Doctor K: Diabetes study offers mixed results

DEAR DOCTOR K: I just heard on the radio that some study says that intensive diet and exercise don’t decrease heart disease risk in diabetics. Is this true?

DEAR READER: I assume ou’re referring to results from the recently publicized Look AHEAD (Action for Health in Diabetes) trial. The results of this study were reported in June.

Here’s what we know: Type 2 diabetes increases the risk of stroke and heart disease.

We also know that people who achieve a healthy weight and exercise regularly have a lower risk of stroke and heart disease. So you’d think that overweight people with Type 2 diabetes also would benefit from a program of intensive diet and exercise.

The study was a large, randomized trial of more than 5,000 overweight men and women with Type 2 diabetes. Half were assigned at random to lose weight and maintain their weight loss through intensive diet and exercise. The control group met three times a year for group counseling sessions to discuss lifestyle changes to control diabetes.

After almost 10 years, the rates of heart attacks, strokes and heart-related deaths were essentially the same in both groups. That result was a real downer. That is, until you read the study in detail.

For example, the people in the intensive-change group lost only slightly more weight than the control group: 4 percent versus 2.5 percent. So though the research team called it “intensive diet and exercise,” it did not do a lot to achieve the goal of weight loss. Another difference between groups is that the control group was taking more heart-healthy medicines. So any real benefits from the slightly better weight loss in the intensive-change group might have been canceled out by this difference in medicines.

Lifestyle changes did have some benefits in this study. People in the intensive-change group improved their blood sugar with fewer drugs, and they lowered their risk for other diabetes complications. Some patients with Type 2 diabetes who achieve a healthy weight and exercise regularly can control their blood sugar without needing medicines any longer.