USE OF THE 1997 AMERICAN-DIABETES-ASSOCIATION DIAGNOSTIC-CRITERIA FORDIABETES IN A HONG-KONG CHINESE POPULATION

OBJECTIVE - Recently, the American Diabetes Association (ADA) has prop osed revised diagnostic criteria for diabetes. lowering of the fasting plasma glucose (FPG) cutoff value is intended to reduce the discrepan cy with the 2-h plasma glucose (PG) cutoff value and to encourage the use of FPG. We have applied these new criteria to data collected from a population-based prevalence survey in Hong Kong Chinese subjects of working age. RESEARCH DESIGN AND METHODS - The results of 1,513 oral g lucose tolerance tests (OGTTs) from a previously published prevalence survey of glucose intolerance and cardiovascular risk factors in a Hon g Kong Chinese working population were reexamined using the new criter ia. Of the 1,513 subjects, 27 had a known history of diabetes. Of the remaining 1,486 subjects, 228 were also selected randomly for a second OGTT without prior knowledge of the result of the first test. RESULTS - After exclusion of the 27 subjects with a known history of diabetes , the crude prevalence of diabetes was 2.83% (n = 42) when the World H ealth Organization's (WHO) criteria were applied. When the criterion o f FPG greater than or equal to 7.0 mmol/l was used, as recommended by the ADA, the prevalence of diabetes was 1.41% (n = 21). Twenty-nine su bjects (1.95%) with FPG <7.0 mmol/l had a 2-h PG greater than or equal to 11.1 mmol/l. Eight subjects (0.53%), previously without a diagnosi s of diabetes according to the WHO criteria (FPG <7.8 mmol/l and 2-h P G <11.1 mmol/l), had FPG between 7.0 and 7.8 mmol/l and were classifie d as having diabetes by the ADA criteria. This classification gave a n et change of -1.42% in the prevalence of diabetes between the use of F PG greater than or equal to 7.0 mmol/l alone and the use of WHO criter ia. Among the 1,486 subjects with no known history of diabetes, those classified as having diabetes according to the ADA FPG criterion alone had higher HbA(1c) and fructosamine levels than diabetic subjects def ined by the WHO criteria. Of the 228 subjects for whom two FPG measure ments were available, those who had consistent definitions (diabetes, impaired fasting glucose, normal fasting glucose) on both occasions we re considered to have reproducible tests, giving an overall reproducib ility of 90.8% (207 of 228). CONCLUSIONS - Compared with the WHO crite ria, the use of FPG to diagnose diabetes, as recommended by the ADA, w as a more reproducible test and identified those subjects who had a gr eater degree of hyperglycemia. Although lowering of the cutoff value f rom 7.8 to 7.0 mmol/l increased the number of diagnoses among subjects with low FPG, the omission of the 2-h PG would lead to fewer subjects having their diabetes diagnosed.