Narcolepsy is associated with an increased risk of HLA-related autoimmune diseases: Evidence from a Nationwide Healthcare System Database in South Korea

Abstract

<b>Study Objectives:</b> To determine the incidence of narcolepsy in South Korea and to closely examine the relationship between narcolepsy, which is believed to be an autoimmune response, and other systemic autoimmune diseases. <b>Methods:</b> We examined data from the South Korean nationwide health insurance claims database from 2010 to 2019. Our study included patients with narcolepsy, and age- and sex-matched controls without narcolepsy. We estimated the incidence of narcolepsy and the odds ratio of narcolepsy and associated autoimmune comorbidities in South Korea. <b>Results:</b> We identified 8,710 patients with narcolepsy (59.8% men and 40.2% women). The incidence of narcolepsy was 0.05%. Patients with narcolepsy are at a significantly high risk of ankylosing spondylitis, rheumatoid arthritis, and Sjögren’s syndrome, which are related to human leukocyte antigen (HLA) genes. <b>Conclusions:</b> Narcolepsy is closely associated with systemic autoimmune diseases, particularly those related to HLA genes.