Burden of diagnosed diabetes increased between 1988-1994, 2005-2006

NHANES data show that 13% of adults have diabetes; 40% of them have not been diagnosed.

More than 40% of people aged 20 years and older have hyperglycemic conditions with prevalence rates higher in minorities, according to results of NHANES 2005-2006. While diagnosed diabetes has increased, other conditions have remained relatively unchanged.

“We’re facing a diabetes epidemic that shows no signs of abating, judging from the number of individuals with pre-diabetes,” Catherine Cowie, PhD, director of the Diabetes Epidemiology Program, National Institute of Diabetes and Digestive and Kidney Diseases, said in a press release.

Cowie and colleagues examined the prevalence of diagnosed diabetes, undiagnosed diabetes and pre-diabetes in the United States from 2005-2006. They used fasting and 2-hour glucose tolerance test values and compared the prevalence rates between those from 2005-2006 with those from 1988-1994.

In 2005-2006, NHANES included a probability sample of people aged ≥12 years (n=7,267) and participants were classified by glycemic status.

Prevalence increased

These more recent findings showed that the crude prevalence of total diabetes in people aged ≥20 years was 12.9% and approximately 40% of those people were undiagnosed, according to the study. In people aged ≥20 years, the crude prevalence of impaired fasting glucose was 25.7% and impaired glucose tolerance was 13.8%, and almost 30% had either. Results of the study also showed that nearly one-third of people aged ≥65 years had diabetes and three-quarters had diabetes or pre-diabetes.

When compared with non Hispanic whites, age- and sex-standardized prevalence of diagnosed diabetes was approximately twice as high in non Hispanic blacks (P<.0001) and Mexican Americans (P=.0001), according to the study. Undiagnosed diabetes was not higher.

In people aged ≥20 years, crude prevalence of diagnosed diabetes increased from 5.1% during 1988-1994 to 7.7% during 2005-2006 (P=.0001). Prevalence of undiagnosed diabetes and pre-diabetes was stable, although the proportion of undiagnosed total diabetes decreased in Mexican Americans, according to the study.

“The 2005-2006 NHANES is the first national survey in 15 years to include the oral glucose tolerance test; the addition of the OGGT gives us greater confidence that we are seeing the true burden of diabetes and pre-diabetes in a representative sample of the U.S. population,” Cowie said.

Cowie and colleagues suggested that lifestyle modifications such as weight management and increased physical activity should be urged in patients with diabetes and pre-diabetes. – by Christen Haigh

Diabetes Care. 2009;32:287-294.