OBJECTIVE: One-hour plasma glucose (1-h PG) during the oral glucose tolerance test (OGTT) is an accurate predictor of type 2 diabetes. We performed a meta-analysis to determine the optimum cutoff of 1-h PG for detection of type 2 diabetes using 2-h PG as the gold standard. RESEARCH DESIGN AND METHODS: We included 15 studies with 35,551 participants from multiple ethnic groups (53.8% Caucasian) and 2,705 newly detected cases of diabetes based on 2-h PG during OGTT. We excluded cases identified only by elevated fasting plasma glucose and/or HbA1c. We determined the optimal 1-h PG threshold and its accuracy at this cutoff for detection of diabetes (2-h PG ≥11.1 mmol/L) using a mixed linear effects regression model with different weights to sensitivity/specificity (2/3, 1/2, and 1/3). RESULTS: Three cutoffs of 1-h PG, at 10.6 mmol/L, 11.6 mmol/L, and 12.5 mmol/L, had sensitivities of 0.95, 0.92, and 0.87 and specificities of 0.86, 0.91, and 0.94 at weights 2/3, 1/2, and 1/3, respectively. The cutoff of 11.6 mmol/L (95% CI 10.6, 12.6) had a sensitivity of 0.92 (0.87, 0.95), specificity of 0.91 (0.88, 0.93), area under the curve 0.939 (95% confidence region for sensitivity at a given specificity: 0.904, 0.946), and a positive predictive value of 45%. CONCLUSIONS: The 1-h PG of ≥11.6 mmol/L during OGTT has a good sensitivity and specificity for detecting type 2 diabetes. Prescreening with a diabetes-specific risk calculator to identify high-risk individuals is suggested to decrease the proportion of false-positive cases. Studies including other ethnic groups and assessing complication risk are warranted.
Institute(s)Institute for Pancreatic Beta Cell Research (IPI)
GrantsFinnish Diabetes Research Foundation Foundation for Life and Health in Finland Signe and Ane Gyllenberg Foundation Finnish Medical Society Paavo Nurmi Foundation State Research Funding via the Helsinki University Hospital Perklen Foundation Narpes Health Care Foundation Ahokas Foundation Swedish Cultural Foundation in Finland Ollqvist Foundation Academy of Finland Folkhalsan Research Foundation Sigrid Juselius Foundation University of Helsinki Nordic Center of Excellence in Disease Genetics European Union (EXGENESIS project) European Union (MOSAIC project) Ministry of Education in Finland Municipal Health Care Center and Hospital in Jakobstad Health Care Center in Vasa Finnish Cultural Foundation Central Fund Division of Intramural Research of National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health Japan Health Promotion Foundation Toyama Medical Association Mitsubishi Roche Diagnostics Bayer Pharma Boehringer Ingelheim Merck DCURE Foundation Eli Lilly, Italy Health Care Center in Narpes Health Care Center in Korsholm Pfizer Inc. Regeneron Pharmaceuticals European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant European Foundation for the Study of Diabetes Fondazione Romeo ad Enrica Invernizzi-Milano, an EFSD/Sanofi program Italian Ministry of Health-Ricerca Corrente FoRiSID, Rome, Italy Sanofi