Microstructural White Matter Abnormalities in Children and Adolescents With Narcolepsy Type 1.

BACKGROUND: In 2010, the H1N1 Pandemrix vaccination campaign was followed by a sudden increase in narcolepsy type 1 (NT1). We investigated the brain white matter microstructure in children with onset of NT1 within two years after the Pandemrix vaccination. METHODS: We performed diffusion-weighted magnetic resonance imaging (MRI) on 19 children and adolescents with NT1 and 19 healthy controls. Imaging was performed at a median of 4 years after the diagnosis at a median age of 16 years. For the MRI, we used whole-brain tractography and tract-based spatial statistics (TBSS). We compared these results with medical records and questionnaire data. RESULTS: Narcoleptic children showed a global decrease in mean, axial, and radial diffusivity and an increase in planarity coefficient in the white matter TBSS skeleton and tractography. These differences were widespread, and there was an increased asymmetry of the mean diffusivity in children with NT1. The global microstructural metrics were reflected in behavior, and especially the axial diffusion levels correlated with anxiety and depression symptoms and social and behavioral problems. CONCLUSIONS: In pediatric patients with Pandemrix-associated NT1, several global changes in the brain white matter network skeleton were observed within five years after the onset of NT1. The degree of changes correlates with behavioral problems.

Finnish children who experienced narcolepsy after receiving the Pandemrix vaccine during the 2009-2010 H1N1 pandemic demonstrated high level of psychosocial problems.

AIM: We assessed psychosocial burdens in children who developed narcolepsy after receiving the Pandemrix H1N1 vaccine during the 2009-2010 pandemic. Parental quality of life was also assessed. METHODS: This multicentre study covered four of the five Finnish University Hospital Districts, which dealt with about 90% of the paediatric narcolepsy cases after the Pandemrix vaccination. The medical records of children diagnosed from 2010 to 2014 were reviewed. The questionnaires included the Youth Self-Report (YSR), Children's Depression Inventory (CDI), the Child Behaviour Checklist (CBCL) and questions on parental resources, stress and quality of life. RESULTS: We obtained the medical records of 94 children who were aged 5-17 years at the time of their narcolepsy diagnosis and questionnaire data for 73 of those children. Most children had strong narcolepsy symptoms, and 25% had CDI scores that suggested depression. In addition, 41% had total CBCL problem scores above the clinically significant limit and 48% were anxious, withdrawn and had somatic complaints. Sleep latency was weakly associated with the CBCL total problem score. Half of the children needed psychiatric interventions and parental stress was common. CONCLUSION: Depression and behavioural problems were common in children with narcolepsy after the Pandemrix vaccination and their parents frequently reported feeling stressed.