SBP reduction lowers risk of diabetic CAD, nephropathy

Lowering systolic blood pressure (SBP) leads to a reduced risk of diabetic coronary artery disease (CAD) and nephropathy, results of a study have shown.

“It provides genetic evidence for the beneficial effect of lifelong SBP control in preventing diabetes-related vascular outcomes,” the investigators said.

Two-sample Mendelian randomization (MR) was used to assess the causal effect of decreasing SBP on the risk of macrovascular and microvascular outcomes in diabetic patients. Some 362 SBP-related genetic variants from a large genome-wide association study (n=299,024) and the UK Biobank (n=375,25) were used as exposure.

The investigators examined five macrovascular and microvascular complications in 60,742 cases as outcomes in diabetes, including CAD, peripheral artery disease (PAD), nephropathy, retinopathy, and composite complications. All cases were diagnosed along with diabetes.

Finally, follow-up analyses were done by conducting seven sensitivity analyses and comparing the present MR with results in general population, and clinical trials.

Genetic predisposition of each 10-mm Hg reduction in SBP significantly correlated with a 28-percent decrease in CAD risk (odds ratio [OR], 0.71, 95 percent confidence interval [CI], 0.59‒0.89; p=0.002), a 34-percent drop in nephropathy risk (OR, 0.66, 95 percent CI, 0.54‒0.81; p<0.001), and a 34-percent reduction in the risk of composite complications (OR, 0.66, 95 percent CI, 0.58‒0.76; p<0.001).

Such SBP control was also nominally associated with decreased risks of PAD (OR, 0.69, 95 percent CI, 0.48‒0.99) and retinopathy (OR, 0.90, 95 percent CI, 0.81‒0.99).

In addition, the MR results in diabetes were comparable with those in the general population and clinical trials.