Introduction: Renal function impairment is characterized by glomerular endothelial dysfunction and lipohyalinosis, both of which are typical features of cerebral small vessel diseases(CSVD). We thus presume that renal function might be associated with silent CSVD-related MRI changes including white matter hyperintensity (WMH), lacune and microbleeds, which was supported by previous findings observed from the individuals without stroke. However, the relationship between renal function and WMH in patients with acute ischemic stroke or transcient ischemic stroke (AIS/TIA) remains unclear. Thus we aim to explore the potential risk factors of WMH in patients with AIS/TIA, especially the association between renal function and WMH located in both periventricular and deep area.
Methods: A total of 1632 patients having an MRI examination were enrolled from SMART cohort for this analysis.The severity of WMH in both periventricular(PVH) and deep subcortical area(SDWMH) was evaluated using Fazekas scale. Estimated glomerular filtration rate(eGFR) was calculated by the equation of the Modification Diet for Renal Disease modified by the Chinese coefficient: eGFR(ml/min/1.73m2)=186хserum creatinine(exp[-1.154])хage(exp[-0.203])х1.233х0.742(if female).Multinomial logistic regression, adjusting for age, gender and vascular risk factors was performed to evaluate the association between the severity of WMH and eGFR.
Results: Advanced age and hypertension were independently associated with the severity of PVH and SDWMH (all p<0.001). Adjusting for age, gender and hypertension, the severity of PVH was found to be inversely related to eGFR. Each 30 ml/min/1.73m2 increase in eGFR was related to a lower risk of having degree 3 of WMH in periventricular areas, (p=0.04, OR=0.75, 95%CI 0.61-0.92). However this inverse association was not found between eGFR and SDWMH(P=0.50).
Conclusion: Our study demonstrates that renal dysfunction is independently associated with the severity of PVH but not SDWMH in patients with acute ischemic stroke. This result highlights different risk factors and mechanisms involved in the pathogenesis of PVH and SDWMH.