Objective: To assess the impact of symptom severity on health-related quality of life (HRQoL) in people with narcolepsy type 1 (NT1).
Methods: A total of 174 people with NT1 were enrolled. They completed the Narcolepsy Severity Scale (NSS) and EQ-5D-3L consisting of five dimensions (EQ-5D utility values) and a visual analog scale (EQ-5D VAS). The relationship between severity of symptoms and HRQoL dimensions was evaluated by Pearson correlation analyses. Logistic regression was used to identify significant predictors of HRQoL. Nomogram was established based on results of independent predictors of factors on logistic regression analyses.
Results: The mean score for NSS, EQ-5D utility values, and EQ-5D VAS were 29.8 (10.08), 0.78 (0.09), and 64.30 (19.84) in people with NT1, respectively. NSS score showed a significant correlation with self-care (r = 0.157, p < .05), usual activities (r = 0.236, p < .01), pain/discomfort (r = 0.174, p < .05), anxiety/depression (r = 0.2, p < .01), and EQ-5D utility values (r = -.261, p < .01). EDS (excessive daytime sleep), cataplexy, hallucinations, paralysis, and disrupted nocturnal sleep (DNS) were significantly associated to EQ-5D VAS (r ranged from -0.154 to -0.354, p < .05). EDS (OR = -0.297) and DNS (OR = -0.16) were predictors of HRQoL. NSS score (OR = -0.360) and treatment (OR = 0.215) were predictors of the metrics of HRQoL. The C-indices of the nomogram were 0.726.
Conclusion: The severity of symptoms could disrupt self-care and usual activities, and increase pain/discomfort and anxiety/depression. HRQoL might be improved by alleviating symptom severity.