LAUSR

AIMS To describe the roles of intra-abdominal fat and its change in the remission of impaired glucose tolerance (IGT) to normal glucose tolerance (NGT). METHODS We followed 157 Japanese Americans with IGT at baseline for 10-11 years without external intervention. We measured intra-abdominal and abdominal subcutaneous fat area (IAFA and ASFA) by computed tomography at baseline and at 5-6 years of follow-up. Change in IAFA and ASFA (ΔIAFA and ΔASFA) were calculated by subtracting baseline fat area from 5-6 year follow-up fat area. Glucose and insulin at fasting and during a 75-g oral glucose tolerance test, insulinogenic index (IGI [Δinsulin/Δglucose (30-0 min)]) and homeostasis model assessment for insulin resistance (HOMA-IR) were measured at baseline. RESULTS Fourty-four subjects remitted to NGT. Among those with lower IAFA (≤median 91.31 cm2) and the lowest tertile of ΔIAFA, 45% remitted, while with higher IAFA (>91.31 cm2) and the highest tertile of ΔIAFA, only 12.5% remitted. ΔIAFA was significantly associated with remission to NGT (multiple-adjusted odd ratio [1-SD decrease] 1.93, 95% CI 1.10-3.36) independent of IAFA, ASFA, ΔASFA, IGI, HOMA-IR, age, sex, and family history of diabetes. CONCLUSIONS In the natural history of IGT, change in intra-abdominal fat was associated with remission to NGT.