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

摘要

Delayed sleep-wake phase disorder (DSWPD) is characterized by sleep onset times,beyond the usual schedules and social conveniences, which potentially impacts onhealth as well as on school and professional performance. The most commontreatment for DSWPD is the light administration (light therapy), through lightdevices, with or without behavioral instructions. Since there is no consensus inthe literature about its efficacy and how it should be processed, this studyaims to evaluate the light therapy effectiveness in the delayed sleep-wake phasedisorder therapeutics. A systematic review was conducted using theMEDLINE/PubMed, Virtual Health Library Brazil, PsycINFO, Web of Science andScopus databases along with a hand search until September 2020. The includedstudies presented participants diagnosed with insomnia or DSWPD, over 18-yearsold, treated only with morning light therapy, mentioning the light intensity(lux) used, and investigations with a control group. Studies reportingindividuals with neurological or psychiatric disorders, shift-workers, orevaluating other sleep disorders were excluded. Among the 411 studiesidentified, five were selected for this review, resulting in a total sample of140 individuals. Only two studies produced long-term results, showing that thebenefits did not persist. In most studies, there were no statisticallysignificant differences in the variables when comparing the intervention groupand the control group. However, there were substantial clinical and laboratoryadvances in the sleep phase using light therapy when comparing phase advancesfor the same group concerning baseline values of sleep variables.