Trauma Immediately Preceding REM-Behavior Disorder: A Valuable Prognostic Marker?

Area of Science:

• Neurology
• Sleep Medicine
• Psychiatry

Background:

• Rapid eye movement sleep behavior disorder (RBD) definitions have evolved, encompassing idiopathic, trauma-associated, and overlap parasomnia forms.
• The prognostic significance of trauma in RBD remains unclear.
• Distinguishing trauma-associated RBD from idiopathic RBD (iRBD) is crucial for understanding neurodegenerative risk.

Purpose of the Study:

• To investigate if RBD secondary to trauma has a lower likelihood of progressing to neurodegeneration compared to iRBD without a trauma history.
• To determine the prognostic specificity of trauma in the context of RBD development.

Main Methods:

• A retrospective cohort study included 122 RBD patients diagnosed via video polysomnography (vPSG).
• Patients were interviewed for trauma history, categorized by trauma timing relative to RBD onset (within 12 months, >12 months prior, or no trauma).
• Exclusion criteria applied to patients with secondary RBD from known causes; follow-up extended up to 18 years.

Main Results:

• No patients (n=35) experiencing trauma within 12 months before RBD onset developed neurodegenerative disorders.
• In contrast, 38% of patients without recent trauma developed neurodegenerative illnesses.
• Patients with neurodegeneration were more likely to have a family history of alpha-synucleinopathy or tauopathy.

Conclusions:

• RBD developing within 12 months of a traumatic event, clinically resembling iRBD, did not show phenoconversion to neurodegeneration over 18 years.
• A distinct subtype of RBD secondary to trauma is proposed.
• Comprehensive psychological and trauma assessments are recommended for all patients with dream enactment behaviors (DEB).