Purpose: We evaluated the potential application of sonography to monitor alterations in abdominal fat thickness in obese women before and after dieting.
Methods: This study included 40 obese women (mean age, 42.2 +/- 9.4 years; mean body mass index [BMI], 36.0 +/- 5.9 kg/m2) who underwent a 3-month low-calorie diet. Height, weight, waist circumference (WC), and hip circumference (HC) were measured. BMI and waist-to-hip ratio (WHR) were calculated. Abdominal subcutaneous (S) and intra-abdominal preperitoneal (P) fat were measured at their maximum (max) and minimum (min) thickness sites using a 7.5-MHz linear-array probe. Intra-abdominal visceral (V) fat was measured using a 3.5-MHz convex-array probe. Measurements were taken before and after caloric restriction.
Results: The mean weight was reduced from 88.6 +/- 17.1 kg to 83.0 +/- 15.9 kg (p < 0.0001). The mean changes in S(min) (r = 0.376, p = 0.017), S(max) (r = 0.508, (p = 0.001), P(min) (r = 0.439, p = 0.005), and V (r = 0.365, p = 0.022) fat thicknesses were positively correlated with change in weight; the change in P(max) fat thickness showed the best and most significant correlation (r = 0.591, p < 0.0001). BMI (r = 0.969, p < 0.0001), WC (r = 0.510, p = 0.001), and HC (r = 0.422, p = 0.007) changes were also positively correlated with weight change, but the WHR change (r = 0.019, p > 0.05) was not.
Conclusions: All the abdominal fat layers, particularly the intra-abdominal P fat, will decrease in response to loss of body fat by dieting. Sonography seems to be useful in monitoring small variations in the thicknesses of abdominal S and intra-abdominal P and V fat.
Copyright 2002 Wiley Periodicals, Inc.