Study: Obesity a Major Factor in the Diabetes Epidemic

April 2006 - More and more Americans are being diagnosed with diabetes. Is this rise in cases due to better testing, a change in diagnostic criteria, a true rise in incidence, or some combination of these and other factors?

In a study in the May issue of the American Journal of Preventive Medicine, researchers from the Centers for Disease Control and Prevention examine some of the reasons for this increase. They conclude that obesity is a major factor in this recent increase of newly diagnosed diabetes. Lifestyle interventions that reduce or prevent the prevalence of obesity among persons at risk for diabetes are needed to halt the increasing incidence of this disease.

Data from the 19972003 National Health Interview Survey (NHIS) of the National Center for Health Statistics, Centers for Disease Control and Prevention, were used to perform the analyses. Each year, approximately 31,000 people between the ages of 18 and 79 were asked whether a health professional had ever told them they had diabetes (excluding gestational diabetes in pregnant women). Annually, about 2000 people reported a diagnosis of diabetes.

Writing in the article, Linda S. Geiss states, "Among U.S. adults aged 1879 years, the incidence of diagnosed diabetes increased 41% from 1997 to 2003. During this period of rapid change, incidence increased at a greater rate among obese people, resulting in obesity being more prevalent among incident cases at the end of the time period than at the beginning.Altogether, these data suggest that obesity is a large factor -- although not the sole factor -- in the increasing incidence of diagnosed diabetes."

To determine if improved diabetes detection might be inflating the true incidence, the authors looked at the health status of 19971998 incident cases compared to the health status of 20022003 incident cases. No significant differences were found in the prevalence of hypertension, coronary heart disease, stroke, or poor or fair health status. From 1997 to 2003, when diabetes incidence increased by 41%, incident cases did not become remarkably healthier or younger, which one might have expected if the increased incidence were largely the product of improved diabetes detection.

The authors conclude, "Between 1997 and 2003, the incidence of diagnosed diabetes among U.S. adults increased at a rapid rate. This increase was not accompanied by large improvements in the health status of incident cases. The presented data suggest that obesity is a major factor in increasing incidence and that incident cases of diabetes are becoming more obese. Recent clinical trials have found that lifestyle changes that include moderate weight loss and exercise can prevent or delay the onset of diabetes among high-risk adults. The development and delivery of lifestyle interventions to people at risk for diabetes are needed to halt the increasing incidence of diabetes."

The article is "Changes in Incidence of Diabetes in U.S. Adults, 19972003" by Linda S. Geiss, MA, Liping Pan, MD, MPH, Betsy Cadwell, MSPH, Edward W. Gregg, PhD, Stephanie M. Benjamin, PhD and Michael M. Engelgau, MD, MPH. It appears in the American Journal of Preventive Medicine, Volume 30, Issue 5 (May 2006).

Source: American Journal of Preventive Medicine