Esophageal motor impairment in REM-sleep behavior disorder: A biomarker of early Parkinson's disease?

Rapid-eye-movement (REM) sleep behavior disorder (RBD) is a parasomnia defined by intermittent loss of skeletal muscle atonia during REM sleep with emergence of complex and vigorous behaviors by acting out dreams. Patients with idiopathic RBD have an 80–90% risk to convert to an alpha synucleinopathy (especially PD, in rare cases MSA or Dementia with Lewy bodies) within 10 years. Therefore, RBD might serve as a preclinical marker with a high...