolic morbidities to mortality risk in the US population is key for informing individual and population-level interventions aimed at addressing the chronic disease burden, compressing morbidity, and extending the lifespan while preserving quality of life,” the authors wrote.

The study population consisted of eligible adult participants from the National Health and Nutrition Examination Survey (1999-2018), a representative sample of the civilian, noninstitutionalized US population. Therefore, the researchers analyzed 48,727 individuals. Participants were categorized into 4 mutually exclusive categories: individuals with neither condition, individuals with hypertension only, individuals with type 2 diabetes only, and individuals with both conditions.

The researchers generated Kaplan-Meier curves and used Cox proportional hazards regression models to estimate HRs and 95% CIs for the associations between hypertension and type 2 diabetes status and both all-cause and cardiovascular mortality. Participant mortality status was determined using the National Death Index through December 31, 2019, and cardiovascular mortality was defined according to the International Classification of Diseases, 10th Revision, Clinical Modification codes.

Among the study population, the mean age was 47 years, and the majority were female (52%) and non-Hispanic White (69%). Overall, 50.5% of the population had neither condition, 38.4% had hypertension alone, 8.7% had both conditions, and 2.4% had type 2 diabetes alone.

Over a median follow-up of 9.2 years, there were 7734 deaths, including 2013 cardiovascular-related deaths. Mortality rates varied by condition, as 31% of participants with concurrent type 2 diabetes and hypertension died during follow-up, compared with 22% of those with hypertension only, 20% of those with type 2 diabetes only, and 6% of those with neither condition.

Therefore, participants with concurrent hypertension and type 2 diabetes had more than twice the risk of all-cause mortality (HR, 2.46; 95% CI, 2.45-2.47) and nearly 3 times the risk of cardiovascular mortality (HR, 2.97; 95% CI, 2.94-3.00) than those who had neither condition.

Meanwhile, having only hypertension was associated with a 48% increased risk of all-cause mortality and a 93% increased risk of cardiovascular mortality. In contrast, participants with type 2 diabetes alone had an 82% higher risk of all-cause mortality and a 25% higher risk of cardiovascular mortality.

Regarding the secondary objective, participants with both elevated blood pressure and prediabetes had a 19% higher risk of all-cause mortality compared with those with elevated blood pressure alone. Similarly, those with both conditions had a 13% higher risk of cardiovascular mortality than those with prediabetes alone.

Lastly, the researchers acknowledged their limitations, including the lack of longitudinal data on changes in hypertension, type 2 diabetes status, control, and medication use during the follow-up period. This prevented them from assessing how changes in glycemic and blood pressure control and self-management over time might influence mortality risk. Consequently, they recommended areas for further research to build upon their findings.

“Future longitudinal studies are needed to elucidate associations of multiple cardiometabolic morbidities and changes in BP [blood pressure] and glycemic control across the life course with further morbidity and all-cause and cause-specific mortality,” the authors concluded.

References

1. Yuan Y, Isasi CR, Al-Rousan T, et al. Associations of concurrent hypertension and type 2 diabetes with mortality outcomes: a prospective study of US adults. Diabetes Care. doi:10.2337/dca24-0118
2. Martin SS, Aday AW, Almarzooq ZI, et al. 2024 heart disease and stroke statistics: a report of US and global data from the American Heart Association. Circulation. 2024;149(8):e347-e913. doi:10.1161/CIR.0000000000001209