PHILADELPHIA — The presence of central obesity in patients with type 2 diabetes did not modify the overall ACCORD Blood Pressure trial findings, according to results of an analysis presented by Joshua I. Barzilay, MD, of the Southeast Permanente Medical Group in Atlanta, Ga. Moreover, intensively lowering BP in centrally obese individuals adds to CVD protection, with the exception of stroke.
“We know, and this is pretty obvious to everyone, that obesity is increasing in the United States and the rate is going up and up, though lately maybe it has reached a plateau. Along with this, we know BP goes up. Looking at the majority of large randomized clinical studies in hypertension that have been done in the last … decade, we can see just about all of these studies have [patients with] a mean BMI of about 29 or 30. This suggests that most of the BP we’re seeing is in people who are overweight or on the border of obesity,” Barzilay said during the ADA Diabetes Care Symposium at the ADA’s 72nd Scientific Sessions.
To examine the relationship between central obesity and hypertension, and whether obese patients may benefit from aggressive BP lowering, Barzilay examined subanalyses of the ACCORD trial.
The ACCORD study, which finished several years ago, included about 10,000 patients who were randomly assigned to intensive glucose and nonintensive glucose arms.
One substudy of the ACCORD trial examined lipids and found that raising HDL and lowering triglycerides had an effect on CVD outcomes vs. no intervention, Barzilay said. In both groups, LDL was <100 mg/dL and there was no difference between the two arms. Another substudy looked at BP in about 4,700 randomized patients — half to treatment to achieve systolic BP <120 mm Hg and half to treatment to achieve systolic BP between 130 to 135 mm Hg.
The overall outcome of the BP study demonstrated no difference between the standard and intensive BP groups, according to Barzilay. In terms of the primary endpoint — nonfatal MI and nonfatal stroke, as well as CV death — the two treatments were equivalent. Only in stroke was there a significant difference; patients assigned intensive treatment did better than those who received standard therapy.
The study’s conclusion was that intensive BP treatment was effective at preventing stroke, with prevention contingent upon 5 years of intensive treatment in 89 people to prevent one incident.
“Are these outcomes the same if someone is centrally obese?” Barzilay asked. “Here’s the answer: If we go through we can see that the primary outcome is nonfatal MI, stroke and CVD death; the P [value] for interaction between the four quartiles of obesity does not reach statistical significance. In other words, the benefit achieved from intensive vs. nonintensive treatment was not different between the quartiles of obesity; of the people who are very centrally obese, there is no difference.”
Similarly for stroke, he said, the benefit of intensive vs. nonintensive treatment did not differ among the quartiles of central obesity, which were measured using waist-to-height ratio. When using just waist as a measurement of central obesity, the results were the same.
“If we looked at outcomes and adjusted for the degree of central obesity, once again the overall findings of the ACCORD Blood Pressure study remain the same. If you are treating BP intensively, you will prevent stroke, but not the other outcomes,” he said.
When Barzilay analyzed the association between central obesity and any of the ACCORD outcomes, there was no strong association between the primary outcome of stroke or nonfatal MI with the degree of central obesity, but CVD mortality was related to central obesity.
“The heavier you are, the greater your risk of CV death,” he said. – by Stacey L. Fisher
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- Dr. Barzilay reports no relevant financial disclosures.