New research indicates that obesity is a far greater problem for people with disabilities than previously thought.

Nearly 42 percent of American adults with disabilities are obese and 9 percent are extremely obese, according to a study being published in the July issue of the American Journal of Preventative Medicine.

In comparison, about 29 percent of adults without disabilities were found to be obese and 3.9 percent were identified as extremely obese, the study found.

The research is believed to be the first to examine weight issues among Americans with disabilities using actual measurements of height and weight from the individuals studied rather than anecdotal reports alone.

“Prior to this research, national samples only indicated obesity prevalence in adults with disabilities at 29 to 31 percent,” said Katherine Froehlich-Grobe, an associate professor of health promotion and behavioral science at The University of Texas School of Public Health, Dallas Regional Campus and the study’s lead author. “We were surprised at the magnitude of how high obesity prevalence was among those with a disability.”

For the study, Froehlich-Grobe and her colleagues looked at data from the National Health and Nutrition Examination Survey, a routine federal data collection that includes information from physical examinations and interviews with Americans about their health and nutrition status. The researchers compared obesity rates and health information from more than 11,500 adults with disabilities to that of over 20,000 people without disabilities whose experiences were documented in the survey.

In addition to higher obesity rates, people with disabilities had greater incidence of chronic illnesses like diabetes, hypertension and high cholesterol and were twice as likely to take lipid-lowering drugs and prescription medication for high blood pressure, the study found.

Froehlich-Grobe said the findings highlight the need for physicians and national obesity-prevention efforts to do more to help people with disabilities manage their weight.