Category: Parkinson's Disease: Neuroimaging
Objective: The aim of the current study was to determine whether there are longitudinal differences in dopaminergic denervation of striatal sub-regions [signal reduction in 123I-FP-CIT SPECT] in Parkinson’s disease (PD) patients according to their olfactory competence during the initial disease stage.
Background: Dopaminergic degeneration in PD patients has been reported to correlate with various non-motor symptoms including olfaction deficits.
Method: 123I-FP-CIT SPECT imaging was acquired at Parkinson’s Progression Markers Initiative (PPMI) imaging centers using a uniform protocol and sent to the imaging core for calculation of striatal binding ratios. Longitudinal measurements included binding ratios in each striatal sub-region during screening visit and Year-1 , -2 and -4 visits. Data from the PPMI database of de novo PD patients scoring within the lowest quartile in University of Pennsylvania Smell Identification Test (UPSIT) were compared to those scoring within the highest quartile using age and sex as covariates. Aforementioned imaging and olfaction data were downloaded from the PPMI database (www.ppmi-info.org/data).
Results: Longitudinal striatal binding ratios in all striatal sub-regions [contralateral (p<0.001) and ipsilateral (p=0.005) putamen and contralateral (p=0.009) and ipsilateral (p=0.017) caudate] were lower in PD patients with inferior baseline UPSIT scores (lower quartile) as compared to those with superior UPSIT scores. The rate of signal decline was similar between the two groups for all striatal sub-regions with the exception of ipsilateral putamen.
Conclusion: Poor baseline olfactory function in de novo PD is associated with long-term dopaminergic denervation in striatal sub-regions. These results are supportive of a more malignant disease in terms of dopaminergic degeneration in PD patients with lower scores in olfactory testing during the initial stages of the disease.
This study was funded by Michael J.Fox Foundation as a part of PPMI Study.
To cite this abstract in AMA style:
C. Koros, A-M. Simitsi, N. Papagiannakis, A. Prentakis, A. Bougea, D. Papadimitriou, R. Antonelou, I. Pachi, E. Angelopoulou, E. Stanitsa, I. Beratis, S. Papageorgiou, M. Stamelou, X. Trapali, L. Stefanis. BASELINE OLFACTION TESTING IN PARKINSON’S DISEASE PATIENTS IS CORRELATED WITH LONG-TERM DOPAMINERGIC DENERVATION IN STRIATAL SUB-REGIONS: LONGITUDINAL DATA FROM THE PPMI STUDY. [abstract]. Mov Disord. 2021; 36 (suppl 1). https://www.mdsabstracts.org/abstract/baseline-olfaction-testing-in-parkinsons-disease-patients-is-correlated-with-long-term-dopaminergic-denervation-in-striatal-sub-regions-longitudinal-data-from-the-ppmi-study/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2021
MDS Abstracts - https://www.mdsabstracts.org/abstract/baseline-olfaction-testing-in-parkinsons-disease-patients-is-correlated-with-long-term-dopaminergic-denervation-in-striatal-sub-regions-longitudinal-data-from-the-ppmi-study/