Impact of weight loss-associated changes in detailed body composition as assessed by whole-body MRI on plasma insulin levels and homeostatis model assessment index

• Published in: European journal of clinical nutrition 2017-02, Vol.71 (2), p.212-218
• Main Authors: Pourhassan, M, Glüer, C-C, Pick, P, Tigges, W, Müller, M J
• Format: Article
• Language: English
• Subjects: 59/57; 692/499; 692/699/1702; Adipose tissue; Adipose Tissue - diagnostic imaging; Adipose Tissue - physiopathology; Adiposity - physiology; Adult; Aged; Bariatric Surgery; Body composition; Body Composition - physiology; Body fat; Body mass index; Body size; Body weight; Body weight loss; Caloric Restriction; Clinical Nutrition; Epidemiology; Female; Gastrointestinal surgery; Health aspects; Homeostasis; Homeostasis - physiology; Humans; Hypocaloric diet; Insulin; Insulin - blood; Insulin Resistance; Internal Medicine; Liver; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medicine; Medicine & Public Health; Metabolic Diseases; Methods; Middle Aged; Multiple regression analysis; Muscles; NMR; Nuclear magnetic resonance; Nutrient deficiency; Obesity - blood; Obesity - diagnostic imaging; Obesity - therapy; original-article; Plasma; Postoperative Period; Public Health; Skeletal muscle; Weight control; Weight loss; Weight Loss - physiology; Whole Body Imaging - methods; Young Adult
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/ejcn.2016.189

Background/Objectives: We assessed the effect of weight loss-associated changes in detailed body composition on plasma insulin levels and homeostatic model assessment (HOMA) index to calculate the magnitude of reduction in different adipose tissue depots required to improve insulin sensitivity. SubjectS/Methods: A total of 50 subjects aged 20–69 years were studied. The participants were compiled from low-calorie diet interventions and bariatric surgery and differed in their baseline body mass index (BMI; range 21.6–54.4 kg/m 2 ) and degree of weight losses (range −3.3 to −56.9 kg). Detailed body composition and liver fat were measured using whole-body magnetic resonance imaging (MRI). Insulin resistance was assessed by HOMA. Results: Mean body weight decreased by −16.0±13.6 kg. Significant changes were observed in total adipose tissue (TAT MRI , range −0.5 to −36.0 kg), total subcutaneous adipose tissue (SAT MRI ), visceral adipose tissue (VAT MRI ), skeletal muscle, liver fat, plasma insulin levels and HOMA. Decreases in insulin and HOMA were correlated with reductions in TAT MRI , SAT MRI , VAT MRI (just with HOMA) and liver fat. Losses of 2.9 and 6.5 kg body weight, 2.0 and 5.0 kg TAT MRI as well as 1.6 and 6% liver fat were required to decrease plasma insulin levels by 1 μU/ml and HOMA adjusted for baseline HOMA by 1 point. Multiple regression analysis showed that baseline liver fat and changes in liver fat explained 49.7% and 55.1% of the variance in weight loss-associated changes in plasma insulin and HOMA, respectively. Conclusions: Decreases of adipose tissues and liver fat are the major determinants of reduction in plasma insulin levels and improvement in HOMA index.