Relationship Between Leukoaraiosis And Transient Ischemic Attack

[Objective]Leukoaraiosis is a common finding on cerebral magnetic resonance imaging(MRI).Increasing evidences support that the incidence of leukoaraiosis is high and severe in ischemic stroke,leukoaraiosis is independent risk factor of stroke incidence and strongly associates with stroke condition,progress,treatment and prognosis.However,the association of leukoaraiosis with transient ischemic attack is less well established.Transient ischemic attack is nerological emergency and relates with higher risk for future fatal or disabling vascular events.The aim of this study was to determine the clinical significance of leukoaraiosis in patients with transient ischemic attack,providing evidence for individualized treatment.[Methods]First-ever TIA inpatients between August 2010 to December 2015 were consecutively recruited within 48 hours of symptom onset.Brain MRIs were obtained to evaluate the presence of leukoaraiosis and determine volumes via continuous quantification using a semiautomatic image display program(MRIcro)software.Leukoaraiosis volumes were normalized to intracranial size and set as categorical variables using quartiles.Clinical data of these patients were collected.Generally,patients were prescribed with antithrombotics,statins,and treatment of vascular risk factors.Recurrent vascular events within one year of transient ischemic attack onset were assessed with follow-up.Statistically significant variables for this model were chosen at the univariable analysis to multivariate logistic regression and values of P<0.05 were considered statistically significant.Risk factors of the presence and severity of leukoaraiosis,and association between leukoaraiosis and vascular events were both determined.[Results](1)A total of 181 patients with transient ischemic attack were enrolled in our study.Leukoaraiosis was identified in 104 transient ischemic attack patients(57.5%)by MRI.In univariate analyses patients with leukoaraiosis were significantly older,more often had the history of hypertension,hyperlipidemia,higher ABCD2 score and silent brain infarction than those without leukoaraiosis.Between patients with and without leukoaraiosis there was no difference in gender,history of diabetes mellitus,smoking current,atrial fibrillation,coronary artery disease,clinical manifestation,symptom duration of TIA and lesion location.Multivariate logistic analysis showed that age(OR,1.12;95%CI,1.08-1.17;P=0.000)and hypertension(OR,2.11;95%CI,1.06-4.21;P=0.034)were strong risk factors of the presence of leukoaraiosis.(2)Normalized leukoaraiosis volumes ranges from 0.95 to 49.13 mL with median 5.00 mL.According to quartile of leukoaraiosis volume,increasing age(OR,1.07;95%CI,1.03-1.11;P=0.001)and hypertension(OR,2.21;95%CI,1.06-4.60;P=0.034)remained independent risk factors for leukoaraiosis volumes in univariate and multivariate analyses.(3)Twenty-six vascular events(14.4%)occurred during one year follow-up.In univariate analyses,age,hypertension,diabetes mellitus,hyperlipidemia,ABCD2 score and leukoaraiosis were associated with an increased risk of recurrent vascular event.Mxultivariate logistic analysis showed that age(OR,1.05;95%CI,1.00-1.11;P=0.040),diabetes mellitus(OR,2.92;95%CI,1.13-7.57;P=0.027),hyperlipidemia(OR,4.19;95%Cl,1.60-11,03;P=0.004)and leukoaraiosis(OR,3.71;95%Cl,1.09-12.60;P=0.036)were significantly independent risk factors of vascular events.The incidence of vascular events in patients with leukoaraiosis was 21.15%(22/104)compared with 5.19%(4/77)in those without leukoaraiosis.Patients with leukoaraiosis had more than 3-fold higher vascular events incidence than those without leukoaraiosis(OR,3.71;95%CI,1.09-12.60;P=0.036).(4)Among patients with leukoaraiosis,leukoaraiosis volume and hyperlipidemia(OR,5.38;95%CI,1.73-16.79;P=0.004)were independent risk factors of vascular event.Furthermore,fourth quartile of leukoaraiosis volumes were correlated with much more vascular events compared to the first quartile(OR,26.97,P=0.009).[Conclusions]Leukoaraiosis frequently occurs in transient ischemic attack patients.Age and hypertension were strong risk factors of the presence and severity of leukoaraiosis.The presence and severity of leukoaraiosis is significantly associated with high recurrent vascular events over the 1-year follow-up,suggesting a predictive value for transient ischemic attack outcomes.Severe leukoaraiosis is associated with clinical outcomes.Thus,we should evaluate not only the presence but also severity of leukoaraiosis.Active treatment of modifiable risk factors of leukoaraiosis(eg,hypertensive)will delay the occurrence and progression and improve prognosis of transient ischemic attack.