The quantitative insulin sensitivity check index QUICKI predicts the onset of type 2 diabetes better than fasting plasma insulin in obese subjects: a 5-year follow-up study.

The aim of the present study was to evaluate the predictive value of QUICKI and fasting plasma insulin (FPI0 as predictors of the onset of type 2 diabetes mellitus. We performed a five-year follow-up study in a sample of middle-aged subjects with at least one of the following risk factors; hypertension defined as systolic blood pressure >or=160 mmHg and/or diastolic blood pressure >or=90 mmHg or medication for hypertensin, obesity defined as a body mass index >or=30 kg/m(2) and/or a waist-to-hip ratio >or=1.00 in men and >or=0.88 in women, or a family history of type 2 DM. When the QUICKI index was used to compare the tertile with the lowest risk to the tertile of the highest risk of obese subjects. Odd's Ratio (OR) for type 2 diabetes was 7.77 (95% CI 1.39-202.24). For FPI, the respective OR's were 2.84 (95% CI 0.82-9.82) and 3.96 (95% CI 1.02-15.48). QUICKI and fasting insulin did not have a statistically significant predictive value among non-obese subjects. Concerning QUICKI, the subjects in the tertiles at the medium and highest risk had a higher risk for type 2 DM than the corresponding tertiles of FPI among obese subjects.