Correlation Between Macrovascular Disease And Cerebral Small Vessel Disease

Part 1.The risk factors of arterial atherosclerosis,stiffness and dolichoectitia.Background and purpose:Most research on large-vessel disease emphasized the intima and endothelial portions of arteries,such as atherosclerosis,and less attentions were paid on arterial stiffness and dilation,which mainly involved arterial media.what’s more,scarce previous studies investigated risk factors of these large-vessel diseases in different vascular beds simultaneously.In a community-based study,we aim to investigate the association of conventional vascular risk factors and large-vessel diseases(atherosclerosis,arterial stiffness and dolichoectasia)in different vascular beds(aorta,carotid arteries and intracranial arteries).Methods:Participants were recruited from an ongoing community-based cohort in China.We used carotid intima-media thickness(IMT),carotid plaque and intracranial atherosclerotic stenosis(ICAS)to assess arterial atherosclerosis,and used brachial-ankle pulse wave velocity(baPWV)and carotid pulse wave velocity to assess arterial stiffness.We also used inter-adventitial diameter of common carotid artery(CCA-IAD),lumen diameter of basilar artery(BA)and internal carotid artery(ICA),bifurcation of BA,and laterality of BA to assess arterial dolicoectasia.Conventional vascular risk factors included age,sex,body mass index,systolic blood pressure,antihypertensive treatment,low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),triglyceride and homocysteine.Multivariable linear regression models and Logistic models were used to explore the association between conventional vascular risk factors and these arterial measurements.Results:A total of 1787 participants were included.The mean age was 56.4 years(SD,10.6).In multivariable regression,advanced age,higher systolic blood pressure,diabetes mellitus,higher LDL-C,lower HDL-C were independently associated with carotid IMT,carotid plaque and ICAS.Advanced age,increased systolic blood pressure and diabetes mellitus were associated with both baPWV and carotid PWV,but dyslipidemia was not significantly related to arterial stiffness.Conventional vascular risk factors accounted for 41.1%variance of baPWV,whereas only accounted for 19.8%variance of carotid PWV.Age,increased total intracranial volume(TIV)were associated with dilation of CCA,ICA and BA.Higher systolic blood pressure was related to larger inter-adventitial diameter of common carotid artery,whereas related to smaller lumen diameter of internal carotid artery.Additionally,diabetes mellitus was associated with narrowing of ICA and higher LDL-C and TG were associated with narrowing of BA.Basilar artery dolichoectasia(BADE)was unrelated to vascular risk factors other than age.Conventional risk factors accounted for 8%～42%variance of studied large-vessel structural and functional measurements.Conclusions:Age and hypertension were common risk factors of atherosclerosis,arterial stiffness and arterial dolichoectasia.Dyslipidemia was significantly associated with atherosclerosis,but not with arterial stiffness and dolichoectasia.Basilar artery dolichoectasia(BADE)was unrelated to vascular risk factors other than age.Conventional risk factors account for different variance of large-vessel diseases in different vascular beds.Part 2.The asscociation between large-vessel structural and functional characteristics and cerebral small vessel disease.Background and purpose:Structural and functional characteristics of large vessels were associated with cerebral small vessel disease(CSVD).Most previous studies only focused on the relationship of specific large-vessel characteristic to some imaging phenotypes of cerebral small vessel disease.In this study,we aim to investigate the association of both structural and functional characteristics of large vessels in different vascular bed with all established imaging markers of cerebral small vessel disease in a community-based cohort.Methods:Participants were recruited from an ongoing community-based cohort in China.We used carotid intima-media thickness(IMT),carotid plaque and intracranial atherosclerotic stenosis(ICAS)to assess arterial atherosclerosis,and used brachial-ankle pulse wave velocity(baPWV)and carotid pulse wave velocity to assess arterial stiffness.We also used inter-adventitial diameter of common carotid artery(CCA-IAD),lumen diameter of basilar artery(BA)and internal carotid artery(ICA),bifurcation of BA,and laterality of BA to assess arterial dolicoectasia.For assessment of cerebral small vessel disease burden,we visually rated lacunes,microbleeds,dilated perivascular spaces(PVS)and automatically segmented white matter hyperintensities(WMH).Brain parenchymal fraction(BPF)was used as an index of brain atrophy.Multivariable linear regression models and Logistic models were used to explore the association between large-vessel measurements and cerebral small vessel disease.Results:A total of 1323 participants completed cerebral MRI.The mean age was 55.5 years(SD,9.7)and 38,1%were men.The prevalence of lacunes,strictly lobar microbleeds,deep or infratentorial microbleeds,severe PVS in basal ganglion and white matter were 17.9%,5.2%,6.6%,13.4%,14.3%,respectively.The median WMH volume was 0.9ml(inter-quantile range,0.3-2.9)and mean BPF was 0.76(SD,0.03).Carotid plaque and intracranial atherosclerotic stenosis were associated with lacunes,WMH volume,and brain atrophy,but not with microbleeds and dilated PVS.Furthermore,the association of carotid plaque and intracranial atherosclerotic stenosis with brain atrophy were independent of lacunes and WMH.BaPWV was significantly associated with lacunes and WMH volume,whereas carotid stiffness was not related to cerebral small vessel disease.Intracranial arterial dolichoectasia was mainly associated with deep or infratentorial microbleeds and dilated PVS in basal ganglia.What’s more,increased inter-adventitial diameter of common carotid artery was significantly associated with lacunes,WMH volume,deep or infratentorial microbleeds and dilated PVS in basal ganglia,independent of vascular risk factors and carotid IMT.Conclusions:large-vessel structural and functional characteristics were associated with different imaging phenotype of cerebral small vessel disease.Atherosclerosis was associated with lacunes and WMH,while arterial dolichoectasia was associated with deep microbleeds and dilated PVS,indicating distinct underlying mechanisms.