Upper limit of fasting plasma glucose level defined by oral glucose tolerance test in Japanese subjects

摘要

Aims: There are conflicting interpretations regarding the normal fasting plasma glucose level in Japanese subjects. We therefore aimed to define the upper limit of fasting plasma glucose level. Methods: A total of 962 subjects who had a 75-g oral glucose tolerance test were examined. Subjects were divided into two groups - post-load normal glycemic group (2-h plasma glucose <140. mg/dL) and post-load hyperglycemic group (2-h plasma glucose ≥ 140. mg/dL). Results: There were 434 subjects with post-load normal glycemia and 528 subjects with post-load hyperglycemia. Receiver operating characteristic curve (ROC) demonstrated that the optimal cut-off value for predicting post-load hyperglycemia was a fasting plasma glucose of 99. mg/dL (area under ROC curve = 0.81), which had a sensitivity, specificity, and overall diagnostic accuracy of 68%, 81%, 74%, respectively. Conclusions: These data suggest that for predicting post-load hyperglycemia, the optimal cut-off value of fasting plasma glucose was 99. mg/dL in Japanese subjects. Thus, the current cut-off value of fasting plasma glucose of 110. mg/dL in Japan might be lowered.