Clinical data, Montreal Cognitive Assessment (MoCA), and Unified Parkinson’s Disease Rating Scale (UPDRS) scores (Mean ± SD).
DAT SPECT in Healthy Controls
DAT SPECT in Parkinson’s Disease at Baseline
VMAT2 in Parkinson’s Disease at Baseline
DAT SPECT (top and middle) and VMAT2 PET (bottom) baseline population average images superimposed on the T1-weighted MRI template.
The Specific Binding Ratio (SBR) data at baseline is plotted as the mean ± SEM for the striatum and substructures (putamen, caudate and pallidum). DAT SPECT was assessed in healthy controls (blue; N=37), and Parkinson’s disease (PD) participants (purple; N=134), VMAT2 was assessed in PD participants only (pink; N=15). Statistical significance comparison between the clinical phenotypes for DAT SPECT was analyzed by one-way ANOVA and Tukey's test for multiple comparisons. **** p<0.0001 applies to all the regions compared.
Data Sources
Data used in the preparation of this presentation were obtained from the Parkinson's Progression Markers Initiative (PPMI). PPMI was launched in 2010 and is conducted in the United States, Europe, Israel, and Australia. The study is sponsored by The Michael J. Fox Foundation for Parkinson’s Research and is made possible by restricted donations to the Foundation from a consortium of Parkinson’s drug development stakeholders. PPMI is led by Principal Investigator Ken Marek, MD, President and Senior Scientist of the Institute for Neurodegenerative Disease in New Haven, Connecticut. The primary goal of PPMI is to identify biological markers of Parkinson’s risk, onset and progression — critical tools for the development of new and better treatments — and to provide the broad research community a comprehensive, standardized, longitudinal data set and biosample library to speed breakthroughs and enable validation toward clinical application of new findings.
The Parkinson's disease data used for analysis was obtained from the Parkinson's Progression Markers Initiative database. A primary goal of PPMI is to identify biological markers of Parkinson’s disease risk, onset, and progression.
As outlined in the table, Healthy Control and Sporadic Parkinson’s Disease participants were included in the baseline analysis, while the follow-up longitudinal analysis was performed only on PD patients. The cohorts have slightly more male than female participants, with an average age of ~60 years. Participants in the PD group have significantly higher UPDRS scores and only slightly lower MoCA scores when compared to the Healthy Control participants.
The thresholded DAT SPECT images superimposed on the 3D T1-weighted MRI illustrate the reduction in the dopaminergic signal in the PD population at baseline compared to the healthy controls. In the grey matter masked VMAT2 PET images, one can note the higher resolution compared to DAT SPECT.
Quantitative regional analysis of the specific binding ratio (SBR) illustrates the significant reduction of signal apparent in the striatum and the sub-regions when comparing DAT SPECT in the PD population to the healthy controls. SBR derived from VMAT2 scans in the PD population is similar order to that observed in the DAT SPECT data.