title: Progression of small vessel disease correlates with cortical thinning in Parkinson's disease.
abstract: Cerebral small-vessel disease (SVD) is a risk factor for dementia in Parkinson's disease (PD), however the pathophysiological role of SVD in PD-dementia is unclear. We investigated the impact of baseline and progression of SVD on cortical thickness and the correlation to cognition.
  
  
  
  Seventy-three mild PD patients with baseline and follow-up structural MRI scans, serial clinical and neuropsychological assessments were studied. SVD included the load of white matter hyperintensities (WMH), lacunes and perivascular spaces (PVS). WMH progression was assessed using the modified Rotterdam Progression scale, while for lacunes and PVS, development of new lesions was considered as lesion progression. Patients were classified as having SVD-progression and SVD-no-progression based on the longitudinal changes in their SVD measures. Freesurfer was used to measure baseline and follow-up regional cortical thickness and subcortical volumes and correlated to cognitive performance.
  
  
  
  Fourteen patients were classified as SVD-progression and 59 as SVD-no-progression. Over 18 months, PD SVD-progression demonstrated significant cortical thinning in the left frontal and bilateral parietal regions with associated decline in memory, executive function, and motor functions. PD SVD-progression also had reduced volumes in the nucleus accumbens and amygdala at baseline and greater atrophy in the caudate nucleus over 18 months.
  
  
  
  The extent and progression of SVD is associated with focal cerebral atrophy and domain-specific cognitive dysfunction. Measures to retard SVD may be potentially useful in preventing dementia in PD.
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore.
authors.forename: Heidi
authors.initials: H
authors.lastname: Foo
authors.affiliation: Department of Psychiatry, University of Cambridge, UK.
authors.forename: Elijah
authors.initials: E
authors.lastname: Mak
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore.
authors.forename: Ting Ting
authors.initials: TT
authors.lastname: Yong
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore.
authors.forename: Ming-Ching
authors.initials: MC
authors.lastname: Wen
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore.
authors.forename: Russell Jude
authors.initials: RJ
authors.lastname: Chander
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore; Duke-NUS, Graduate Medical School, Singapore.
authors.forename: Wing Lok
authors.initials: WL
authors.lastname: Au
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore; Duke-NUS, Graduate Medical School, Singapore.
authors.forename: Louis
authors.initials: L
authors.lastname: Tan
authors.affiliation: Department of Neurology, National Neuroscience Institute, Singapore; Duke-NUS, Graduate Medical School, Singapore. Electronic address: Nagaendran_Kandiah@nni.com.sg.
authors.forename: Nagaendran
authors.initials: N
authors.lastname: Kandiah
mesh_terms: D000368:Aged; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D059345:Cerebral Small Vessel Diseases / Q000150:complications* / Q000000981:diagnostic imaging; D003072:Cognition Disorders / Q000209:etiology*; D018450:Disease Progression; D056344:Executive Function / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000473:pathology*; D018709:Statistics, Nonparametric
keywords: Cortical thinning; Neuroimaging; Parkinson’s disease; Small vessels cerebrovascular disease