Renal and Renal Sinus Fat Volumes as Quantified by Magnetic Resonance Imaging in Subjects with Prediabetes, Diabetes, and Normal Glucose Tolerance

Abstract

2Purpose: The aim of this study was to assess the volume of the respective kidney compartments with 3 particular interest in renal sinus fat as an early biomarker and to compare the distribution between 4 individuals with normal glucose levels and individuals with prediabetes and diabetes. 5 Material and Methods: The sample comprised N = 366 participants who were either normoglycemic 6 (N = 230), had prediabetes (N = 87) or diabetes (N =49), as determined by Oral Glucose Tolerance Test. 7 Other covariates were obtained by standardized measurements and interviews. Whole-body MR 8 measurements were performed on a 3 Tesla scanner. For assessment of the kidneys, a coronal T1w dual-9 echo Dixon and a coronal T2w single shot fast spin echo sequence were employed. Stepwise semi-10 automated segmentation of the kidneys on the Dixon-sequences was based on thresholding and 11 geometric assumptions generating volumes for the kidneys and sinus fat. Inter-and intra-reader 12 variability were determined on a subset of 40 subjects. Associations between glycemic status and renal 13 volumes were evaluated by linear regression models, adjusted for other potential confounding variables.14 Furthermore, the association of renal volumes with visceral adipose tissue was assessed by linear 15 regression models and Pearson's correlation coefficient. 16Results: Renal volume, renal sinus volume and renal sinus fat increased gradually from normoglycemic

Which Patients with Obesity Are at Risk for Renal Disease?

“…Particularly, renal sinus fat obstructs the blood and lymph outflow of the kidney increasing hydrostatic pressure. The increase of renal volume as well as renal sinus fat volume in prediabetic subjects is associated with visceral adipose tissue and with cardiovascular risk factors [30]. The observation that microalbuminuria and macroalbuminuria do not always precede the loss of renal function in type 2 diabetes has led to the hypothesis that additional factors may play a role in the progression of renal disease before the onset of proteinuria.…”

The Relationship between Perirenal Fat Thickness and Reduced Glomerular Filtration Rate in Patients with Type 2 Diabetes

“…Besides, perirenal fat is more active in energy metabolism and adipokine secretion compared with typical visceral fat [17,23]. Renal sinus fat has been proved to increase in patients with prediabetes and diabetes, and negatively associated with estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes mellitus (T2DM) [24,25]. Additionally, it has been proved that renal sinus fat was associated with an increased risk of CKD in general subjects through inflammatory signaling [26][27][28].…”

Kidney Segmentation in Renal Magnetic Resonance Imaging - Current Status and Prospects

“…The accuracy of whole kidney segmentation is better than the accuracy of its partitioning into the three components (Table 2). The algorithm of Will et al was further used in a study of quantifying renal and renal sinus fat volumes from DIXON MR scans [129]. Here, a total of 400 patients from cross sectional population study were included.…”