Diabetics who delay treating hypertension have more strokes, heart attacks

Among people with diabetes who develop high blood pressure, those who delay getting it under control may be more likely to have heart attacks and strokes than their counterparts who manage it promptly, a recent study suggests.

Researchers examined data on 43,986 patients with diabetes who started treatment for high blood pressure between 2002 and 2007. People who waited until blood pressure was more elevated to start treatment were 10% more likely to have events like fatal heart attacks and strokes, the study found.

“Hypertension (high blood pressure) is a risk factor for atherosclerotic cardiovascular disease, which includes coronary artery disease, myocardial infarction (heart attack), and stroke. Diabetes is also a risk factor for the same clinical endpoints,” said Dr. Sridharan Raghavan, a researcher at the University of Colorado Anschutz Medical Campus and the Rocky Mountain Regional VA Medical Center.

“Lowering blood pressure in diabetes patients with hypertension can mitigate some of the risk of atherosclerotic cardiovascular disease,” Raghavan said by email.

As they do with other groups at high risk for cardiovascular disease, doctors recommend that diabetics consider treating blood pressure at a lower threshold than low-risk individuals would start at.

The American Heart Association and the American College of Cardiology recommend that people with diabetes start treatment for hypertension when the “top number” - the systolic blood pressure - is above 130 mmHg (millimeters of mercury). The goal is to bring systolic blood pressure below 130 mmHg.

The American Diabetes Association recommends that people with diabetes start treatment when systolic blood pressure exceeds 140 mmHg, with the goal of getting it below that number.

Results from the current study suggest that individuals with diabetes and hypertension who begin blood pressure lowering therapy when their systolic blood pressure exceeds 130 mmHg may have fewer deaths from heart attacks and strokes than diabetics who wait until blood pressure is higher to initiate treatment.

After an average follow-up period of more than nine years, many people in the study who achieved systolic blood pressure below 130 mmHg after two years of treatment also fared better than individuals whose blood pressure didn’t get that low.

But among people whose systolic blood pressure exceeded 140 mmHg when they started treatment, even if they got that number below 130 they still fared worse than patients who started out with systolic pressure below 130.

The study wasn’t a controlled experiment designed to prove whether or how the timing of blood pressure treatment directly impacts the risk of having or dying from events like heart attacks and strokes.

The results still underscore that even among diabetics, blood pressure management may not be one size fits all, said Dr. Costantino Iadecola, director and chair of the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine in New York City.

“In patients with diabetes, hypertension should be treated as quickly as possible if blood pressure starts to inch up above 130 mmHg,” Iadecola, who wasn’t involved in the study, said by email. “In patients with starting blood pressure greater than 140 mmHg, blood pressure should still be treated but not aggressively, so as not to reduce blood pressure excessively.”