MR Assessed Changes of Renal Sinus Fat in Response to Glucose Regulation in West European and South Asian Patients With Type 2 Diabetes

BackgroundEthnic differences in the progression and outcome of diabetic kidney disease (DKD) remain to be elucidated. MRI-quantified renal sinus fat volume could be a potential biomarker to help investigate the changes of DKD risk in response to glucose regulation.PurposeTo evaluate whether the effect of glucose-lowering treatment on renal sinus fat volume differed in West Europeans (WE) compared to South Asians (SA), and whether ethnic-related difference exists regarding the effect of liraglutide on renal sinus fat.Study TypeRetrospective.PopulationNinety-three patients with type 2 diabetes mellitus, including 47 WE (27 males) aged 59.3 +/- 6.5 years, and 46 SA (19 males) aged 54.4 +/- 9.8 years.Field Strength/Sequence3.0 T dual-echo fast gradient-echo pulse sequence using two-point Dixon technique with a phase-correction algorithm.AssessmentChanges of renal sinus fat volume were measured by a radiologist (LL) with 4-years' experience, and were compared between the two ethnic groups, together with glycemic level, metabolic risk factors and renal function. The effects of liraglutide were assessed.Statistical TestsNormality of the data was visually evaluated by histograms and Q-Q plots. Within-group and between-group differences were analyzed using paired t-tests and analysis of covariance. Associations were analyzed by person's correlation and multiple linear regression models.ResultsRenal sinus fat decreased in SA patients (Delta% = -7.6% +/- 14.8%), but increased in WE patients (Delta% = 5.0% +/- 13.1%), with a significant difference between the two ethnic groups. In the WE group, the increase of sinus fat volume was significant in the placebo subgroup (Delta% = 6.8% +/- 12.5%), in contrast to the nonsignificant increase in the liraglutide subgroup (Delta% = 3.0% +/- 13.8%, P = 0.444).Data ConclusionRenal sinus fat accumulation responds differently to glucose regulation, showing a reduction in SA patients in contrast to a persistent accumulation in WE patients. A trend of less accumulation of sinus fat in WE patients receiving liraglutide has been observed.Evidence Level4Technical EfficacyStage 4