Adjunctive Bright Light Therapy in Adolescents With Depression and Eveningness

Bright Light Therapy for Adolescents With Depression and Eveningness - a Randomized, Placebo-controlled, Assessor-blinded Study

This study examines the efficacy of bright light therapy as a treatment for adolescents diagnosed with unipolar non-seasonal depression who exhibit an evening chronotype.

This randomized, placebo-controlled, assessor-blinded trial aims to evaluate the efficacy of bright light therapy (BLT) as a treatment for adolescents with depression and evening chronotype. Eligible participants will be randomized to receive either BLT or dim red light (placebo) daily for 8 weeks. Depression severity, sleep parameters, and circadian markers will be assessed at baseline, during treatment, post-treatment, and at follow-up visits.

Inclusion Criteria:

1. Chinese, aged 12-19 years old;
2. Written informed assent/consent of participation into the study is given by the participant and his/her parent or guardian (for those aged under 18), respectively;
3. Having a DSM-5 diagnosis of unipolar non-seasonal depression as confirmed by the Chinese version of the Kiddie-Schedule for Affective Disorders and Schizophrenia (K-SADS) psychiatric interview, DSM-5 Seasonal specifier, AND having a score on Children's Depression Rating Scale (CDRS-R) at least 40;
4. Being classified as evening chronotype according to the score on the reduced Horne-Östberg Morning-Eveningness Questionnaire (rMEQ), i.e. <12.

Exclusion Criteria:

1. A current diagnosis of substance abuse or dependence; a current or past history of manic or hypomanic episode, schizophrenia spectrum disorders, organic mental disorders, or intellectual disabilities;
2. Having a clinically significant suicidality (presence of suicidal ideation with a plan or an attempt) as assessed by K-SADS;
3. Having been enrolled in any other clinical trial investigational products within one month at the entry of the study;
4. Initiation of or change in antidepressant medication within past 4 weeks;
5. Having been or is currently receiving any structured psychotherapy;
6. With hearing or speech deficit;
7. Night shift worker;
8. Trans-meridian flight across at least two time zones in the past 3 months and during the study;
9. Presence of an eye disease, e.g., retinal blindness, severe cataract, glaucoma.