Magnetic Resonance Imaging-Visible Perivascular Spaces in Basal Ganglia Predict Cognitive Decline in Parkinson's Disease

Background Growing evidence suggests an association between imaging biomarkers of small vessel disease and future cognitive decline in Parkinson's disease (PD). Recently, magnetic resonance imaging-visible perivascular space (PVS) has been considered as an imaging biomarker of small vessel disease, but its effect on cognitive decline in PD is yet to be investigated. Objective The objective of this study was to evaluate whether PVS can independently predict cognitive decline in PD. Methods A total of 271 PD patients were divided into 106 patients with intact cognition (PD-IC) and 165 patients with mild cognitive impairment (PD-MCI). After a mean follow-up of 5.0 +/- 2.3 years, 18 PD-IC patients showed cognitive decline to PD-MCI and 34 PD-MCI patients showed cognitive decline to dementia. PVS was rated in the basal ganglia (BG) and centrum semiovale using a 4-point visual scale and then classified as high (score >= 2) or low (score < 2) according to severity. Lacunes and white matter hyperintensity severity were also assessed. Independent risk factors for cognitive decline were investigated using multivariable logistic regression analysis. Results In all patients, higher BG-PVS and white matter hyperintensity severity, higher levodopa-equivalent dose, hypertension, and lower Mini-Mental State Examination score were independent positive predictors of future cognitive decline. In the PD-IC subgroup, higher BG-PVS severity, hypertension, and more severe depressive symptoms were predictors of cognitive conversion. In the PD-MCI subgroup, higher BG-PVS and white matter hyperintensity severity, and lower Mini-Mental State Examination score were predictors of cognitive decline. Conclusions BG-PVS may be a useful imaging marker for predicting cognitive decline in PD. (c) 2019 International Parkinson and Movement Disorder Society