Main author: Birna Baldursdóttir
Institution or Company: Department of Psychology, Reykjavik University
Co-Authors, Institution or Company:
Hannah Rós Sigurðardóttir Tobin, Department of Psychology, Reykjavik University. Jakob Fannar Stefánsson, Department of Psychology, Reykjavik University. Snæfríður Guðmundsdóttir Aspelund, Department of Psychology, Reykjavik University. Huldís Franksdóttir Daly, Department of Psychology, Reykjavik University. Erlingur Jóhannsson, School of Education, University of Iceland. Heiðdís B. Valdimarsdóttir, Department of Psychology, Reykjavik University.
Introduction: Sleep deficiency is a major public health issue among young adults, affecting daily life and health. Sleep problems are usually due to a disruption in the body´s circadian rhythms (CR). Bright light therapy (BLT) is effective in realigning the CR in patients but the effectiveness of BLT among healthy young adults has not been evaluated. Thus, the present study examined the effects of BLT on sleep problems and sleep quality in a sample of healthy young adults with non-clinical sleep problems.
Methods: A 3-weeks BLT intervention, using circadian stimulating glasses for 30 minutes each morning, was conducted among 40 undergraduate students at Reykjavik University. Participants were randomly assigned to a control group with non-circadian stimulating dim white light (DWL) glasses or to an intervention group with circadian stimulating bright white light (BWL) glasses. At baseline and follow-ups, sleep problems were measured with the Bergen Insomnia Scale and sleep quality was measured with the Pittsburgh Sleep Quality Index. A 2-x-3 factorial design was applied to test the effectiveness of the BLT.
Results: Sleep improved in the BWL group but not in the DWL group as indicated by the significant interaction between group and time in both sleep problems (p = 0.005) and sleep quality (p = 0.045).
Conclusion: The results indicate that the circadian stimulating light glasses were effective in decreasing sleep problems and increasing subjective sleep quality. This has important public health relevance as this low-burden BLT intervention can easily be disseminated among young adults with non-clinical sleep problems.