Correlation Of Parkinson’s Disease With Perivascular Gap Enlargement And Cognitive Impairment

Objective(s): Cognitive impairment is one of the most common clinical symptoms among the non-motor symptoms of Parkinson’s disease(PD),and cognitive dysfunction has a serious impact on the quality of life,disability,and mortality of PD patients.It can be divided into PD with mild cognitive impairment(PD-MCI)and PD dementia(PDD),and some studies have proposed that the annual conversion rate of PD-MCI progressing to PDD is about 11%.Therefore,early prediction and identification of Parkinson’s disease with cognitive impairment can help patients’ treatment,improve their quality of life in the later stages of the disease and reduce the burden of caregivers,and it is necessary to explore the clinical predictors of Parkinson’s disease with cognitive impairment.With the development of imaging technology in recent years,imaging markers of cerebral small vessel disease(CSVD),including microhemorrhage,luminal foci,brain atrophy,perivascular space(EPVS)and cerebral white matter hyperintensities(WMH),have been increasingly studied,and the study of their effects on cognitive function in PD is still in the exploratory stage.There is heterogeneity in the results of studies on the effects of EPVS and WMH on cognitive function in PD,and there is still no study on the effects of EPVS and WMH on PD-MCI.The purpose of this study is to investigate the effects of EPVS and WMH on PD-MCI and whether they can be used as clinical predictors of PD-MCI.Methods: Two hundred PD patients hospitalized in our hospital from April2021 to April 2022 were included,and the Montreal Cognitive Assessment Scale(MOCA)was used to assess the cognitive function status of patients,who were classified according to their education level as follows: elementary or illiterate(received 6 years and less or no education);middle or high school(received 6-12 years of education);bachelor’s degree and above(received 12 years or more of education).Based on the results of the corresponding Mo CA collected,patients were classified into two categories using predetermined diagnostic cut-offs: PD patients without cognitive impairment(PD-NCI)were defined as having a score >23;whereas PD patients with mild cognitive impairment(PD-MCI)were defined as having a score22-23 or a score <22 without functional impairment.All subjects were scanned with3 T MRI,and cranial MRI sequences of T1 WI,T2WI,FLAIR,and DWI were collected to create axial,coronal,and sagittal images,respectively,to observe the signal,number,area,width,and shape of the lesion,whether it was accompanied by other possible lesions,whether there was edema around the lesion,and whether there was a possible occupying effect.EPVS and WMH were evaluated according to the reporting criteria for vascular changes in neuroimaging criteria.General clinical information,disease duration,levodopa dose(LED),H-Y staging,Unified Parkinson’s Disease Rating Scale Part III(UPDRSIII),and the Simple Mental State Examination Scale(MMSE)were completed for all PD patients.Univariate and multivariate logistic regressions were used to analyze the relationship between EPVS,WMH,and clinical demographic characteristics and cognitive decline,and to explore independent risk factors for cognitive decline.In addition,five electronic databases were searched for relevant studies,and further meta-analysis was conducted to explore the association between EPVS and PD-MCI.Results: Compared to the PD-NCI group,the PD-MCI group had significantly older patients,older age at onset,longer duration of PD,more male patients and lower educational attainment.Cognitive dysfunction was more common in patients with mid-to late-stage PD(Hoehn-Yahr stage: stage 3-5)than in patients with early stage(Hoehn-Yahr stage: stage 1-2).Univariate logistic regression identified patients with severe EPVS in the basal ganglia region,severe WMH,advanced age,older age of onset,male,low education,long duration of PD,low triglycerides,low uric acid,and low MMSE scores as risk factors for PD-MCI.After adjusting for clinicodemographic(age,sex,age at PD onset,education,duration of PD disease,triglycerides,uric acid,and Hoehn-Yahr stage)risk factors in multivariate logistic regression models,low education level(OR 0.262,95% CI 0.084-0.824,P=0.022)and severe EPVS in the basal ganglia region(OR 3.373,95% CI 1.348-8.442,P=0.009)remained as risk factors for cognitive dysfunction in PD.In addition,we performed a data search and found one relevant study,and a meta-analysis was performed jointly with our study,and the results of both studies showed that severe EPVS in the basal ganglia region was significantly associated with PD-MCI(P<0.001).Conclusion(s): Severe EPVS and low education level in the basal ganglia region are independent risk factors for PD-MCI,however,WMH is not an independent risk predictor for PD-MCI.Some clinical inspiration can be obtained from our findings that non-invasive examination of the severity of EPVS in the basal ganglia region by MRI may be a valuable indicator of cognitive decline in PD patients,and if PD patients have concomitant EPVS,screening for cognitive function should be enhanced and early intervention should be given to delay the onset of cognitive dysfunction in PD patients.