Renal sinus fat volume in type 2 diabetes mellitus is associated with glycated hemoglobin and metabolic risk factors

Aims: We aimed to compare renal sinus fat volume assessed by MRI between patients with type 2 diabetes and healthy volunteers, and investigate the association between renal sinus fat and metabolic traits. Methods: In this cross-sectional study, renal sinus fat and parenchyma volumes measured on abdominal MRI were compared between patients and controls using analysis of covariance. Associations of renal parameters with clinical characteristics were analyzed using linear regression analysis. Results: A total of 146 participants were enrolled, consisting of 95 type 2 diabetes patients (57.2 ± 8.8 years, 49.5% male) and 51 controls (54.0 ± 9.2 years, 43.1% male). Patients with diabetes demonstrated larger sinus fat volumes (15.4 ± 7.5 cm3 vs. 10.3 ± 7.1 cm3, p < 0.001) and sinus fat-parenchyma ratio than controls. In the total population, renal sinus fat was positively associated with HbA1c, abdominal VAT, cholesterol and triglycerides, after adjustment for age, sex, ethnicity and type 2 diabetes. In type 2 diabetes patients, increased sinus fat volume was significantly associated with urinary albumin-to-creatinine ratio. Conclusion: Renal sinus fat volume is positively associated with several metabolic risk factors including HbA1c level and urinary albumin-to-creatinine ratio in type 2 diabetes patients, indicating a potential role of renal sinus fat in the development of diabetic nephropathy. Future studies are needed to investigate whether sinus fat volume can serve as an early biomarker for diabetic nephropathy.