Kidney function is associated with severity of white matter hyperintensity in patients with acute ischemic stroke/TIA

Previous studies suggested the potential interactions between cerebrovascular diseases and impaired renal function. However, the relationship between renal function and white matter hyperintensity (WMH), marker of cerebral small vessel disease, in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA) remains unknown.

We consecutively enrolled 1632 subjects with AIS or TIA who underwent brain MRI for this analysis. The severity of WMH in both of periventricular (PVH) and deep subcortical white matter (SDWMH) was evaluated using Fazekas scale. Estimated glomerular filtration rate (eGFR) was calculated by the equation of the Modification Diet for Renal Disease. Multinomial logistic regression was performed to evaluate the association between the severity of WMH and eGFR.

Advanced age and hypertension were independently associated with the severity of both PVH and SDWMH (all p < 0.001). There is a significantly inverse association between eGFR and PVH. Patients having each 30 ml/min/1.73 m² increase in eGFR was associated with 75 % of risk of having degree 3 of WMH in periventricular areas compared with degree 0 (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, OR = 0.93, 95 % CI0.75-1.14).

Our study demonstrates that renal dysfunction (eGFR) is independently associated with the severity of PVH but not SDWMH in patients with acute ischemic stroke. This results highlighted different pathological mechanism and risk factors of PVH and SDWMH.