Diabetes based on 2-h plasma glucose among those classified as having prediabetes based on fasting plasma glucose or A1c.

Objective: Determine the prevalence of diabetes using 2-h plasma glucose among people who otherwise would be categorized as having prediabetes based on A1c and fasting glucose, and to determine whether those people were more likely to have cardiometabolic risk factors.

Methods: Among 3644 adults with prediabetes based on A1c and fasting glucose in the 2005-2014 National Health and Nutrition Examination Survey, a cross-sectional survey of the US general population, we estimated the percentage who would be categorized as having diabetes based on having a 2-h plasma glucose ⩾200 mg/dL. We calculated odds ratios of cardiometabolic risk factors associated with having 2-h plasma glucose ⩾200 mg/dL.

Results: A total of 6.9% would be categorized as having diabetes based on 2-h plasma glucose. The adjusted odds ratios (95% confidence interval) associated with having 2-h plasma glucose ⩾200 mg/dL were significant for total hypertension (2.06, 1.35-3.14), high triglycerides (1.64, 1.10-2.44), low high-density lipoprotein cholesterol (1.55, 1.01-2.39), albuminuria (2.05, 1.33-3.14) and elevated alanine aminotransferase (1.78, 1.09-2.91), but not for other cardiometabolic risk factors.

Conclusion: A total of 6.9% of people categorized as having prediabetes based on A1c and fasting glucose would be categorized as having diabetes based on 2-h plasma glucose. They were more likely to have hypertension, high triglycerides, low high-density lipoprotein cholesterol, albuminuria and elevated alanine aminotransferase.