Résumé
OBJECTIVES: Narcolepsy is characterized by excessive sleepiness, cataplexy, sleep paralysis and hypnagogic hallucination. As there have been few researches on narcolepsy symptomatology in adolescents, we examined gender differences and prevalence of narcolepsy tetrad among students attending high school. METHODS: Total 20, 407 subjects, ages 14-19 years filled out Ullanlinna Narcolepsy Scale (UNS). Subjects whose UNS scores were equal to or more than 14 were interviewed by telephone using semi-structured questionnaire. Variables included questions to evaluate tetrad of narcolepsy. RESULTS: UNS scores were higher in female than male (11.1+/-5.2 vs. 9.6+/-4.5, p or = 14 were significantly higher in female subjects than male ones. However, no significant gender difference was observed in the frequencies of severe sleep attack and cataplexy-like symptoms. Sleep paralysis was most frequently reported during sleep. There was significant correlation between sleep paralysis and hypnagogic hallucination (r=0.235, p< 0.01). CONCLUSIONS: Our findings were that female adolescents complained more frequently narcolepsy symptoms than male subjects. Female adolescents might be more sensitive than male ones to physical complaints such as sleepiness or muscle weakness.