The RT-QuIC Assay as a Marker for Later Synucleinopathy in REM Sleep Behavior Disorder

The assay was highly sensitive and specific and identified patients with RBD at increased risk for Parkinson disease or dementia with Lewy bodies.

Rapid eye movement (REM) sleep behavior disorder (RBD) is considered a prodromal stage of both Parkinson disease and dementia with Lewy bodies. Real-time quaking-induced conversion (RT-QuIC) analysis of cerebrospinal fluid (CSF) can detect misfolded α-synuclein, the primary constituent of Lewy bodies. To test whether RT-QuIC could detect CSF α-synuclein in patients with isolated RBD, investigators performed lumbar puncture for CSF RT-QuIC α-synuclein analysis in 52 patients with video polysomnography–confirmed isolated RBD and 40 controls.

The RT-QuIC assay was positive in 47 patients (90%) with RBD and four healthy controls (10%). The sensitivity was 90.4% and specificity was 90.0%. At a mean of 3.4 years later, 32 (62%) were diagnosed with…

Reviewing Author

Michael S. Okun, MD

Disclosures

Consultant/Advisory BoardParkinson’s Foundation; Tourette Association of America

Speaker’s BureauMedscape/WebMD CME, Movement Disorders Society CME, American Academy of Neurology CME

RoyaltiesBooks4Patients; Demos; Cambridge; Taylor and Francis; Robert Rose; Public Affairs

Grant/Research SupportNational Institutes of Health; Parkinson’s Foundation; Tourette Association of America; University of Florida Foundation

Editorial BoardsTremor and Other Hyperkinetic Movements; JAMA Neurology

Leadership Positions in Professional SocietiesParkinson’s Foundation (Medical Advisor)