NEW YORK (Reuters Health) – New research shows “alarming levels” of obesity in most ethnic groups in the United States, principal investigator Dr. Gregory L. Burke, of Wake Forest University, Winston-Salem, North Carolina told Reuters Health. The study also confirms the potentially deadly toll obesity exacts on the heart and blood vessels.

“The obesity epidemic has the potential to reduce further gains in U.S. life expectancy, largely through an effect on cardiovascular disease mortality (death),” Burke and colleagues warn in the latest issue of Archives of Internal Medicine.

Among 6,814 middle-age or older adults participating in the Multi-Ethnic Study of Atherosclerosis, or “MESA” study, researchers found that more than two thirds of white, African American and Hispanic participants were overweight and one third to one half were obese.

Obesity rates were far lower in Chinese Americans in the study, with 33 percent overweight and just 5 percent obese, suggesting, Burke said, that high rates of obesity should not considered “inevitable.”

The investigators also found that obese adults, compared with normal-weight adults, had higher rates of high blood pressure (up to more than twice as high), abnormal lipids (two- to three-fold higher), and diabetes, despite a “huge number” being on costly medications to lower blood pressure and lipid levels and control diabetes, Burke said.

“As the obesity numbers increase further, we will spend an even larger amount of health care dollars just treating risk factors,” Burke said.

Obese adults also had more silent vascular disease (blood vessel disease that causes no symptoms); they had more atherosclerosis (hardening of the arteries) and thicker heart walls, even after adjusting for “traditional” risk factors like high blood pressure and high cholesterol levels.

Given the higher amount of silent blood vessel disease with obesity, Burke said “one could worry that this will cause us to reverse our 50-year decline in cardiovascular disease mortality due to the obesity epidemic.” This will likely be accompanied by an increase in diabetes, other heart disease risk factors, and silent disease – “on top of the aging of the baby boom generation.”

“Our findings support the imperative to redouble our efforts to assist in increasing healthy behaviors and to remove…barriers to maintaining a healthy weight,” Burke and colleagues conclude.

SOURCE: Archives of Internal Medicine, May 12, 2008.