Progressive dopamine and hypocretin deficiencies in Parkinson’s disease: is there an impact on sleep and wakefulness?
Article first published online: 2 JUL 2012
© 2012 European Sleep Research Society
Journal of Sleep Research
Volume 21, Issue 6, pages 710–717, December 2012
How to Cite
WIENECKE, M., WERTH, E., PORYAZOVA, R., BAUMANN-VOGEL, H., BASSETTI, C. L., WELLER, M., WALDVOGEL, D., STORCH, A. and BAUMANN, C. R. (2012), Progressive dopamine and hypocretin deficiencies in Parkinson’s disease: is there an impact on sleep and wakefulness?. Journal of Sleep Research, 21: 710–717. doi: 10.1111/j.1365-2869.2012.01027.x
- Issue published online: 27 NOV 2012
- Article first published online: 2 JUL 2012
- Accepted in revised form 15 May 2012; received 25 Febrary 2012
- excessive daytime sleepiness;
- Parkinson’s disease
Sleep–wake disturbances are frequent in patients with Parkinson’s disease, but prospective controlled electrophysiological studies of sleep in those patients are surprisingly sparse, and the pathophysiology of sleep–wake disturbances in Parkinson’s disease remains largely elusive. In particular, the impact of impaired dopaminergic and hypocretin (orexin) signalling on sleep and wakefulness in Parkinson’s disease is still unknown. We performed a prospective, controlled electrophysiological study in patients with early and advanced Parkinson’s disease, e.g. in subjects with presumably different levels of dopamine and hypocretin cell loss. We compared sleep laboratory tests and cerebrospinal fluid levels with hypocretin-deficient patients with narcolepsy with cataplexy, and with matched controls. Nocturnal sleep efficiency was most decreased in advanced Parkinson patients, and still lower in early Parkinson patients than in narcolepsy subjects. Excessive daytime sleepiness was most severe in narcolepsy patients. In Parkinson patients, objective sleepiness correlated with decrease of cerebrospinal fluid hypocretin levels, and repeated hypocretin measurements in two Parkinson patients revealed a decrease of levels over years. This suggests that dopamine and hypocretin deficiency differentially affect sleep and wakefulness in Parkinson’s disease. Poorer sleep quality is linked to dopamine deficiency and other disease-related factors. Despite hypocretin cell loss in Parkinson’s disease being only partial, disturbed hypocretin signalling is likely to contribute to excessive daytime sleepiness in Parkinson patients.