Context: Menopause is associated with an increased incidence of insulin resistance and diabetes.

Objective: The aim of this study was to explore the lipid deposition in liver and skeletal muscle and investigate the association with insulin sensitivity in post- and premenopausal women.

Design, setting, participants and measurements: Single-centre cross-sectional study of 55 healthy women between 45- and 60 years of age. We measured lipid deposition in the liver with MR spectroscopy, intramuscular- and intraabdominal lipid deposition with MRI, body composition with a DEXA-scan and insulin sensitivity with the composite Matsuda Index.

Outcomes: We studied the association between fat distribution, ectopic lipid deposition and insulin sensitivity in pre- and postmenopausal women.

Results: Postmenopausal women had an increased lipid deposition in the liver (0.68% (0.44-0.99) vs. 0.49% (0.38-0.64), p=0.01) and skeletal muscle (3% (2-4) vs. 2% (1-3), p=0.001) and had a 28% lower Matsuda insulin sensitivity index during an OGTT (6.31±3.48 vs. 8.78±4.67, p=0.05) compared to premenopausal women. Total fat mass and leg fat mass were stronger predictors of ectopic lipid deposition and visceral fat mass was a stronger predictor of both ectopic lipid deposition and insulin resistance in postmenopausal women compared to premenopausal women.

Conclusions: For a given sub cutaneous- and visceral fat depot size, postmenopausal women show increased ectopic lipid deposition and -insulin resistance compared to premenopausal women. It is suggested that lipid deposition in liver and skeletal muscle may represent important mechanistic links between the changes in fat depots and the increased incidence of insulin resistance seen after menopause.