Diabetes mellitus: test strategies for diagnosis and management

Fasting plasma glucose determination is the test of choice for diagnosis of diabetes. Glucose tolerance testing should be reserved for patients with borderline fasting values or possible diabetic complications and those suspected of having gestational diabetes. Strict attention to patient variables is essential if glucose tolerance testing is to be of value. The diagnosis of diabetes should be reserved for those patients with symptoms and unequivocal hyperglycemia, those with fasting plasma glucose values of 140 mg/dl or more repeatedly, and those with glucose tolerance test values of 200 mg/dl or more at two hours and at least one other time.