Low Intensity 'Blue Light' Treatment of Seasonal Affective Disorder

Study Overview
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Brief Summary
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One of the most frequently investigated hypothesis of the pathophysiology underlying Seasonal Affective Disorder(SAD) or so called winter depression is a disturbance of circadian rhythms. Since the circadian system is especially sensitive for the blue portion of the light spectrum, a new light therapy device with more blue light (blue enriched polychromatic light) was tested for its efficacy to treat SAD. In chronobiological terms this light is hypothesized to be more potent in inducing non-visual effects. In the present study fluorescent tubes that emit a high portion of short wavelength light on top of the normal wavelengths are tested for its superiority in treating SAD. This blue-enriched light (colour temperature 17000 ºK) is compared to standard light treatment (5000 º K) in SAD patients.,In a earlier study it was shown that the therapeutic effect of blue enriched light were equal to standard light treatment using light in both conditions with an intensity of 10 000 lux. In the present study, blue enriched light with an intensity of 750 lux was used, because of the possible saturation effect in the former study. The investigators hypothesise that blue- enriched light with a low intensity improve the therapeutic effects of light treatment leading to a higher response or the same response in a shorter time schedule compared to standard light treatment.

Official Title
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Randomized and Controlled Study of the Effects of Low Intensity 'Blue Light'in the Treatment of Seasonal Affective Disorder

Conditions
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Seasonal Affective Disorder

Intervention / Treatment
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* Device: Blue enriched light with a low intensity
* Device: standard light treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-65 Diagnose of Seasonal Affective Disorder, winter type according to DSM-IV SIGH SAD rating Higher then or equal to 18 on day 1 No other treatments for mood disorder during the study Stay in the Netherlands during the study Exclusion Criteria: Other axis-I disorders according to the DSM-IV Acute suicide risk Use of psychotropic drugs or photosensitizing drugs No other treatments for mood disorder during the study Diabetes or epilepsy Regular shift work

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard light treatment<br>standard light treatment 5000K; 10 000 lux | Device: standard light treatment<br>* standard light treatment, 30 minutes, 10 000 lux<br>* Other names: Philips Energylight HF 3309, 2 lamps PLL36 W, color 5000K, 10 000 lux;|
| Experimental: blue enriched light<br>Blue enriched light with a low intensity (750 lux) | Device: Blue enriched light with a low intensity<br>* 30 minutes in the morning, 750 lux<br>* Other names: Philips energy light HF 3309, 2 lamps PLL36 W 17000 K;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| SIGH-SAD | Structured Interview Guide of the Hamilton Depression Scale, seasonal affective disorder version | weekly | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Seasonal Affective Disorder, phototherapy, circadian rhythms, blue enriched light, melanopsin, low intensity