Prevalence and Treatment of Impulse Control Behaviours in Parkinson's Disease: A Meta- Analysis and Systematic Review

Objective Impulse control behaviours (ICBs) in Parkinson’s disease (PD) are common, but meta-analytical data on their prevalence and synthesised evidence for ICB treatments in PD are significantly outdated, necessitating an update that integrates newer studies. We systematically reviewed empirical studies to update the prevalence of ICBs in idiopathic PD and narratively synthesise the efficacy of existing therapeutic interventions. Methods We searched PubMed, Web of Science, EMBASE (Ovid), MEDLINE (Ovid), and the Cochrane Library from inception to June 1, 2023, including quantitative studies on human participants with idiopathic Parkinson’s disease. Risk of bias was evaluated using the Joanna Briggs Institute tool. The primary outcome measures were ICB prevalence and ICB changes following psychological, pharmaceutical, or brain-based interventions (Registry: Open Science Framework, 10.17605/OSF.IO/ASG2N). Results Thirty-seven studies were analysed. A random-effects meta-analysis of 27 studies (n = 17,906) found a mean event rate for at least one ICB in PD of 0.19 [95% CI = 0.15, 0.24], with evidence suggesting higher rates in patients taking dopamine agonists. A narrative synthesis of 10 studies (n = 283) found preliminary evidence for the effectiveness of cognitive behavioural therapy, levodopa infusion, atomoxetine, naltrexone, valproic acid, and deep brain stimulation in supporting ICB reduction. Conclusions ICBs represent a substantial comorbidity in PD. While several intervention strategies show promise, the paucity of high-quality treatment studies requires findings to be interpreted with caution. Clinical screening and large-scale tracking of ICBs in PD are recommended, alongside rigorous future trials.