LACK OF AGREEMENT BETWEEN THE WORLD-HEALTH-ORGANIZATION CATEGORY OF IMPAIRED GLUCOSE-TOLERANCE AND THE AMERICAN-DIABETES-ASSOCIATION CATEGORY OF IMPAIRED FASTING GLUCOSE

OBJECTIVE - To study the concordance between the 1997 American Diabete s Association (ADA) impaired fasting glucose (IFG) category with the W orld Health Organization (WHO) impaired glucose tolerance (IGT) status in a population with a high prevalence of diabetes. RESEARCH DESIGN A ND METHODS - We analyzed the oral glucose tolerance tests (OGTTs) carr ied out at the Institute Nacional de la Nutricion Salvador Zubiran (IN NSZ) central laboratory from June to December 1997. We included patien ts with fasting plasma glucose (FPG) between 60 and 160 mg/dl. The res ults from the glucose tolerance test were selected as the gold standar d. RESULTS - Among the 1,802 glucose tolerance test results available for analysis, 1,706 fulfilled the requirements to be included. Diabete s and IGT were remarkably more frequently diagnosed when the WHO crite ria were applied. The new ADA criteria failed to diagnose 69% of WHO d iabetic patients and the vast majority of WHO glucose-intolerant subje cts. Using the new criteria, 82% were considered normal. Of the IFG su bjects, 39% were classified as diabetic and 23% were normal according to the 2-h postchallenge glucose values. Only 37% of the IFG patients were, in fact, glucose intolerant according to the WHO criteria. CONCL USIONS - Our results clearly show that the 1997 ADA criteria are less sensitive for diagnosing diabetes than OGTT-based WHO criteria. Even m ore important, there is poor agreement between the WHO category of IGT and the ADA category of IFG.