Diabetes, not obesity, raises severe health risk

Findings from a new study suggest that obesity per se is not a risk factor for organ failure or death. However, the risk is increased with diabetes, which often develops in people with a high body mass index (BMI).

"There are several studies out there showing worse outcomes for people with higher BMIs," study co-author Dr. David M. Mannino, from the University of Kentucky Medical Center in Lexington, told Reuters Health. "Surprisingly, most of the studies really didn't look at how diabetes entered into the picture."

Mannino's team investigated this in an analysis of data on 15,408 subjects who participated in a forward-looking population-based study, and report their findings in the medical journal Critical Care.

The participants' BMI and whether or not they had diabetes were determined at the start of the study. The main outcomes were the development of acute organ failure within 3 years of the initial evaluation, in-hospital death during organ failure, and death at 3 years in all subjects and in those with organ failure.

Consistent with previous research, the likelihood of having diabetes was higher in obese subjects. The rate of diabetes among subjects with a BMI of at least 30 (classified as obese) was 22 percent, significantly higher the 8 percent rate seen among subjects with a lower BMI.

As noted, BMI alone had no bearing on the risk of acute organ failure. Diabetes, by contrast, was associated with a higher rate of organ failure (2.4 percent) than was seen among people without diabetes (0.7 percent).

Among patients with organ failure, those with diabetes also had an elevated risk of death compared with nondiabetic patients, while hospitalized (46 percent vs. 12 percent) and at 3 years (51 percent vs. 21 percent).

Given the association between a high BMI and diabetes, obese people are still at elevated risk, albeit indirectly, for developing the adverse outcomes described in the present study, Mannino noted.

SOURCE: Critical Care, September 24, 2006.