Relation of regional fat distribution to insulin sensitivity in postmenopausal women

Objective: To examine the relation between insulin sensitivity and total and regional body fat in nonobese postmenopausal women. Design: Cross-sectional study. Setting: A clinical research center. Patient(s): Twenty-seven women in the early postmenopausal period, with a mean (+/-SD) age of 50.8 +/- 4.1 years, who had had their last menstrual period 6 months to 3 years before the study. None were taking hormone replacement therapy, and all had an FSH level of >35 mIU/mL, a body mass index of <30 kg/m(2), and a waist circumference of <94 cm. Intervention(s): Computed tomography scans at the L4-5 vertebral disk space, dual-photon x-ray absorptiometry scans, and euglycemic hyperinsulinemic clamps were performed. Main Outcome Measure(s): Intraabdominal fat, subcutaneous abdominal fat, sagittal diameter, total body fat, percent body fat, and insulin sensitivity. Result(s): The natural log of insulin sensitivity correlated significantly with intraabdominal fat (r = -.39), subcutaneous fat (r = -.43), and sagittal diameter (r = -.48). After adjusting for total fat, sagittal diameter remained significantly related to insulin sensitivity. Conclusion(s): Central abdominal fat is inversely and independently related to insulin sensitivity after adjusting for total fat in women in the early postmenopausal period. Efforts to reduce either subcutaneous abdominal fat or intraabdominal fat should be helpful in reducing the risk of noninsulin-dependent diabetes mellitus in postmenopausal women. (Fertil Steril(R) 2000;73:61-5. (C) 1999 by American Society for Reproductive Medicine.)