The phototherapy light visor: More to it than meets the eye

Department of Psychiatry, Harvard Medical School, Boston, USA.
American Journal of Psychiatry (Impact Factor: 12.3). 09/1995; 152(8):1197-202.
Source: PubMed


The purpose of the study was to ascertain whether phototherapy light visors provide an effective treatment for seasonal affective disorder. Previous studies have demonstrated a moderate response rate but have failed to find any difference in efficacy between light intensities.
Subjects were randomly assigned to receive, over a 2-week treatment period, 30 minutes of morning phototherapy with a light visor that emitted either a dim (30-lux) red light or a bright (600-lux) white light. Raters were blind to treatment, and patients were unaware of the alternatives. Response was assessed by using the structured 21-item Hamilton Depression Rating Scale, with an eight-item addendum for atypical depressive symptoms. Fifty-seven patients were enrolled across two sites.
Patients assigned to the different visors had similar baseline depression scores and similar expectations of outcome. Hamilton depression scale scores declined by 34.6% for subjects given bright white light and by 40.9% for subjects given dim red light. Scores for atypical depressive symptoms fell by 44.1% for patients assigned the bright white light visors and by 49.0% for patients assigned the dim red light visors. Altogether, 39.3% of the patients who received red light and 41.4% of the patients who received bright white light showed a full clinical response.
There were no significant differences in therapeutic response between patients who were treated with red or white light. The results of this study suggest that the phototherapy light visor may function as an elaborate placebo. Alternative explanations, however, are considered.

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    • "Various studies have tried to distill the appropriate spectrum of light for BLT [14, 15, 21]. While some studies yield conflicting results, full spectrum white light (with filtered UV) has consistently been used for BLT. "
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    ABSTRACT: We present “Lightwear”, a series of garment-based, lightweight, light-emitting wearables designed to administer light therapy for on-the-go treatment of Seasonal Affective Disorder (SAD). Bright Light Therapy (BLT) has been used to treat SAD for more than 25 years. While light boxes continue to serve as the predominant method of treatment, it often requires a user to sit at a dedicated location for a sustained period of time (30-60 minutes), rendering therapy inconvenient and resulting in unsatisfactory compliance rates. To date, there have been few successful products developed for wearability and portability to ease the uncomfortable nature of light box treatment. However, new low-profile, light-emitting sources yield opportunities for less cumbersome textile integration and wearability. We explore the integration of light into textile substrates that focus on fashion-forward wearables which can,
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    • "The evaluations of initial expectancy scores in the visor studies indicated that the patients had the same expectations for therapeutic effects of proposed active and placebo treatments (i.e. Teicher et al. 1995). Consequently, these results of the studies with headmounted devices showed that clinical outcome is not related to intensity, color or duration of light. "
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    • "To our knowledge, only six studies have examined the antidepressant response to bright light therapy with a credible placebo control treatment that produced similar expectations for improvement as the bright light treatment. Three of these studies used head-mounted light visors and compared bright white light to dimmer light (Joffe et al., 1993; Rosenthal et al., 1993; Teicher et al., 1995). Another study used head-mounted light visors but compared bright red light to dimmer red light (Levitt et al., 1994). "
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