Abstract

Objective We examine the prevalences of diagnosed diabetes, and undiagnosed diabetes and prediabetes using fasting and 2-hour OGTT glucoses, in the U.S. during 2005–2006. We compare prevalences to those in 1988–1994.

Research Design and Methods In 2005–2006, the National Health and Nutrition Examination Survey included a probability sample of 7267 persons age ≥12 years. Participants were classified on glycemic status by interview for diagnosed diabetes, and fasting and 2-hour glucoses measured in subsamples.

Results In 2005–2006, the crude prevalence of total diabetes in persons age ≥20 years was 12.9%, of which approximately 40% was undiagnosed. In persons age ≥20 years, the crude prevalence of IFG was 25.7% and of IGT was 13.8%, with almost 30% having either. Over 40% of individuals had diabetes or prediabetes. Almost one-third of the elderly had diabetes and three-quarters had diabetes or prediabetes. Compared to non-Hispanic whites, age/sex standardized prevalence of diagnosed diabetes was about twice as high in non-Hispanic blacks (p<0.0001) and Mexican Americans (p=0.0001), while undiagnosed diabetes was not higher. Crude prevalence of diagnosed diabetes in persons age ≥20 years rose from 5.1% in 1988-1994 to 7.7% in 2005-2006 (p=0.0001); this was significant after accounting for age/sex, particularly in non-Hispanic blacks. Prevalences of undiagnosed diabetes and prediabetes were generally stable, although the proportion of total diabetes that was undiagnosed decreased in Mexican Americans.

Conclusions Over 40% of persons age ≥20 years have hyperglycemic conditions. Prevalence is higher in minorities. Diagnosed diabetes has increased over time, but other conditions have been relatively stable.