Sometimes getting the opposite of what you expected is still a good thing. This is especially true with the results of a new study that examined whether weight loss and exercise would reduce heart attacks and strokes in overweight and obese type 2 diabetes patients.
“We have not been able to show that trying hard to lose weight and getting more exercise has measurable effects on reducing heart attacks and strokes,” says Professor Robert Jeffery of the School of Public Health. While these surprising results disappointed the researchers, they may have also revealed something new regarding the prevention and treatment of cardiovascular disease.
The Look AHEAD (Action for Health in Diabetes) study was commissioned by the NIH as a 12-year, randomized study that followed more than 5,000 overweight or obese adults aged 45-76 with type 2 diabetes. The study was partially inspired by earlier research of pre-diabetics that examined if increased weight loss and exercise could pull them back from the brink and reverse the diagnosis. The previous research showed lifestyle changes could dramatically turn the tide and return as many as 50 percent of pre-diabetics to good health. The impressive results suggested that lifestyle changes would almost certainly reduce the risk of heart attacks and strokes in type 2 diabetes subjects.
To find out, the School of Public Health took part in Look AHEAD and locally recruited approximately 330 diabetics to participate in the study. The participants were divided into two treatment groups: The “lifestyle” group was coached weekly for six months on weight loss and increasing exercise and asked to log its activity and food intake. The “comparison” group was educated a few times year on managing diabetes through nutrition, physical activity and social support.
Between the two groups, the lifestyle contingent fared much better. The results showed the lifestyle group experienced greater weight loss, 6 percent, compared to the education group’s 3.5 percent. The lifestyle group also benefited from lower incidences of kidney disease, retinopathy, depression, lower blood glucose levels and higher levels of physical fitness and reported quality of life. The risk factors for cardiovascular disease improved for the lifestyle group, too, with lower blood pressures and higher “good” HDL cholesterol.
Curiously, both groups showed the same levels of “bad” LDL cholesterol. Researchers suspect this effect could be from the greater use of cholesterol-lowering drugs in the education group, which allowed them to match the reductions of their lifestyle counterparts.
Still, despite all of the lifestyle group’s improvements and gains over the comparison group, their risk of developing or dying from cardiovascular disease was the same: one percent. Shockingly, the group that worked up a sweat and lost more weight suffered just as many heart attacks and strokes as the group that was simply counseled on managing its diabetes.
How could it be that the group that followed the proven heart-healthy approach didn’t do a better job of avoiding cardiovascular disease? The answer could be in the participants’ medical history.
“Approximately one-third of participants had a stroke or heart attack before entering the study,” says Jeffery. “There may be a difference in the effectiveness of weight loss and exercise in people who haven’t had heart disease compared to those who have already had it.”
Nevertheless, the results of the study showed there are plenty of health benefits for diabetics who lose weight and exercise more. Jeffery said the results of the study won’t change recommending the course of action for type 2 diabetes patients. It’s just that maybe lifestyle changes are better at preventing cardiovascular disease than they are at treating it.
“The study proved what should be true not to be, and that’s equally as valuable to know,” says Jeffery.