Relationships between changes in abdominal fat distribution and insulin sensitivity during a very low calorie diet in abdominally obese men and women

Abstract

Little is known about the association between abdominal obesity and insulin sensitivity during rapid weight loss. We assessed the role of visceral and subcutaneous fat as determinants of insulin sensitivity during rapid weight loss in obese persons with the metabolic syndrome. Twenty abdominally obese individuals [11 women and 9 men, body mass index (BMI) 35.8+/-3.5 kg/m2] with the metabolic syndrome underwent a very-low-calorie diet (VLCD) for nine weeks. At baseline, the computed tomography (CT) measured area of total (r=-0.50, p=0.033) and visceral fat tissue (r=-0.48, p=0.043), but not that of subcutaneous fat tissue (r=-0.34, p=0.17), correlated with insulin sensitivity as assessed by the quantitative insulin sensitivity check index after adjusting for sex and age. The 18 subjects who completed the study lost 14.8 kg during the VLCD. Total, visceral and subcutaneous abdominal fat tissue decreased by 22%, 29% and 17%, respectively. The decrease in total (r=-0.51, p=0.035) and subcutaneous abdominal fat (r=-0.57, p=0.017), but not visceral fat (r=0.11, p=0.68), correlated with the increase in insulin sensitivity. Waist circumference did not offer any additional information concerning abdominal fat distribution or insulin sensitivity compared with that provided by BMI at baseline or after weight loss. The waist/hip ratio was not associated with the CT measures of abdominal fat distribution or insulin sensitivity. Total abdominal fat may be more important than its compartmentalisation in abdominally obese individuals with the metabolic syndrome. In this subgroup of individuals with obesity, the measurement of waist circumference and the waist/hip ratio offered little additional information over that provided by BMI at baseline or after weight loss.