Correction to the 2010 Report on the Diagnosis and Classification of Diabetes

Having been a member of the 1997 Expert Committee on the Diagnosis and Classification of Diabetes Mellitus (1), I wish to correct an error in the 2010 report on the diagnosis and classification of diabetes mellitus (2), published in the January 2010 supplement to Diabetes Care. The report states (page S67, first column, third paragraph) that the 1997 Expert Committee lowered the fasting plasma glucose (FPG) concentration diagnostic criterion for diabetes from ≥140 mg/dl to ≥126 mg/dl “using the observed association between FPG levels and presence of retinopathy as the key factor with which to identify threshold glucose level.” In actuality, the FPG was lowered to establish “equivalence” between the FPG and the 2-h oral glucose tolerance test (OGTT) value for the diagnosis of diabetes. As stated in the 1997 Expert Committee report (1) (page 1190, second column), “Almost all individuals with FPG ≥140 mg/dl have 2hPG ≥200 mg/dl if given an OGTT, whereas only about one-fourth of those with 2hPG ≥200 mg/dl and without previously known diabetes have FPG ≥140 mg/dl…. Thus, the cutpoint of FPG ≥140 mg/dl defined a greater degree of hyperglycemia than did the cutpoint of 2hPG ≥200 mg/dl. It is the consensus of the Expert Committee that this discrepancy is unwarranted and that the cutpoint values for both tests should reflect a similar degree of hyperglycemia and risk of adverse outcomes.” Table 5 of the 1997 report identified three studies that showed the FPG level that, if used alone, yielded the same prevalence of diabetes as did a 2-h value on the OGTT and was the basis of the FPG ≥126 mg/dl diagnostic criterion for diabetes. The 1997 Expert Committee was furnished the data on the three studies concerning retinopathy mentioned in the 2010 report (2), but these were sent to the committee members following the meeting at which the decision was agreed upon. Furthermore, these data were for information only as no comments from the committee were solicited. To confirm this point, the 2003 Expert Committee report (3) stated (page 3161, first column, third paragraph), “The 2-h criterion of 200 mg/dl identifies a larger fraction of the population as having diabetes than the previous fasting criterion of 140 mg/dl. To eliminate, or at least reduce this discrepancy, the Expert Committee in 1997 recommended lowering the fasting criterion to 126 mg/dl.”

I would hope that the 2011 report on the diagnosis and classification of diabetes mellitus will correct the misinformation in the 2010 report.