Obstructive sleep apnoea, glucose tolerance and liver steatosis in obese women

In this study of obstructive sleep apnoea (OSA), glucose tolerance and liver steatosis in females from an obesity unit, 45 patients (mean age 46.8 years, mean body mass index 39.4 kg/m(2), all non-diabetic and alcohol abstainers) underwent nocturnal polysomnography, a 2 h oral glucose tolerance test and abdominal ultrasonography. OSA, defined as an apnoea-hypopnoea index (AHI) of > or = 10 events/h, was present in 20 patients (44%). Impaired glucose tolerance (IGT) was found in eight patients (40%) with OSA and three patients (12%) without OSA; there was a positive linear relationship between AHI and post-load glucose levels. On multivariate logistic regression analysis, IGT was predicted by OSA independently of age, waist circumference, systolic blood pressure and current smoking. Liver steatosis was present in 37 women (82.2%), of whom six had grade III steatosis. Of the variables tested, IGT was the only predictor of grade III steatosis. In conclusion, OSA is an independent predictor of IGT which, in turn, is associated with severe liver steatosis in an obesity unit-based sample of women.