White Matter Abnormalities in Lacunar Stroke Patients
Background White matter abnormalities (WMA) on CT and MRI are commonly present in patients with cerebrovascular disease, especially in those with lacunar stroke. The underlying mechanism of WMA is still unclear, however an ischemic origin is postulated. Both lacunar stroke and WMA are mainly due to abnormalities of the small penetrating arteries. Objective To characterize the prevalence and severity of WMA in lacunar stroke patients and correlate them with vascular risk factors. Patients and Methods FLAIR MRI images of lacunar stroke patients in the NINDS funded Secondary Prevention of Small Subcortical Stroke (SPS3) pilot trial were included. Two neuroradiologists, blinded to clinical data, quantitated WMA using the European Task Force on Age Related White Matter Changes (ARWMC) and Fazekas scales. Results The first twenty-two patients entered in the study were included for this initial analysis: Mean age: 57 years, 50% females. The baseline characteristics and major vascular risk factors were similar in patients with mild WMA and in those with severe WMA (ARWMC 7+): mean age (59 vs 55 years) diabetes (64 vs 63%), hypertension (86 vs 88%) and smoking (71 vs 76%). Severity and distribution (periventricular and subcortical) of WMA showed similar distribution of risk factors. Severe WMA were more often present in Mexican-American patients (88 vs 46% p=0.09). Total number of lacunar infarcts correlated with severity of WMA (correlation coefficient 0.5, p=0.01). Conclusions Unexpectedly, severity of WMAs did not correlate with risk factors in these survivors of lacunar stroke, but did correlate with the number of lacunes. Our results support a common pathogenisis of lacunar infarcts and WMAs. These preliminary analyses will be extended as recruitment continues.