Metabolic Characteristics in Individuals

OBJECTIVEdIndividuals with impaired glucose tolerance (IGT) are at high risk for devel-oping type 2 diabetes mellitus (T2DM). We examined which characteristics at baseline predicted the development of T2DM versus maintenance of IGT or conversion to normal glucose tolerance. RESEARCHDESIGNANDMETHODSdWe studied 228 subjects at high risk with IGT who received treatment with placebo in ACTNOWandwho underwent baseline anthropometric measures and oral glucose tolerance test (OGTT) at baseline and after a mean follow-up of 2.4 years. RESULTSdIn a univariate analysis, 45 of 228 (19.7%) IGT individuals developed diabetes. After adjusting for age, sex, and center, increased fasting plasma glucose, 2-h plasma glucose, ΔG0–120 during OGTT, HbA1c, adipocyte insulin resistance index, ln fasting plasma insulin, and ln ΔI0–120, as well as family history of diabetes and presence of metabolic syndrome, were associated with increased risk of diabetes. At baseline, higher insulin secretion (ln [ΔI0–120/ ΔG0–120]) during the OGTT was associated with decreased risk of diabetes. Higher b-cell func-tion (insulin secretion/insulin resistance or disposition index; ln [ΔI0–120/ΔG0–120 3 Matsuda index of insulin sensitivity]; odds ratio 0.11; P, 0.0001) was the variablemost closely associate