Light therapy for the treatment of delayed sleep-wake phase disorder in adults: a systematic review.

Delayed sleep-wake phase disorder (DSWPD) is characterized by sleep onset times, beyond the usual schedules and social conveniences, which potentially impacts on health as well as on school and professional performance. The most common treatment for DSWPD is the light administration (light therapy), through light devices, with or without behavioral instructions. Since there is no consensus in the literature about its efficacy and how it should be processed, this study aims to evaluate the light therapy effectiveness in the delayed sleep-wake phase disorder therapeutics.