It remains unclear whether the difference between the estimated glomerular filtration rate based on cystatin C and creatinine (eGFRdiff) is associated with cerebral small vessel disease (CSVD). We investigated the correlation of eGFRdiff with SCVD and further evaluated the mediating role of blood pressure .

This prospective cohort study included 35,590 neurologically healthy participants at baseline (2006 to 2010) from the UK Biobank. eGFRdiff is divided into two indicators: absolute difference (eGFRabdiff) and ratio (eGFRrediff) based on the calculation between cystatin C and creatinine. CSVD was assessed by calculating white matter hyperintensity volume (WMHV) from T2-FLAIR brain MRI scans (conducted between 2014 and 2021), with values normalized to intracranial volume and log-transformed. Multiple linear regression models and mediation analysis was used to evaluate the associations of eGFRdiff with WMHV.

Participants with negative eGFRabdiff had higher WMHV (β = 0.07, 95% confidence interval [CL] = 0.04 ∼ 0.10), while participants with positive eGFRabdiff had smaller WMHV (β = -0.05, 95%CL = -0.09 ∼ -0.02), compared to midrange eGFRabdiff group. Meanwhile, participants with eGFRrediff ≤ 0.7 had higher WMHV compared with participants with eGFRrediff > 0.7 (β = 0.08, 95%CL = 0.01∼ 0.15) .In addition, hypertension mediated the associations between eGFRdiff and WMHV (12.6% ∼13.2%).

eGFRdiff was independently associated with WMHV. Our findings suggested that monitoring eGFRdiff has potential benefits in identifying the burden of CSVD in the general population in future.