Category: Rating Scales
Objective: To assess the change over time (1-2 years) on the Clinical Dementia Rating Sum of Boxes (CDR-SOB) in Parkinson’s disease (PD).
Background: The CDR-SOB is widely used to assess combined cognition and daily function in patients with Alzheimer’s disease (AD). The CDR-SOB could prove useful in evaluating PD patients with cognitive decline. Baseline evaluations of the CDR-SOB in PD patients displayed high internal consistency, as well as significant correlations between CDR-SOB scores and neuropsychological evaluations in both global and domain-specific scores. Longitudinal research is needed to further establish the validity of the CDR-SOB in assessing cognition and function in PD.
Method: Patients with idiopathic PD and their informants were re-administered the CDR-SOB 1-2 years after baseline in conjunction with a longitudinal. observational study. Evaluations involved global and domain-specific cognitive testing (DRS-2 and MoCA), and functional questionnaires (ADLi and PDAQ). Patients were given a consensus diagnosis of normal cognition (NC) or cognitive impairment (CI; MCI or dementia) by an expert panel concurrent with CDR-SOB administration.
Results: 55 participants (at baseline NC=28 and CI=27) completed a follow-up CDR-SOB (mean interval between administrations=20.70 months). The average total CDR-SOB score for the entire group at baseline was 2.12 (median=1.50, range=13.0), and the score was significantly worse in CI subgroup (p<0.001). There was a significant decline over time in global cognitive performance (DRS-2 [p=0.001] and MoCA [p<0.001]), but not in function or CDR-SOB score. In linear regression models change in DRS-2 and MoCA scores predicted change in CDR-SOB score over time (both p<0.05). However, in similar models there was no association between change in functional measures (ADLi and PDAQ) and change in CDR-SOB score over time.
Conclusion: The CDR-SOB does not decline in the medium-term compared with global cognitive testing in a cohort of PD patients with mixed cognitive abilities. The lack of decline in functional abilities over this time period may explain the lack of change in CDR-SOB scores, calling into question its utility as a composite cognition-function measure in Parkinson’s patients with predominantly NC or MCI.
To cite this abstract in AMA style:
J. Gallagher, J. Rick, S. Xie, E. Mamikonyan, B. Deck, S. Rudovsky, A. Chen-Plotkin, N. Dahodwala, J. Morley, J. Duda, J. Trojanowski, D. Weintraub. Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) in Parkinson’s Disease: Longitudinal Results [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/clinical-dementia-rating-scale-sum-of-boxes-cdr-sob-in-parkinsons-disease-longitudinal-results/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/clinical-dementia-rating-scale-sum-of-boxes-cdr-sob-in-parkinsons-disease-longitudinal-results/