Childhood narcolepsy with cataplexy: comparison between post-H1N1 vaccination and sporadic cases.
ABSTRACT We aimed to compare post-Pandemrix® vaccination (postvaccine) childhood narcolepsy with cataplexy (NC) vs sporadic pre-H1N1 pandemic (pre-H1N1) cases.
Clinical, anthropometric, polysomnographic, and cerebrospinal hypocretin 1 (hcrt-1) measurements were collected together with the video recordings of cataplexy in 27 Finnish patients with NC onset after H1N1 Pandemrix® vaccination (mean age, 12±4years; 52% boys) and 42 Italian NC patients with NC onset before the H1N1 pandemic (mean age, 11±3years; 48% boys). All subjects carried the HLA-DQB1*0602 allele.
Postvaccine subjects were older at NC onset (12±3 vs 9±3years; P=.008) and displayed a shorter mean sleep latency in multiple sleep latency tests (MSLT) (2.3±2.2 vs 3.7±2.9min; P=.026) compared to pre-H1N1 cases. Anthropometric, clinical (core NC symptoms), hcrt-1 deficiency, and polysomnographic data did not differ among groups, but higher disrupted nocturnal sleep was observed in postvaccine subjects. Comparison of cataplexy features at video assessment showed an overlapping picture with the exception for hyperkinetic movements which appeared to be more evident in pre-H1N1 subjects.
The clinical picture of childhood NC was similar in postvaccine and pre-H1N1 children.
- SourceAvailable from: Ilkka Julkunen[Show abstract] [Hide abstract]
ABSTRACT: Narcolepsy is a sleep disorder characterised by loss of hypothalamic hypocretin (orexin) neurons. The prevalence of narcolepsy is about 30 per 100 000 people, and typical age at onset is 12-16 years. Narcolepsy is strongly associated with the HLA-DQB1*06:02 genotype, and has been thought of as an immune-mediated disease. Other risk genes, such as T-cell-receptor α chain and purinergic receptor subtype 2Y11, are also implicated. Interest in narcolepsy has increased since the epidemiological observations that H1N1 infection and vaccination are potential triggering factors, and an increase in the incidence of narcolepsy after the pandemic AS03 adjuvanted H1N1 vaccination in 2010 from Sweden and Finland supports the immune-mediated pathogenesis. Epidemiological observations from studies in China also suggest a role for H1N1 virus infections as a trigger for narcolepsy. Although the pathological mechanisms are unknown, an H1N1 virus-derived antigen might be the trigger.The Lancet Neurology 06/2014; 13(6):600-613. · 21.82 Impact Factor