Objective: The first objective of this work was to report the prevalence of Parkinson’s disease (PD) cognitive impairment in three ethnicities from the East London PD project. The second objective was to compare the performance of screening tests in each ethnicity to the gold-standard assessment – a multidisciplinary team consensus.
Background: PD dementia (PDD) is one of the most feared aspects of PD. Research continues to focus disproportionately on White, well-educated, affluent patients1. It is unclear what the burden of PDD is in underrepresented populations. It is not known which PDD screening tool is the most culturally fair instrument.
Method: Patients with PD from the Royal London Hospital were recruited to the East London PD project2 – a case-control study which captures the clinical phenotype, genotype and biomarker characteristics. The multidisciplinary meeting was used to classify patients in PDD, mild cognitive impairment (PDMCI), and normal cognition (PDNC). This included demographics, comorbidities, education, mood and validated cognitive assessments. Screening instruments used were the Montreal cognitive assessment, MoCA, with a reliability decision, the clinical dementia rating scale, CDR and the Rowland universal dementia assessment scale, RUDAS.
Results: In the East London PD study 176 patients were examined with the cognitive protocol. After excluding patients with unreliable or partly absent cognitive scores, we included for analysis: 58 White, 43 South Asian, and 7 Black patients. The prevalence of PDD was 22% for White, 21% for South Asian and 14% for Black patients. PDMCI prevalence was 12% for White, 40% for South Asian, and 43% for Black patients. ROC curves of MoCA, CDR and RUDAS for PDD diagnosis were as follows: White (0.99, 0.99, 0.99), South Asian (0.98, 1, 0.96) patients. Similarly, for PDMCI, the AUCs were 0.93, 0.92, 0.84 in White, and 0.95, 0.89, 0.85 for South Asian patients. Black patients were excluded from ROC analysis due to low sample size.
Conclusion: Our study identified similar PDD prevalence in South Asian, Black and White patients. It also showed that MoCA, with a reliability measure, and CDR are more reliable cognitive tests than RUDAS, compared to the gold-standard. More work is needed to replicate these findings in other underrepresented groups.
References: 1. Gallagher, J. et al. Long-Term Dementia Risk in Parkinson Disease. Neurology 103, e209699 (2024).
2. Zirra, A. et al. The East London Parkinson’s Disease Project – A case-control study in a diverse population. medRxiv 2024.11.24.24317730 (2024) doi:10.1101/2024.11.24.24317730
To cite this abstract in AMA style:
A. Zirra, KC. Dey, E. Camboe, E. Bhadra, T. Haque, S. Waters, DA. Gallagher, C. Budu, B. Huxford, C. Simonet, C. Edwards, S. Ali, R. Weil, N. Mukadam, AJ. Lees, T. Boyle, MT. Perinan, CR. Marshall, AJ. Noyce. The East London Parkinson Disease Project: cultural fairness of common cognitive screening tests [abstract]. Mov Disord. 2025; 40 (suppl 1). https://www.mdsabstracts.org/abstract/the-east-london-parkinson-disease-project-cultural-fairness-of-common-cognitive-screening-tests/. Accessed October 5, 2025.« Back to 2025 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/the-east-london-parkinson-disease-project-cultural-fairness-of-common-cognitive-screening-tests/