Abdominal fat depots and their association with insulin resistance in patients with type 2 diabetes

• Published in: PloS one 2023-12, Vol.18 (12), p.e0295492-e0295492
• Main Authors: Garg, Umesh Kumar, Mathur, Nitish, Sahlot, Rahul, Tiwari, Pradeep, Sharma, Balram, Saxena, Aditya, Jainaw, Raj Kamal, Agarwal, Laxman, Gupta, Shalu, Mathur, Sandeep Kumar
• Format: Article
• Language: English
• Subjects: Abdomen; Abdominal Fat - diagnostic imaging; Abdominal Fat - metabolism; Adipose tissue; Adipose tissues; Automation; Blood pressure; Body fat; Body Mass Index; Care and treatment; Cholesterol; Complications and side effects; Correlation; Deposition; Dextrose; Diabetes; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 2 - metabolism; Females; Genotype & phenotype; Glucose; Health aspects; High density lipoprotein; Humans; Insulin; Insulin Resistance; Lipoproteins; Liver; Magnetic resonance imaging; Measurement; Metabolic disorders; Metabolic Syndrome; Pathophysiology; Phenotypes; Prevention; Quartiles; Risk factors; Software; Spleen; Statistical analysis; Triglycerides; Type 2 diabetes; Variance analysis
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0295492

Asian-Indians show thin fat phenotype, characterized by predominantly central deposition of excess fat. The roles of abdominal subcutaneous fat (SAT), intra-peritoneal adipose tissue, and fat depots surrounding the vital organs (IPAT-SV) and liver fat in insulin resistance (IR), type-2 diabetes (T2D) and metabolic syndrome (MetS) in this population are sparsely investigated. Assessment of liver fat, SAT and IPAT-SV by MRI in subjects with T2D and MetS; and to investigate its correlation with IR, specifically according to different quartiles of HOMA-IR. Eighty T2D and the equal number of age sex-matched normal glucose tolerant controls participated in this study. Abdominal SAT, IPAT-SV and liver fat were measured using MRI. IR was estimated by the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). T2D and MetS subjects have higher quantity liver fat and IPAT-SV fat than controls (P = 9 x 10-4 and 4 x 10-4 for T2D and 10-4 and 9 x 10-3 for MetS subjects respectively). MetS subjects also have higher SAT fat mass (P = 0.012), but not the BMI adjusted SAT fat mass (P = 0.48). Higher quartiles of HOMA-IR were associated with higher BMI, W:H ratio, waist circumference, and higher liver fat mass (ANOVA Test P = 0.020, 0.030, 2 x 10-6 and 3 x 10-3 respectively with F-values 3.35, 3.04, 8.82, 4.47 respectively). In T2D and MetS subjects, HOMA-IR showed a moderately strong correlation with liver fat (r = 0.467, P < 3 x 10-5 and r = 0.493, P < 10-7), but not with SAT fat and IPAT-SV. However, in MetS subjects IPAT-SV fat mass showed borderline correlation with IR (r = 0.241, P < 0.05), but not with the BMI adjusted IPAT-SV fat mass (r = 0.13, P = 0.26). In non-T2D and non-MetS subjects, no such correlation was seen. On analyzing the correlation between the three abdominal adipose compartment fat masses and IR according to its severity, the correlation with liver fat mass becomes stronger with increasing quartiles of HOMA-IR, and the strongest correlation is seen in the highest quartile (r = 0.59, P < 10-3). On the other hand, SAT fat mass tended to show an inverse relation with IR with borderline negative correlation in the highest quartile (r = -0.284, P < 0.05). IPAT-SV fat mass did not show any statistically significant correlation with HOMA-IR, but in the highest quartile it showed borderline, but statistically insignificant positive correlation (P = 0.07). In individuals suffering from T2D and MetS, IR shows a trend towards positive and borderline neg