(OGTT = oral glucose tolerance test
; 12-m = 12-month; 2-to-4-y = 2-to-4-year.) Factors that raise risk of prediabetes or diabetes Older age 1.06 Higher initial fasting glucose 2.67 Higher initial OGTT 1.47 12-m belly fat 2.65 2-to-4-y belly fat gain 3.16 Note: Table made from bar graph.
Possibility of evaluating islet [sz]-cell function by oral glucose tolerance test
in epidemiological study on diabetes mellitus – Analysis of euglycemic clamp study in 468 non-diabetic pima indians (in Chinese).
De Vries et al., "Intraindividual variation of glucose, specific insulin and proinsulin concentrations measured by two oral glucose tolerance tests
in a general Caucasian population: the Hoorn Study," Diabetologia, vol.
Sensitivity specificity predictive values were calculated of GCT by comparing with oral glucose tolerance test
(GTT) as gold standard.
All patients without a prior diagnosis of diabetes underwent assessment with an oral glucose tolerance test
, following the 2007 recommendation.
"For example, an oral glucose tolerance test
with symptoms might be followed up with a fasting plasma glucose," she says.
* Pre-diabetes can be diagnosed if the fasting plasma glucose is 6.1 - 6.9 mmol/l (impaired fasting glucose) or the 2-hour plasma glucose value following a 75 g oral glucose tolerance test
is 7.8 - 11.0 mmol/l (impaired glucose tolerance).
The A1C would join two previous diagnostic tests for diabetes, FPG (fasting plasma glucose) and the OGTT (oral glucose tolerance test
), both of which require overnight fasting.
In the United States, nearly 13 percent of adults age 20 and older have diabetes, but 40 percent of them have not been diagnosed, according to epidemiologists from the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC), whose study includes newly available data from an Oral Glucose Tolerance Test
adults are known to have prediabetes, a condition defined as having impaired fasting glucose (plasma glucose level of 100 to <126 mg/dL after an overnight fast), impaired glucose tolerance (plasma glucose level of 140 to <200 mg/dL after a 2-hour oral glucose tolerance test
), or both (1-3).
Outcome Measures: Outcome measures included the primary endpoint [HB[A.sub.1c], as well as fasting and 75-g oral glucose tolerance test
, plasma glucose, plasma insulin and insulin-sensitivity indices.