monochromatic blue light vs standard light treatment in seasonal complaints

Background of the study:

Seasonal affective disorder, wintertype, according to DSM-IV is depreesion with a seasonal pattern in wich the complaints exist in fall/winter and remission tooks place in spring/summer at an almost yearly basis.Epidemiological research in the Netherlands shows that 3% of the adults suffer from SAD and 8% from winterblues..



It has been shown that light treatment is effective, but the etiology of SAD and the working mechanism of light treatment are still unknown. One of the hypotheses is the phase shift hypothesis, which postulated that some biological processes are shifted compared to the 24 h rhythm of the environment. Exposure to bright light can cause a phase shift. If the biological clock is running in phase, SAD complaint can improve..



Recently novel photoreceptors in the eye are discovered. They have no influence on the visual system, but are sensitive for light, especially for light with a short wavelength (blue light). If blue light with a low intensity can have the same effect s compared to standard light therapu with a high intensity, than it is possible to ssimplify the traetment an to incorperate it in the life style of the

Objective of the study:

To investigate the effects of exposure to low intensity monochromatic blue light compared to the effects of standard light trherapy in the treatment of SAD and winterblues

Study design:

A treatment stud in which in the experimental condition teh effects of exposure of low inetnsity blue monochromatic light is compared to the effects of exposure tot standard light treatment in the treatment of SAD and winterblues

Study population:

Patiens suffering from SAD are recruted from the SAD outpatient clinic of the UMCG. Participant suffering from winterblues are recruted by means of advertisements in local newspapers

Intervention (if applicable):

Experimental treatment is exposure to low intensity blue monochromatic light, compared to standard light treatment

Primary study parameters/outcome of the study:

Sores on the SIGH-SAD interviews

Seasonal affective disorder, wintertype, according to DSM-IV is depreesion with a seasonal pattern in wich the complaints exist in fall/winter and remission tooks place in spring/summer at an almost yearly basis.Epidemiological research in the Netherlands shows that 3% of the adults suffer from SAD and 8% from winterblues..



It has been shown that light treatment is effective, but the etiology of SAD and the working mechanism of light treatment are still unknown. One of the hypotheses is the phase shift hypothesis, which postulated that some biological processes are shifted compared to the 24 h rhythm of the environment. Exposure to bright light can cause a phase shift. If the biological clock is running in phase, SAD complaint can improve..



Recently novel photoreceptors in the eye are discovered. They have no influence on the visual system, but are sensitive for light, especially for light with a short wavelength (blue light). If blue light with a low intensity can have the same effect s compared to standard light therapu with a high intensity, than it is possible to ssimplify the traetment an to incorperate it in the life style of the

In a 15 days study design, assessments by means of a standardized structured interviews (SIG-SAD) at iselection/inclusion and at day 1, 8 and 15 (primary outcome)

Daily self ratings (KSS; GSQS; AMS; AD-ACL)

Self ratings at inclusion (expectation, SPAQ and MEQ) and at day 15 (evaluation)

1. Patients with Seasonal Affective Disorder, age 18yr. or older

A comparison of the effects of exposure to monochromatic light (blue light) vs standard light treatment
5 consecutive days from 8.00-8.30 a.m. in the clinic, at day 4, 5, 6, 7, 8 of the 15 days study design

2. Subjects with sub-syndromal Seasonal Affective Disorder (winter blues), age 18 yr. or older

A comparison of the effects of exposure to monochromatic light (blue light) vs standard light treatment
5 consecutive days from 8.00-8.20 a.m. or earlier after awakening at home, at day 4, 5, 6, 7, 8 off the 15 days study design