The Effect of Body Fat Disribution on Glucose, Lipid Metabolism and Grewth Hormone Secretion in Obesity / 대한내분비학회지

ABSTRACT

BACKGROUND: Body fat distribution, rather than the level of obesity per se, appears to be a strong predictor of abnormalities in metabolic complication. Visceral fat accumulation is significantly correlated with glucose intolerance and constitutes as an independent risk factor for the diabetes mellitus. METHODS: We investigated the impact of body fat distribution on the glucose, lipid metabolism and growth hormone secretion in obese subjects with varying glucose tolerance and lean controls matched with sex and age. 69 obese Koreans (34 men, 35 women; 43.8 yrs) and 21 lean Koreans (10 men, 11 women; 40.8 yrs) were recruited. Anthropometric measurement and impedence for measurement of total body fat, and computed tomography for visceral and subcutaneous fat area at umbilicus level were performed. All subjects underwent a standard oral glucose tolerance test and GH stimulation test by L-dopa. RESULTS: The results are summarized as follows. 1. Obese patients had greater ideal body weight (%, IBW) and lean body mass (LBM) than lean controls. But no significant differences were found in IBW and LBM between 3 obese groups. 2. The 25 obese NIDDM had the highest FFA-AUC during OGTI and the lowest GH-AUC to L-Dopa stimulation test. The insulin-AUC during OGTT was the highest in 24 obese subjects with normal glucose tolerance. 3. All male groups have VSR of more than 0.4, which has been designated visceral fat obesity. In contrast all female groups have VSR of lesser than 0.4 but obese DM subjects have the highest VSR. Visceral fat area per body weight ratio(VWR) showed increasing tendency in obese, IGT, and DM group. 4. Waist circumference and VWR showed strong correlation with metabolic parameters among anthropometric parameters. They were positively correlated with FFA-AUC during OGTT and negatively correlated with GH-AUC to L-dopa stimulation. CONCLUSION: Visceral fat accumulation are associated with insulin resistance, dyslipidemia and impairment of growth hormone secretion via increase of free fatty acid. The simple waist circumference may provide a more practical indicator that correlated with aMominal fat distribution and metabolic complications associated with obesity.