Clinical and neurophysiological characteristics of 89 patients with narcolepsy and cataplexy from the Russian Narcolepsy Network.

STUDY OBJECTIVES First reports of narcolepsy with cataplexy (NC) in Russia were made by Mankovsky in 1925. The largest series of patients (n=110) was reported by A. Vein in 1964. However, until today narcolepsy remains relatively unknown in Russia. The aim of this study is to report clinical and polysomnography (PSG)/Multiple Sleep Latency Test (MSLT) results in the Russian population and compare them with the European Narcolepsy Network (EU-NN) data (n=1099) reported. METHODS Eleven sleep centers from Russia agreed to participate and completed a questionnaire including 58 questions concerning demographic, clinical, PSG and MSLT data. RESULTS There were 89 patients with a mean age of 35,6±16,9 years, 58% males and 42% females. Narcolepsy started at mean age of 25,6±14,6 years (range years). The mean Epworth Sleepiness Scale (ESS) was 18,4±3,5 points (range: 11-24). Sleep paralysis was reported by 59,1%, and hallucinations by 82% of patients. In MSLT 2 or more speed onsets of REM sleep periods (SOREMPs) were found in 81,6%. No center provided human leukocyte antigen (HLA) or cerebral spinal fluid (CSF) hypocretin data. CONCLUSIONS Clinical and neurophysiological data from this first study of the Russian Narcolepsy Network suggest a similar profile to the recently reported EU-NN data. The more severe and higher percentage of patients with cataplexy and presenting with both excessive daytime sleepiness (EDS) and cataplexy may reflect low awareness of narcolepsy in Russia. CLINICAL TRIAL REGISTRATION Registry: Clinical Trials (service of NIH); Title: Clinical and Neurophysiological Characteristics of Narcolepsy; Identifier: NCT05375890; URL: https://clinicaltrials.gov/ct2/show/NCT05375890