Chronic sleep reduction in adolescents with Delayed Sleep Phase Disorder and effects of melatonin treatment

Homeostatic and circadian changes that occur during adolescence can result in chronic sleep reduction. This may particularly be true for adolescents with Delayed Sleep Phase Disorder (DSPD), which is associated with late Dim Light Melatonin Onset (DLMO). This study assessed the influence of melatonin treatment on chronic sleep reduction in adolescents with DSPD and examined whether adolescents with DSPD suffer from more chronic sleep reduction than adolescents from the general population before and after melatonin treatment. Adolescents with DSPD (n = 145; 55.9% boys; mean age 15,5 years; mean DLMO = 22:32 h) completed a questionnaire concerning chronic sleep reduction at baseline. From these, 53 adolescents also completed this questionnaire after on average 10 weeks of melatonin treatment. At baseline adolescents with DSPD reported significantly more symptoms of chronic sleep reduction than adolescents from the general population, whereas after treatment they reported significantly less symptoms. DLMO did not influence the effect of treatment. The improvement of chronic sleep reduction after treatment is an important finding, considering the negative consequences of chronic sleep reduction for adolescents' daytime functioning.