Differential Implications of Cerebral Hypoperfusion and Hyperperfusion in Parkinson's Disease

Abstract

BackgroundPatients with Parkinson&apos;s disease (PD) exhibit widespread brain perfusion changes. ObjectiveThis study investigated whether cerebral regions with hypoperfusion and hyperperfusion have differential effects on motor and cognitive symptoms in PD using early-phase F-18-N-(3-fluoropropyl)-2 & beta;-carboxymethoxy-3 & beta;-(4-iodophenyl) nortropane (F-18-FP-CIT) positron emission tomography (PET) scans. MethodsWe enrolled 394 patients with newly diagnosed PD who underwent dual-phase F-18-FP-CIT PET scans. Indices reflecting associated changes in regional cerebral hypoperfusion and hyperperfusion on early-phase F-18-FP-CIT PET scans were calculated as PD[hypo] and PD[hyper], respectively. The associations of PD[hypo] and PD[hyper] on motor and cognitive symptoms at baseline were assessed using multivariate linear regression. Also, Cox regression and linear mixed models were performed to investigate the effects of baseline PD[hypo] and PD[hyper] on longitudinal outcomes. ResultsThere was a weak correlation between PD[hypo] and PD[hyper] (& gamma; = -0.19, P < 0.001). PD[hypo] was associated with baseline Unified Parkinson&apos;s Disease Rating Scale Part III scores (& beta; = -1.02, P = 0.045), rapid increases in dopaminergic medications (& beta; = -18.02, P < 0.001), and a higher risk for developing freezing of gait (hazard ratio [HR] = 0.67, P = 0.019), whereas PD[hyper] was not associated. Regarding cognitive function, PD[hypo] was more relevant to the baseline cognitive performance levels of visuospatial, memory, and frontal/executive function than PD[hyper]. However, greater PD[hyper] was associated with future dementia conversion (HR = 1.43, P = 0.004), whereas PD[hypo] was not associated. ConclusionsThese findings suggest that PD[hypo] and PD[hyper] may differentially affect motor and cognitive functions in patients with PD. & COPY; 2023 International Parkinson and Movement Disorder Society.