Ventricular orexin-A (hypocretin-1) levels correlate with rapid-eye-movement sleep without atonia in Parkinson's disease

patients with Parkinson’s disease (four males and four females) who underwent ventriculography during deep brain-stimulation surgery and performed full-night polysomnography before surgery. Results: Our results showed a positive correlation between orexin-A levels and REM sleep without muscle atonia. Conclusion: Our results suggest that high levels of orexin-A in Parkinson’s disease may be associated with loss of REM muscle atonia.