Laboratory assessments
hypoglycemic
Venous blood samples were drawn in the morning after an overnight fast. Fasting plasma glucose (FPG), HbA1c, hemoglobin, serum creatinine, albumin, alanine transaminase, aspartate transaminase, total cholesterol, and triglycerides were measured in local laboratories. Patients had breakfast and take their daily hypoglycemic agents. The blood sample was collected 2 hours later to measure 2-hour postprandial plasma glucose (2-h PPG). Glycated hemoglobin HbA1c was tested using ion-exchange high-performance liquid chromatography, capillary electrophoresis, immunoassay, enzymatic assay or boronate affinity chromatography in local laboratories. Local laboratories were required to perform 10 samples comparison quarterly with the Department of Laboratory Medicine, Zhongshan Hospital, Fudan University, which is an HbA1c Secondary Referral Laboratory certificated by the National Glycohemoglobin Standardization Program (NGSP) (