A single blood sample can be used to test for both fasting glucose and hemoglobin A1c (HbA1c) levels in order to identify undiagnosed diabetes in the population, according to a study published in the Annals of Internal Medicine. This confirmatory definition, the authors say, has high positive predictive value for future risk for diagnosed diabetes and is associated with risk for major clinical outcomes. Current clinical definitions of diabetes often require repeated testing to confirm elevated levels of glucose or HbA1c in order to reduce the possibility of a false-positive diagnosis. “Using a repeated test on a new sample from a subsequent visit to confirm diabetes can be logistically cumbersome, inconvenient, and expensive and can delay patient care,” writes K.M. Venkat Narayan, MD, from Emory University in Atlanta in an editorial accompanying the study. “Whether two tests from the same blood sample can be used for both screening and confirmation is an intriguing question with practical relevance.” In the present study researchers analyzed 25-year data from 12,268 participants of the Atherosclerosis Risk in Communities) study without diagnosed diabetes at baseline. Confirmed, undiagnosed diabetes was defined as elevated levels of fasting glucose (≥7.0 mmol/L and HbA1c (≥6.5%) from a single blood […]