Impaired attention in pediatric narcolepsy type 1.

PURPOSE: Attentional complaints are common among youth with Narcolepsy Type 1 (NT1), yet objective data are limited. We hypothesized that adolescents with NT1 would show worse attention on a 3-min Psychomotor Vigilance Task (PVT) than healthy controls (HC), with performance correlating to self-reported sleepiness and increased sleep stage transition.

METHODS

Twenty-six NT1 participants (mean 15.9 years) and 16 HC (mean 16.3 years) completed 3-min PVT testing in the evening and morning pre/post nocturnal polysomnography (PSG). Sleep to Wake/N1 transitions and N1% were extracted from PSG data as measures of disrupted nighttime sleep and Epworth Sleepiness Scale (ESS) scores were collected. PVT outcomes included lapses, mean 1/RT, and slowest 10% 1/RT. Linear mixed models examined group differences and effects of age, gender, test timing, and group-time interactions.

RESULTS

NT1 participants had more lapses (p < .001), slower mean 1/RT (p = .003), and slower slowest 10% 1/RT (p = .021). Across all participants, poorer PVT performance moderately correlated with higher ESS scores (partial correlation r = .48) and increased Wake/N1 (r = .35) and N1% (r = .49, all p's < .005). Results remained significant after adjusting for cofounders. No within group associations were observed.

CONCLUSION

Adolescent NT1 patients exhibit impaired attention vs. HC as measured by 3-min PVT. While daytime sleepiness and poor sleep quality contribute, modest correlations suggest additional factors. Given that orexin receptors reside in attention-related cortical areas, deficient orexin signaling may play a more direct role in these deficits and warrants further investigation.

STUDY RATIONALE: Adolescents with Narcolepsy Type 1 (NT1) frequently report problems with attention, yet objective data on attention in this population are limited. This study aimed to assess objective measures of attention in pediatric NT1 using psychomotor vigilance testing and understand their relationship with sleep quality and subjective sleepiness.

STUDY IMPACT: Our findings reveal significant objective attention deficits in NT1 youth compared to healthy controls suggesting psychomotor vigilance testing could be a useful tool to objectively measure attention concerns in clinic and research settings.