(Ivanhoe Newswire) -- Women who are extremely obese may have greater health risks than previously thought. A new study reveals more of them have high blood pressure, diabetes and high cholesterol than women who aren't as obese.

Researchers at the University of Pittsburgh looked at data from 90,185 women from 40 centers in the United States and followed up for an average of seven years. They examined the link between weight and the risk of coronary heart disease (CHD) based on the degree of obesity. Obesity is usually measured as a body mass index of 30 or higher and has three sub-categories: obesity 1 (BMI 30-34.9), obesity 2 (BMI 35-39.9) and extreme obesity (BMI 40+).

Researchers say accounting for the degree of obesity is important in understanding the weight-related health risk. The study reveals overall, extremely obese women were more likely to die over the seven-year follow-up period than those in the other weight categories. The prevalence of extreme obesity varied with race and ethnicity from 1 percent among Asian and Pacific Islanders to 10 percent among black women.

"Calculating the weight-related risks of morbidity and mortality based on our findings in earlier population samples, which tended to reflect lower degrees of obesity, may underestimate the risks for diverse groups," the researchers write. "More accurately assessing weight-related health risk may both improve policy decisions about obesity and assist women in making informed decisions about their health."

Researchers found weight-related risk for all-cause mortality, coronary heart disease mortality, and coronary heart disease incidence did not differ by race or ethnicity. Until now it has been unclear whether health risks increase or plateau as body weight increases through the levels of obesity.
 

SOURCE: Journal of the American Medical Association, 2006;296:79-86