Objective: To determine the association between demographic and cognitive features and subsequent progression of cognitive symptoms in Parkinson’s disease (PD).

Background: Most patients diagnosed with PD will eventually be diagnosed with mild cognitive impairment (PD-MCI) or dementia (PDD). Identification of a specific cognitive pattern or set of demographic features that predicts the progression of cognitive impairment could have meaningful implications for treatment planning and clinical management for patients with PD.

Methods: Longitudinal clinical and detailed cognitive data were available for 553 participants in the Pacific Northwest Udall Center of Excellence Clinical Consortium who met UK Brain Bank criteria for PD (mean follow up time = 2.7 years). To determine the association between baseline variables and subsequent progression of cognitive symptoms, separate logistic regression models were run for conversion from no cognitive impairment to PD-MCI and from PD-MCI to PDD. Model 1 included age, sex, education, disease duration, site, length of follow-up, and genetic status (GBA and APOE); model 2 added all cognitive variables. 

Results: Conversion from PD-MCI to PDD was associated with immediate verbal recall, processing speed, working memory, semantic verbal fluency, and male sex. Prediction of conversion from baseline PD-MCI to PDD was improved when cognitive scores were included as compared to the demographic-only model (area under the curve [AUC] 0.72 vs. 0.84, p<0.001). Among those who converted from no cognitive impairment to PD-MCI, male sex was the only significant baseline predictor of subsequent conversion (OR=4.05 95% CI 1.44-11.42, p<0.01); the addition of cognitive variables did not significantly improve the predictive value of the model (AUC 0.72 vs. 0.78). Despite longer disease duration among females, males were significantly more likely to progressively worsen in terms of their cognitive status. 

Conclusions: Cognitive test scores that largely measure executive functions predict conversion from PD-MCI to PDD over and above baseline demographic factors, suggesting that clinicians should pay special attention to changes that reflect these important cognitive features. Further exploration into potential mechanisms that underlie the relationship between male sex and progression of cognitive impairment will be critical for identification of future individualized interventions.  

« Back to 2017 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/cognitive-and-demographic-predictors-of-progression-to-mci-and-dementia-in-parkinsons-disease/