Objective: To investigate whether the neuropsychological tests differ among participants with Parkinson’s disease (PD) presenting with the subjective cognitive complaint (PD-SCC) and PD with normal cognition (PD-NC) in the data from the Parkinson’s Progression Markers Initiative (PPMI) study.

Background: Recent studies have shown that PD-SCC is more likely to progress to PD with mild cognitive impairment (MCI), although PD-SCC is not consistently used in the PD-MCI classification. Hence it is important to understand whether the routine neuropsychological scores utilized in the identification of PD-MCI differ among PD-NC and PD-SCC.

Method: In this pilot study, we only selected those participants that were classified as PD-SCC at either visit and had a complete neuropsychological evaluation. As the control group, we selected age, sex, and years of education (YOE)-matched PD-NC participants that had a complete neuropsychological evaluation and remained stable at all visits. This procedure was applied to minimize heterogeneity in the clinical diagnosis of PD-NC. Since a lot of PD-NC participants in our list had a missing language component, we only considered four cognitive domains (Attention/Working Memory, Immediate Memory, Delayed Memory, and Visuospatial) in addition to global cognition (Montreal Cognitive Assessments – MoCA). We identified 16 PD-SCC participants (Age: 68±6 years (mean ± SD), 16±2 YOE, and 62.5% male) and 16 PD-NC participants (Age: 65±6 years, 17±2 YOE and 62.5% male). Statistical comparisons were conducted using non-parametric statistics using PALM in FSL, and the results were corrected for multiple comparisons. Only familywise error-corrected p-value (p_corr) <0.05 was considered significant. Of note, age, sex, YOE, and MoCA were considered variables of no interest, and their effects were regressed before statistical comparisons.

Results: We found that the PD-NC performed significantly (p_corr<0.05) better in the visuospatial domain. There were no statistically significant differences between any other domains between groups.

Conclusion: Our pilot analysis suggested that PD-SCC has a significantly compromised visuospatial domain and that this parameter could be explored further to identify progression to PD-MCI. Future analysis with an understanding of MRI correlates of these neuropsychological measures in PD-SCC and PD-NC groups is currently underway.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/does-cognitive-complaint-in-parkinsons-disease-reflect-in-neuropsychological-testing/