Abstract
To evaluate insulin resistance clinically, we studied the reduction of senlm free fatty acids (%FFA 30') during the initial 30 minutes of oral glucose tolerance tests (OGTT) in 93 subjects-48 men and 45 women with a mean age was 47.1±13.2 years (mean±SD). We also conducted hyperinsulinemic euglycemic clampingin 18 obese subjects and calculated glucose infusion rates (GIRs). Blood glucose, insulin, fasting lipids, and %FFA 30'were measured during 75 g-OGTr. Multiple regression analysis was conducted using Akaike's infbrmation criterion. When primary correlations between %FFA 30'and other factors were evaluated, %FFA 30' was lower in subjects with glucose intolerance-a trend that increased with obesity. A significant correlation was seen between %FFA 30' and the results of homeostasis model assessment (r=-0.24, p=0.023). When GIR was calculated in obese subjects, %FFA 30' correlated significantly with 1/GIR (r=-0.51, p=0.031). The results of multiple regression analysis showed that a combination of 1/GIR, FFA 120', HbA1c, triglycerides, and body mass index was the most appropriate model to explain %FFA 30'. These findings suggest that the reduction of %FFA 30' during OGTT reflects the severity of insulin resistance.
