Decreased kidney function relates to progression of cerebral microbleeds in lacunar stroke patients

It is hypothesized that impaired kidney function and cerebral microbleeds represent microvascular damage in different organs. Several cross-sectional studies found impaired kidney function to be associated with the presence of cerebral microbleeds.

To further confirm the association between both small vessel diseases, we aimed to determine whether kidney function is related to progression of cerebral microbleeds in a longitudinal study design.

In 89 lacunar stroke patients, baseline brain magnetic resonance imaging (including gradient-echo images), baseline estimated glomerular filtration rate (eGFR), blood pressure measurements, and follow-up brain magnetic resonance imaging after two years were available. Presence of cerebral microbleeds on baseline and follow-up magnetic resonance imaging was scored visually. Cerebral microbleeds progression was defined as the presence of any new microbleed on follow-up magnetic resonance imaging. The association between cerebral microbleeds progression (dependent variable) and eGFR (independent variable) was assessed by logistic regression analysis.

Cerebral microbleeds progression was present in 17 patients (19.1%). Lower eGFR was associated with cerebral microbleeds progression (OR 1.55 per 10 ml/min/1.73 m(2) decrease, 95% CI 1.05-2.30, with correction for sex and age). After additional correction for baseline presence of cerebral microbleeds or correction for cardiovascular risk factors, including blood pressure, this result remained significant.

In this longitudinal study, we found an independent association between lower eGFR and cerebral microbleeds progression. Cerebral microbleeds and impaired kidney function are both seen as manifestations of microvascular organ damage and our findings further strengthen the association between both small vessel pathologies and also the assumption that small vessel disease could be considered a multisystem disorder.