Diabetes prevalence remains high in U.S. adults

The estimated prevalence of diabetes among U.S. adults ranged between 12% and 14% in 2011-2012, according to a recent study.

Researchers used data from the National Health and Nutrition Examination Surveys (NHANES) in 1988-1994 and 1999-2012, with 2,781 adults in 2011-2012 to estimate recent prevalence and 23,264 adults from 2010 to estimate trends. The authors defined diabetes as a previous diabetes diagnosis or as the following:

• an HbA1c level 6.5% or higher or a fasting plasma glucose (FPG) level of 126 mg/dL or higher (≥7 mmol/L) (HbA1c or FPG definition) or
• 1 of the previous criteria plus a 2-hour plasma glucose level of 200 mg/dL or higher (≥11.1 mmol/L) (HbA1c, FPG, or 2-hour plasma glucose definition).

Prediabetes was defined as an HbA1c level of 5.7% to 6.4%, a fasting plasma glucose level of 100 mg/dL to 125 mg/dL (5.6 mmol/L to 6.9 mmol/L), or a 2-hour plasma glucose level of 140 mg/dL to 199 mg/dL (7.8 mmol/L to 11.1 mmol/L). The study results were published online Sept. 8 by the Journal of the American Medical Association.

When the HbA1c, FPG, or 2-hour plasma glucose definition was used, the unadjusted prevalence was 14.3% for total diabetes, 9.1% for diagnosed diabetes, 5.2% for undiagnosed diabetes, and 38.0% for prediabetes in the overall population in 2011-2012, and 36.4% of patients who had diabetes were considered to have undiagnosed disease. Patients 65 years of age and older had a higher unadjusted prevalence (33%) than those 45 to 64 years of age (17.5%) and those 45 years of age or younger (5.0%). When the HbA1c or FPG definition of diabetes was used, the unadjusted prevalence of total diabetes was 12.3% and 25.2% of those with diabetes were considered to have undiagnosed disease.

Age-standardized prevalence of total diabetes using the HbA1c, FPG, or 2-hour plasma glucose definition was higher in non-Hispanic black patients, non-Hispanic Asian patients, and Hispanic patients than among non-Hispanic white patients (21.8%, 20.6%, 22.6%, and 11.3%, respectively; P<0.001 for all comparisons). Non-Hispanic Asian patients and Hispanic patients were more likely than other racial and ethnic groups to have undiagnosed diabetes. Between 1998-1994 and 2011-2012, the age-standardized prevalence of total diabetes using the HbA1c or FPG definition increased from 9.8% to 12.4%, with significant increases noted in all subgroups. Repeat measurements of HbA1c, FPG, and 2-hour plasma glucose as recommended by the American Diabetes Association could not be done because most patients had only 1 NHANES visit, and previous diabetes diagnoses were self-reported, the authors noted.

Although diabetes rates continue to increase, the authors of an accompanying editorial said that the study offers “a glimmer of hope” and noted that efforts to address environmental contributors to obesity and improve incentives for behavioral change in individual patients have increased, as have diabetes screening and prevention programs.

“Together, these multifaceted approaches addressing both environmental factors and individual behaviors appear to be slowing the increase in obesity and diabetes, and facilitating the diagnosis and management of diabetes,” they wrote. “Progress has been made, but expanded and sustained efforts will be required.”