Higher circulating orosomucoid and lower early-phase insulin secretion in midlife Japanese with slower glucose disposal during oral glucose tolerance tests

Objective We examined whether serum orosomucoid, an acute phase protein as with C-reactive protein, in addition to insulin resistance and beta-cell dysfunction, was involved in glucose disposal during oral glucose tolerance tests. Research design and methods 124 midlife Japanese (65 women, 66% with normal glucose tolerance) received dual-energy X-ray absorptiometry and 75 g oral glucose tolerance tests with multiple postload glucose and insulin measurements. Subjects were divided based on the relationship between postload and fasting glucose. Obesity measures, insulin resistance, insulin secretion, serum orosomucoid and adiponectin were cross-sectionally analyzed by analysis of variance and then Bonferroni’s multiple comparison procedure. Results In 10 subjects (group A) and 19 subjects (group B), postload glucose fell below fasting glucose at 1 h and 2 h, respectively. In the remaining 95 subjects (group C), postload glucose never fell below fasting glucose. The insulinogenic index was lower and area under the glucose curve was higher in groups B and C as compared to group A (both p