Cognitive decline after subthalamic deep brain stimulation in Parkinson’s disease is preceded by pre-surgery executive deficit: An observational longitudinal study

Bayesian multilevel models of long-term post-surgery cognitive decline after subthalamic nucleus deep brain stimulation (STN DBS) in Parkinson's disease (PD). Files include: (A) Models reported in the main text ("models with weakly informative priors" folder), (B) Models used for sensitivity analysis reported in supplemental materials ("models with flat priors" folder), (C) R scripts to calculate prior predictive check and generate Tables 5 and 6 from the main text ("R scripts" folder). The study investigated which pre-surgery cognitive profile characteristics are predictive of post-surgery cognitive decline in PD patients treated with STN DBS. Cognitive decline is a severe non-motor complication in PD that can significantly reduce benefits from STN DBS treatment. In the present study, we demonstrated that pre-surgery executive deficit can predict faster post-surgery decline in screening for dementia signs (according to Mattis Dementia Rating Scale, DRS-2). The sample size of this study was (respectable) 106 patients followed for 3-11 years after STN DBS surgery. Majority of patients had at least three assessments making it easier for us to fit multilevel models and enjoy some of their cool properties such as partial pooling. Since the study was a series of retrospective clinical observations, it is not ethically acceptable for us to publish patients' raw data. However, you, dear reader, can still inspect all Bayesian models that were fitted, explore their specifications, prior predictions or even use our posteriors as priors for your own research! Kind regards, Josef Mana