Kidney function and cerebral small vessel disease in the general population

Background: Anatomic and hemodynamic similarities between renal and cerebral vessels suggest a tight link between kidney disease and brain disease. Although several distinct markers are used to identify subclinical kidney and brain disease, a comprehensive assessment of how these markers link damage at both end organs is lacking. Aim: To investigate whether measures of kidney function were associated with cerebral small vessel disease on MRI. Methods: In 2526 participants of the population-based Rotterdam Study, we measured urinary albumin-to-creatinine ratio, and estimated glomerular filtration rate based on serum creatinine and cystatin C. All participants underwent brain magnetic resonance imaging. We assessed presence of cerebral small vessel disease by calculating white matter lesion volumes and rating the presence of lacunes and cerebral microbleeds. We used multivariable linear and logistic regression to investigate the association between kidney function and cerebral small vessel disease. Results: Worse kidney function was consistently associated with a larger white matter lesion volume (mean difference per standard deviation increase in albumin-to-creatinine ratio: 0·09, 95% confidence interval 0·05; 0·12; per standard deviation decrease in creatinine-based estimated glomerular filtration rate: -0·04, 95% confidence interval -0·08;-0·01, and per standard deviation decrease in cystatin C-based estimated glomerular filtration rate: -0·09, 95% confidence interval -0·13;-0·05). Persons with higher albumin-to-creatinine ratio or lower cystatin C-based estimated glomerular filtration rate levels had a higher prevalence of lacunes (odds ratio per standard deviation increase in albumin-to-creatinine ratio: 1·24, 95% confidence interval 1·07; 1·43). Only participants in the highest quartile of albumin-to-creatinine ratio had a higher frequency of microbleeds compared to the lowest quartile. Conclusions: Worse kidney function is associated with cerebral small vessel disease. Of all measures of kidney function, in particular albumin-to-creatinine ratio is related to cerebral small vessel disease.