White Matter Hyperintensities Successfully Differentiate Parkinson's Disease Patients with and without Cognitive Impairment (P06.050)

OBJECTIVE: To examine the relationship of white matter hyperintensities (WMH) and cognitive impairment in Parkinson9s Disease (PD). BACKGROUND: Cerebral WMH detected on magnetic resonance imaging (MRI) brain scans are associated with cognitive impairment in the elderly and in Alzheimer9s disease. Less is known, however, about the contributions of WMH to PD mild cognitive impairment (PD-MCI) and PD dementia (PDD). DESIGN/METHODS: 98 PD subjects underwent clinical and neuropsychological evaluations and MRI brain scans (1.5T GE Signa). A blinded rater measured WMH on FLAIR sequences using the Scheltens scale. Subjects were classified as cognitively normal (PD-NC), PD-MCI, or PDD using published Movement Disorder Society criteria for PD-MCI and PDD. RESULTS: PD-NC (n=29), PD-MCI (n=44), and PDD (n=25) subjects did not differ in age, education, or vascular risk factors. Demented subjects had significantly longer PD duration and worse motor function. Total WMH scores differed among the cognitive groups (p=0.01) with significantly greater WMH burden in PDD compared to PD-NC subjects. Cerebral localization of WMH differed among the cognitive groups, with respect to periventricular and deep WMH (p=0.005 and p=0.03, respectively) but not basal ganglia or infratentorial regions. Periventricular WMH load was greatest in PDD, followed by PD-MCI, and least in PD-NC subjects, thereby differentiating PDD from PD-NC subjects (p=0.01) and PD-MCI from PD-NC subjects (p=0.02). Additionally, deep WMH were significantly greater in PDD compared to PD-NC subjects (p=0.02). Specifically, deep WMH located in the parietal lobe, differed among the cognitive groups (p=0.01), whereas other lobar regions did not. Moreover, the parietal lobe WMH distinguished PDD from PD-NC subjects (p=0.01) and PD-MCI from PD-NC subjects (p=0.02). CONCLUSIONS: Increased WMH burden in PD is associated with worse cognitive status, regardless of age or vascular risk factors. Periventricular and deep WMH, especially in the parietal lobe, differentiate the cognitive groups, and thus, may serve as markers of cognitive decline in PD. Supported by: K23NS060949, Parkinson9s Disease Foundation. Disclosure: Dr. Goldman has received personal compensation for activities with American Academy of Neurology, Movement Disorder Society, Johns Hopkins Dystonia and Spasticity Practicum, and Teva. Dr. Goldman has received research support from NIH/NINDS and the Parkinson9s Disease Foundation. Dr. Ebersole has nothing to disclose. Dr. Bernard has received research support from the Parkinson9s Disease Foundation. Dr. Ouyang has nothing to disclose. Dr. Goetz has received personal compensation for activities with Addex Pharma SA, Asubio, Biovail Technologies, Boston Scientific, Cleveland Medical Devices, Decision Resources, Dixon Group, ICON Clinical Research, Impax Pharmaceuticals, and Ingenix. Dr. Goetz has received personal compensation in an editorial capacity from the Movement Disorder Society, and the American Academy of Neurology. Dr. Goetz has received research support from Michael J. Fox Foundation and the Parkisnon9s Disease Foundation. Dr. DeToledo-Morrell has nothing to disclose. Dr. Stebbins has received personal compensation for activities with Impax, Ceregene, Inc., Biovail Technologies, Ltd., Santhera Pharmaceuticals, and Ingenix Pharmaceutical Services. Dr. Stebbins has received research support from the National Institutes of Health, American Cancer Society, Michael J. Fox Foundation for Parkinson Research, and Fragile-X Foundation.