Performance Characteristics of the New Definition of Diabetes - The Insulin Resistance Atherosclerosis Study

OBJECTIVE- A1C >= 6.5% has been recently proposed as the defining criterion for diabetes. However, performance characteristics of this definition have not been described. RESEARCH DESIGN AND METHODS - in the Insulin Resistance Atherosclerosis Study, we compared new to previous definitions of diabetes: 1999 World Health Organization (DM1999WHO) and 2003 American Diabetes Association based on fasting glucose alone (DMFPG126). RESULTS - Participants with A1C >=-6.5%, DM1999WHO and DMFPG126 were 44 (5.2%),1.32 (15.4%), and 61 (7.1%), respectively. In individuals With DM1999WHO, mean, median, and interquartile range of A1C were 6.3, 5.9, and 5.5-6.6%, respectively; in individuals with DMFPG126, mean, median, and iraerquartile range of A1C were 7.0, 6.6, and 6.0-7.1%. CONCLUSIONS- A1C >= 6.5% identifies fewer individuals than DM1999WHO or DMFPG126 Studies are needed to determine that A1C >= 6.5% compromises neither blood pressure and lipid management in early diabetes nor the implementation of lifestyle interventions for diabetes prevention.