Skin biopsy confirms absence of alpha-synuclein in patients with trauma associated sleep disorder: A case series.

Trauma-associated sleep disorder (TSD) is a parasomnia characterized by trauma-related nightmares and dream enacting behavior, a feature that makes it difficult to distinguish from isolated REM sleep behavior disorder (iRBD). While iRBD has been associated with neurodegenerative disorders of alpha-synuclein deposition, the association between TSD and neurodegeneration is unknown. Skin biopsy and autonomic testing have emerged as promising biomarkers of synuclein-driven neurodegeneration in in iRBD. We employed these techniques in three patients with TSD and found normal autonomic function and no evidence of cutaneous synuclein, arguing against synuclein-driven neurodegeneration in TSD.