Sleep disturbances are associated with accelerated postural instability and death in Parkinson’s disease

<h3>Introduction</h3> Due to the progressive nature of Parkinson’s disease (PD), many individuals will develop complications such as falls, dementia, institutionalisation, and even death. Understanding the factors that contribute to these ‘milestones’ may lead to new therapeutic avenues. Sleep disturbances are amongst the commonest non-motor symptoms in PD. The aim of this study was to investigate the prevalence and prognostic significance of sleep disturbances in PD. <h3>Methods</h3> We utilised data from the ‘Parkinsonism: Incidence and Cognitive and Non-motor heterogeneity In CambridgeShire’ study. This is a prospective incident cohort that originally recruited 280 individuals with newly-diagnosed PD between 2008-2013 and undertook repeated clinical evaluations every 18 months. <h3>Results</h3> At baseline, 47% of participants reported poor self-reported sleep quality (PSQI&gt;5), while 15% reported excessive daytime sleepiness (ESS&gt;10). Poor quality sleep at baseline was found to predict faster progression to postural instability and death over a nine-year period. Excessive daytime sleepiness at baseline also predicted faster progression to postural instability, although this association did not retain statistical significance after accounting for covariates. <h3>Conclusion</h3> This study supports the hypothesis that sleep disturbances in PD are associated with adverse outcomes, potentially due to a shared underlying pathology or accelerated neurodegeneration resulting from sleep dysfunction.