Comorbid hypertension, diabetes up CVD, death risks

The dual presence of hypertension and diabetes in an individual puts them at increased risks of cardiovascular disease (CVD) and all-cause mortality beyond those associated with either condition alone, reveals a study.

A total of 967 deaths and 1,535 CVD events were recorded over a 7-year follow-up. 

Individuals with hypertension alone (adjusted hazard ratio [aHR], 1.571, 95 percent confidence interval [CI], 1.316–1.875; p<0.001), diabetes alone (aHR, 1.618, 95 percent CI, 1.187–2.205; p<0.01), and comorbid hypertension and diabetes (aHR, 2.041, 95 percent CI, 1.557–2.677; p<0.001) had greater risks of all-cause mortality than those without either condition.

Likewise, individuals with hypertension alone (aHR, 1.408, 95 percent CI, 1.233–1.608; p<0.001), diabetes alone (aHR, 1.036, 95 percent CI, 0.808–1.327; p>0.05), and both conditions (aHR, 2.011, 95 percent CI, 1.651–2.449; p<0.001) had elevated risks of CVD events.

Notably, patients with comorbid hypertension and diabetes had CVD risk that exceeded the sum of the risks due to hypertension or diabetes alone (relative excess risk ratio, 0.567, 95 percent CI, 0.136–0.999).

"The synergistic interaction between hypertension and diabetes aggravated the risk of CVD,” the investigators said. 

The study included 9,681 individuals without pre-existing CVD from the China Health and Retirement Longitudinal Study. The investigators classified participants into the following groups: hypertension alone, diabetes alone, both conditions, neither condition. They estimated the risks of CVD and all-cause mortality using multivariate Cox proportional hazards models.