A Paradox Lost: Weight Was No Plus With Diabetes

Diabetes patients may gain no survival edge by being overweight contradicting obesity paradox

(RxWiki News) While some studies have shown that diabetes patients who are overweight may have a lower risk of dying (known as the “obesity paradox”), being bigger may not tip the scales in your favor.

Some investigations have suggested that diabetes patients who are heavy might live longer than those of normal weight. A new study, however, has refuted this so-called “obesity paradox.”

This new study showed that type 2 diabetes patients who were overweight or obese did not have improved survival compared to those who were not overweight.

"Maintain a healthy weight to help combat diabetes."

Frank Hu, MD, PhD, professor of nutrition and epidemiology at Harvard School of Public Health (HSPH), and his colleagues analyzed data on more than 10,000 patients with type 2 diabetes, looking for the relationship between body weight and mortality.

Drawing on information from 8,970 women from the Brigham and Women's Hospital-based Nurses' Health Study and 2,457 men in the Health Professionals Follow-up Study (HPFS), the researchers calculated the body mass index (BMI) of each patient shortly before the diagnosis of diabetes.

Normal BMI is regarded as a measure between 18.5 and 24.9, according to the National Heart, Lung, and Blood Institute. Overweight is 25 to 29.9, and obese is a BMI of 30 or greater.

Over an average follow-up period of almost 16 years, 3,083 deaths were reported in this study.

In comparison to those participants with a BMI of 22.5 to 24.9, those in the lowest BMI category for this study (18.5 to 22.4) had a 29 percent increased risk of death, and those in the highest BMI categories (30 to 34.9) had a 24 percent increased risk of death. The researchers observed no mortality benefit among those who were overweight or obese.

The authors of this study wrote that previous studies finding an “obesity paradox” may have been limited compared to this investigation. These limitations included smaller study populations and failure to take into account factors such as smoking and undiagnosed chronic diseases, which can lead to weight loss and contribute to premature death.

Deirdre Tobias, ScD, a research fellow in the Department of Nutrition at HSPH and an author of this study, said that these factors can skew the relationship between weight and mortality to make the normal weight participants seem worse off than the overweight and obese patients.

“As a result, people with higher BMIs might have artificially improved survival rates," she said in a press release.

Dr. Hu added in a statement, “These data dispel the notion that being overweight or obese confers survival advantage among diabetic patients. Clearly, weight management is an important therapeutic strategy for overweight or obese individuals with type 2 diabetes.”

"This study once again emphasizes the relationship between a normal BMI and healthy living," said Andre Hall, MD, an OBGYN at Birth and Women's Care, PA in Fayetteville, NC.

"The list of diseases and medical conditions that people expose themselves to are extensive when they fail to maintain a healthy weight. The so-called diabetes paradox has always been questioned by medical professionals in that it simply was not consistent with medical teachings that emphasize the importance of a normal weight when managing these conditions," Dr. Hall explained.

This study was published January 16 in the New England Journal of Medicine. The research was funded by the National Institutes of Health and the American Diabetes Association.

Review Date: 
January 15, 2014