Recommendations for Revision of Chinese Diagnostic Criteria for Metabolic Syndrome: A Nationwide Study

Background: Diagnostic criteria for metabolic syndrome (MS) proposed by the Chinese Diabetes Society (CDS) may have limitations because an additional 2-h postprandial plasma glucose (2-h PPG) test is required to diagnose hyperglycemia. The aim of this study was to revise the CDS-MS criteria by removing the 2-h PPG test and determining the optimal fasting plasma glucose (FPG) cut-off for a diagnosis of hyperglycemia in the Chinese population.

Methods: The study population was from the 2007-08 China Diabetes and Metabolic Disorders Study. The optimal FPG diagnostic cut-off value was determined using receiver operating characteristic curves. Hyperglycemia defined using CDS-MS criteria was the end-point. Agreement between different diagnostic methods was assessed using κ values.

Results: The study enrolled 46 239 participants (mean age 44.95 years). The optimal diagnostic cut-off for FPG was found to be 5.62 mmol/L, which showed a sensitivity of 66.92%, a specificity of 89.09%, and an area under the curve of 0.848. Using this diagnostic criterion, the standardized prevalence of MS was similar to that using the CDS-MS criteria (18.26% vs 17.89%, respectively), with both values being lower than those obtained using conventional international criteria (20.64-26.67%). Compared with the CDS-MS criteria, the recommended FPG cut-off showed better agreement (κ) with international criteria: 0.695, 0.774, and 0.730 with the International Diabetes Federation (IDF), revised Adult Treatment Panel III, and Joint Interim Statement of the IDF criteria, respectively.

Conclusions: We recommend eliminating the 2-h PPG blood test and lowering the FPG diagnostic cut-off value to 5.6 mmol/L in the CDS-MS diagnostic criteria.