发作性睡病不是罕见疾病;在西欧和美国的流行率估计为每 1000 人 0.2 至 2 例。[6]Aldrich MS. The clinical spectrum of narcolepsy and idiopathic hypersomnia. Neurology. 1996 Feb;46(2):393-401.http://www.ncbi.nlm.nih.gov/pubmed/8614501?tool=bestpractice.com[7]Hublin C, Partinen M, Kaprio J, et al. Epidemiology of narcolepsy. Sleep. 1994 Dec;17(8 Suppl):S7-12.http://www.ncbi.nlm.nih.gov/pubmed/7701204?tool=bestpractice.com[8]Silber MH, Krahn LE, Olson EJ, et al. The epidemiology of narcolepsy in Olmsted County, Minnesota: a population-based study. Sleep. 2002 Mar 15;25(2):197-202.http://www.ncbi.nlm.nih.gov/pubmed/11902429?tool=bestpractice.com它是白天嗜睡第二大常见病因,仅次于阻塞性睡眠呼吸暂停。[9]Zeman A, Britton T, Douglas N, et al. Narcolepsy and excessive daytime sleepiness. BMJ. 2004 Sep 25;329(7468):724-8.http://www.ncbi.nlm.nih.gov/pubmed/15388615?tool=bestpractice.com在美国大约有 12.5 万人患有发作性睡病。[2]Berry BR, Gilmore RL. Narcolepsy and idiopathic hypersomnia. In: Carney PR, Berry RB, Geyer JD, eds. Clinical sleep disorders. Philadelphia, PA: Lippincot Williams and Wilkins; 2005.男女皆可患有发作性睡病,男性比例略高。[8]Silber MH, Krahn LE, Olson EJ, et al. The epidemiology of narcolepsy in Olmsted County, Minnesota: a population-based study. Sleep. 2002 Mar 15;25(2):197-202.http://www.ncbi.nlm.nih.gov/pubmed/11902429?tool=bestpractice.com[10]Ohayon MM, Priest RG, Zulley J, et al. Prevalence of narcolepsy symptomatology and diagnosis in the European general population. Neurology. 2002 Jun 25;58(12):1826-33.http://www.ncbi.nlm.nih.gov/pubmed/12084885?tool=bestpractice.com
任何年龄段均可诊断发现,但是更常见于学龄期或青春期,极罕见于 5 岁以下和 75 岁以上的老年人。[11]Okun ML, Lin L, Pelin Z, et al. Clinical aspects of narcolepsy-cataplexy across ethnic groups. Sleep. 2002 Feb 1;25(1):27-35.http://www.ncbi.nlm.nih.gov/pubmed/11833858?tool=bestpractice.com
虽然自 90 年代以来,对该疾病的意识和认知不断增长,但是仍难以确定发病频率的趋势。