<b>Objective </b>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 cut-off of
1-h PG to detect type 2 diabetes using 2-h PG as the gold standard.
<p><b>Research
Design and Methods </b>We included 15 studies with 35,551 participants
from multiple ethnic groups (53.8% Caucasian) and 2705 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 cut-off to
detect 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). </p>
<p><b>Results</b> Three cut-offs 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 cut-off of 11.6 mmol/L
(95% CI 10.6, 12.6) had a sensitivity 0.92 (0.87, 0.95), specificity of 0.91
(0.88, 0.93), AUC 0.939 (95% confidence region for sensitivity at a given specificity:
0.904, 0.946), and a positive predictive value of 45%.</p>
<p><b>Conclusions</b> The 1-h PG of ≥ 11.6 mmol/L during OGTT <a>has a </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.</p>