The prevalence of diabetes, association with cardiovascular risk factors and implications of diagnostic criteria (ADA 1997 and WHO 1998) in a 1996 community-based population study in Hong Kong Chinese

Aims While the American Diabetes Association (ADA) 1997 diagnostic criteria advocate the use of fasting plasma glucose only, the World Health Organiza tion (WHO) criteria retain the use of the standard oral glucose tolerance t est (OGTT). The present study evaluated the relative merit of the respectiv e diagnostic criteria in Chinese. Methods Data collected for the Hong Kong Cardiovascular Risk Factor Prevale nce Study was analysed. This was a representative population-based study, c onducted from 1995 to 1996 among 2900 Chinese subjects aged 25-74 years usi ng a 75-g OGTT. Results The prevalence of diabetes (known plus unknown) was 6.2% (95% confi dence interval 5.3-7.1%), 9.2% (8.1-10.3%), and 9.8% (8.7-10.9%) based on A DA 1997, WHO 1985 and WHO 1998 criteria, respectively, with a very high pre valence in older subjects. The 2451 subjects classified as normal under ADA 1997 criteria were heterogenous: 15.3% had impaired glucose tolerance; 2.1 % had diabetes under WHO 1998 criteria. These latter two smaller groups had cardiovascular risk profiles comparable to that found among the impaired f asting glucose subjects (under ADA), but worse than that among the concorda nt normal glucose tolerance subjects. Conclusions The ADA criteria underestimate both diabetes prevalence and car diovascular risk in this population. Hence fasting glucose alone is an inad equate approach and OGTT should be retained to identify at-risk individuals in both clinical diagnosis and epidemiological studies.