Interpretable Machine Learning Models for Motor Fluctuations in Parkinson’s Disease with Cross-Cohort Analysis#
Authors#
Rebecca Ting Jiin Loo, Lukas Pavelka, Enrico Glaab
Abstract#
Background:#
Motor fluctuations are significant complications of long-term levodopa therapy in Parkinson’s disease, impairing motor functions and quality of life. Effective management strategies are needed to improve patient outcomes.
Objectives:#
This study uses machine learning on single and multi-cohort analyses to identify key risk factors for motor fluctuations in Parkinson’s disease, explore their interactions, and understand their contributions to this complication variability.
Methods:#
We applied interpretable machine learning techniques to clinical data from three independent longitudinal Parkinson’s disease cohorts: LuxPARK (n=395), PPMI (n=485), and ICEBERG (n=116). Cross-cohort prognostic models were developed to identify potential predictors of motor fluctuations. We used cross-validation to evaluate cohort-specific and shared predictive factors, model performance, stability, clinical utility, and calibration.
Results:#
Single- and multi-cohort analyses demonstrated the effectiveness of predictive models, identifying significant baseline clinical predictors for motor fluctuations. Positively correlated predictors included Hoehn & Yahr stage, MDS-UPDRS Parts I and II, bradykinesia, freezing, axial symptoms, and rigidity. Motor fluctuations risk was inversely associated with tremors, late onset of PD, and visuospatial abilities. Cross-cohort analyses showed higher stability than single-cohort analyses, mitigating cohort-specific bias and enhancing model robustness. The prognostic models exhibited substantial clinical utility and calibration, with reliable predictions closely aligning with observed outcomes.
Conclusions:#
This study presents interpretable machine learning models for motor fluctuations prognosis, demonstrating significant predictive capabilities in cross-cohort analyses despite differences between cohorts. Optimized predictive models can improve Parkinson’s disease management and inform clinical decision-making, ultimately improving patient outcomes.
Keywords: Motor fluctuations; Machine learning; Cross-cohort analysis; Longitudinal cohorts; Predictive modeling
Data availability#
The LuxPARK clinical dataset used in this study was obtained from the National Centre of Excellence in Research on Parkinson’s Disease (NCER-PD). The dataset for this manuscript is not publicly available as it is linked to the Luxembourg Parkinson’s Study and its internal regulations. Any requests for accessing the dataset can be directed to request.ncer-pd@uni.lu.
Data used in the preparation of this article were obtained on January 11, 2023, from the Parkinson’s Progression Markers Initiative (PPMI) database (www.ppmi-info.org/data/, RRID:SCR 006431). For up-to-date information on the study, please visit the PPMI website (www.ppmi-info.org).
Data from the ICEBERG cohort analyzed during this study is available from the corresponding study group (jean-christophe.corvol@aphp.fr, marie.vidailhet@aphp.fr).
Source code availability#
The source code used to produce the result is available at https://gitlab.com/uniluxembourg/lcsb/biomedical-data-science/bds/ml-motor-fluctuations.