The Study On Clinical And Imaging Features Of Ischemic Stroke In Young Adults

BackgroudsStroke is a major cerebrovascular disease threatening human health and life with high morbidity,disability and mortality.Recently,incidence of stroke in young adults increases gradually,bringing a heavy socio-economic burden,of which ischemic stroke is the most common one.Investigations on risk factors,etiology and prognosis of ischemic stroke in young adults may help prevent the damage.ObjectivesAim to investigate the demographic characteristics,potential risk factors,pathogenesis and predictors of prognosis of young adults with ischemic stroke,on the basis of analysis of clinical and imaging data.Then some preventive or therapeutic methods may be suggested.Methods(1)We retrospectively analyze clinical characters(including name,sex,age,previous history of stroke or transient ischemic attack,diabetes,ischemic heart disease,hyperlipidemia,hypertension,history of smoking,family history of cardiovascular disease)of young patients with acute ischemic stroke diagnosed by DWI from July 2014 to July 2016.We investigate features of risk factors of the patients,and compared them with that of older patients reported previously.(2)According to the location of infarction,all patients were divided into three groups:anterior circulation infarcts(ACI),posterior circulation infarcts(PCI)and anterior and posterior circulation infarcts(APCI).ASPECT score and DWI score were acquired from DWI of patients in ACI and PCI respectively,and the association with prognosis was assessed.(3)The association between ASPECT score and NIHSS and NII of patients in ACI,and between DWI score and NIHSS and NII in PCI were assessed.(4)According to the location of infarction on DWI and stenosis of ipsilateral MCA,patients with infarction in MCA territory were divided into three groups:branch occlusion disease(BOD),non-branch occlusion disease(non-BOD)and small artery disease(SAD).We compared risk factors,imaging features and short-term prognosis among these groups.Results(1)A total of 449 patients with acute ischemic.stroke were included in this study,of which 414 patients were available due to complete clinical and imaging data.(2)The average age was 48.5 years old,whreas patients of 46-54 years old accounting for 76.1%of the total number.Few patients younger than 35 years old were hospitalized.(3)More than 40 percent of patients reported a history of smoking.Patients with history of diabetes,hypertension and family cardiocerebrovascular disease are common.Hypertension is less common in young patients than in older one(24.7%vs 72.2%,p=0.000),while diabetes is more common in young patients than in older one(31.4%vs 22.8%,p=0.023).(4)Most ischemic stroke in young adults are attributed to large-artery atherosclerosis or small-artery disease(37.2%and 41.1%of total,respectively).Twelve patients are classified into cardioembolism,and 30 patients are classified into other etiology,including moyamoya disease,vasculitis and dissection.(5)Median of baseline NIHSS score is 3,suggesting a mild neurological deficit,and 72.5 percent of patients had a favourable prognosis.(6)NIHSS score and mRS score of patients on discharge in APCI is significally higher than in ACI and PCI(p=0.005,p=0.000,respectively).NIHSS score and mRS score of patients on discharge in PCI is significally higher than in ACI(p=0.016,p=0.008,respectively).N? of patients in PCI is significally higher than in ACI(median 0.5 vs 0.33,p=0.002).The proportion of patients with favorable prognosis in ACI and PCI is significally different(70%vs 83.1%,p=0.002).Only 38.1 percent of patients in APCI had a favorable prognosis,which is significally lower than the two goups mentioned above.(7)DWI score in PCI is significally associated with baseline NIHSS(r=0.331,p=0.000);ASPECT score in ACI is also significally associated with baseline NIHSS(r=-0.505,p=0.000).There is no association between N? and DWI score or ASPECT score.(8)A low ASPECT score suggests unfavorable outcome of patients in ACI(OR=1.483,p=0.000);A high DWI score suggests unfavorable outcome of patients in PCI(OR=0.336,p=0.000);A high baseline NIHSS score suggests unfavorable outcome of patients either in ACI or PCI.Both DWI score and NIHSS score are independent prognostic factors(p=0.003,p=0.000,respectively),while ASPECT score is not(p=0.348).(9)No difference is found between baseline NIHSS score and mRS score in BOD and SAD,while both are significally lower than that in non-BOD(p=0.000,p=0.001,respectively).(10)Thirty nine patients(69.6%)in non-BOD shows severe stenosis(>70%)or occlusion.Comparatively,more mild stenosis(<50%)is found in BOD(p=0.00).(11)MCA stenosis in BOD locates more distal than that in non-BOD(S/M1,58%vs 40%,p=0.000).Patients in the.BOD group had more focal MCA stenoses than those in the non-BOD group(%stenosis/extent of stenosis,median[interquartile range]1.86[1.35-2.6]vs 2.9[2.0-5.0],p=0.002).Conclusions(1)Ischemic stroke is not uncommon in young people,most of which are male.The peak age is around 50 years.Few patients are younger than 35 years old.(2)It is common for young ischemic stroke patients having classic risk factors,including hypertension,diabetes,smoking and family history of cardio-cerebrovascular disease.So it is also important to control risk factors in young patients for secondary prevention.(3)Most young ischemic stroke patients are classified into large-artery atherosclerosis or small-artery disease.Rare causes include moyamoya disease,vaculitis and dissection.(4)Most young ischemic stroke patients have a favorable outcome.Although similar neurological deficits presented at admission,patients with PCI demonstrated better short-term improvement and had more favorable outcome than patients with APCI.(5)A high baseline NIHSS score suggests unfavorable outcome of patients.A low ASPECT score suggests unfavorable outcome of patients in ACI.A high DWI score suggests unfavorable outcome of patients in PCI.Both baseline NIHSS score and DWI score are independent prognostic factors.(6)Mild focal stenoses located in distal Ml segment might induce branch occlusion disease,which shares similar imaging features with SAD.These patients always have a favorable outcome.In contrary,severe stenoses located in proximal Ml segment may cause extensive infarction including cotex,which often associated with a poor prognosis.