The good news: A new study shows that not all overweight people have heart disease risk factors.
The bad news: These individuals can still develop risk factors for heart and other diseases.
“Generally, we need to recognize that people and their metabolisms are different, and that those differences can be important,” says Greg Nichols, PhD, senior investigator and diabetes researcher with the Kaiser Permanente Center for Health Research in Portland.
“People with diabetes are much more likely to be obese or overweight, although not all overweight and obese people develop diabetes,” Nichols adds. “Diabetes puts people at higher risk for heart disease, stroke, blindness, kidney problems, amputations and several other health problems.”
Nichols says smaller studies have been done that looked at a similar premise, but none that could do so on the scale of his study, which focused on adults who are overweight and obese, but who did not have diabetes.
The study used the Patient Outcomes Research to Advance Learning, a consortium of four health care delivery systems — Kaiser Permanente (Colorado, Georgia, Hawaii, Mid-Atlantic States, Northern California, Northwest, and Southern California), Group-Health Cooperative (Washington State), HealthPartners (Minnesota), and Denver Health — and their 10 research centers.
“This study also gave us the ability to look at classes of obesity, which hadn’t been done before,” Nichols says.
Among the 1.3 million in the study, 14 percent had normal blood sugar, cholesterol and blood pressure readings, Nichols reports.
“This means they did not develop the same heart disease risk factors that most overweight and obese people develop,” he says. “We are not sure why this is the case. It does not necessarily mean that these people are healthy. They may go on to develop these risk factors as they get older, and they are also more likely than people of normal weight to develop kidney disease and die earlier.”
The Kaiser study included patients who were enrolled in one of nine integrated health systems, and had been enrolled for at least one year, starting in January 2012.
“We conducted the study by examining the patients’ electronic medical record,” Nichols says. “Patients had to have recorded weight and height records to be included in the study.”
The results were that among 47.5 percent of participants with obesity, 9.6 percent had none; among participants with morbid obesity, 5.8 percent had none. Age was strongly associated with cardiometabolic risk factors (elevated blood pressure, elevated triglycerides, low HDL cholesterol and prediabetes) in multivariable analysis.
According to the study, more than two-thirds of U.S. adults have a body mass index that indicates overweight or obesity, and although obesity is a major risk factor for type 2 diabetes, the condition does not develop in many individuals with excess weight.
The study also shows that risks climb with age, body mass index increases, and the number of risk factors a person has. Compared with non-Hispanic white adults, Hispanic, Asian and Hawaiian/Pacific Islander adults were significantly more likely to have at least one cardiometabolic risk factor, and non-Hispanic black adults were 28 percent less likely.
According to the study, the person with obesity who has no cardiometabolic abnormalities is considered to have “metabolically healthy obesity,” but that doesn’t mean they are out of the woods. Regardless of metabolic abnormalities, people still run the risk of chronic kidney disease and other problems.
Nichols says people who are overweight or obese and don’t have risk factors should still be vigilant about taking care of their health and trying to achieve a healthy weight.
“Just because they don’t have heart disease risk factors now doesn’t mean they won’t develop these risk factors in the future,” he says. “Losing weight is probably the best way to control diabetes, and in some cases losing weight can reverse the disease.”
Other strategies include eating healthy foods, increasing fruit and vegetable intake, reducing fat intake, exercising and possibly controlling diabetes through medication if a person can’t lose weight, Nichols says.
“Almost all of us can benefit from more exercise,” he adds. “It doesn’t have to be terribly strenuous to improve your risk factors, and you’ll feel better, too.”
The study was published in the March 9 issue of “Preventing Chronic Disease,” the official journal of the Centers for Disease Control and Prevention, and can be viewed at cdc.gov by clicking on the links to the magazine article.
For more information, call Media Information Manager Mary Sawyers at 503-320-1966 or send an email, Mary.A.Sawyers@kpchr.org.