Adiposity measures incorporating waist circumference, particularly waist-to-height ratio, are associated with renal sinus fat independent of BMI, while renal sinus fat relative to total kidney area predicts eGFR.
Key Findings
Results
Body Roundness Index (BRI), waist-to-height ratio (WHtR), and waist circumference showed the strongest associations with RSF in multivariable regression analyses adjusted for age, sex, and BMI.
Study included 74 individuals with severe obesity and 47 lean volunteers
Renal sinus fat (RSF) and RSF relative to total kidney area (RSF%) were assessed via MRI
Multivariable regression analyses were adjusted for age, sex, and BMI
Of the three strongest predictors, only WHtR was significantly associated with RSF%
Results
Both RSF and RSF% were inversely correlated with estimated glomerular filtration rate (eGFR) in univariate analyses, but only RSF% remained independently associated with eGFR in multivariate analysis.
Univariate analyses showed inverse correlations for both RSF and RSF% with eGFR
In multivariate analysis, RSF% but not RSF was independently associated with eGFR
This suggests RSF normalized to kidney size is the more relevant predictor of kidney function
Results
Post-bariatric surgery, changes in RSF correlated with changes in WHtR and BRI.
50 persons with obesity were re-evaluated 6 to 12 months after undergoing bariatric surgery
RSF change post-surgery correlated with changes in both WHtR and BRI
This longitudinal finding supports WHtR and BRI as dynamic markers of RSF change following weight loss intervention
Conclusions
RSF and RSF% offer complementary insights, with RSF showing stronger relationships with adiposity measures and RSF% predicting eGFR.
RSF exhibits a stronger relationship with adiposity measures including BRI, WHtR, and waist circumference
RSF% is the metric that independently predicts eGFR in multivariate analysis
Authors conclude both metrics should be considered in future studies
Results
Adiposity indices incorporating waist circumference are associated with RSF independent of BMI.
Associations of BRI, WHtR, and waist circumference with RSF remained significant after adjustment for BMI
This suggests these measures capture aspects of fat distribution relevant to RSF beyond overall body mass
The study design included a wide range of body sizes by combining 74 individuals with severe obesity and 47 lean volunteers
Moriconi D, Honka M, Saukko E, Moritz E, Latva-Rasku A, Dadson P, et al.. (2026). Waist-to-height ratio as a non-invasive marker of renal sinus fat: a MRI-based cohort study.. International journal of obesity (2005). https://doi.org/10.1038/s41366-025-01974-4