Effects of Dopamine Cell Implants on Cognition in Parkinson's Patients

Abstract:
Abstract: This research studied the safety and efficacy of embryonic mesencephalic dopamine cell implants into the putamen of patients with advanced Parkinson's disease. Neuropsychological tests assessing orientation, attention, language, verbal and visual memory, abstract reasoning, executive function, visuospatial and construction abilities were administered prior to and one year following surgery. Subjects were forty patients (19f, 21m; age 34-75) with idiopathic Parkinson's disease of at least seven years' duration (mean 13.8 yrs). Age-stratified subjects (Young < 60 years; Elders 60 years and over) were randomly assigned to tissue implants or sham craniotomies in a double blind design. Treatment groups did not differ significantly on education or intellectual estimate. There were no significant differences between treatment groups on any of the neuropsychological change scores (follow-up minus baseline scores) for either age group. In real surgery patients, there were no significant correlations of neuropsychological change scores with a measure of cell growth (ratio of putamen to occipital uptake of [18F]fluoro-L-dopa). These results reveal that surgery did not adversely affect cognition, and the implants had no significant effect on cognition after one year.