To investigate the effects of bright light treatment on the symptoms of pain, mood, and sleep in patients with fibromyalgia (FM) reporting seasonality of symptoms on the Seasonal Pattern Assessment Questionnaire (SPAQ).
A randomized 10 week crossover study compared the effects of 4 weeks of "visible electromagnetic fields" (EMF) (light condition; mean 4750 lux, SD 2337 lux) to 4 weeks of "nonvisible EMF" (no light condition) in 14 patients with FM having a minimum SPAQ score of 11. The light visor system (Bio-Brite) was fitted with an opaque filter for the "nonvisible EMF" control condition.
No significant differences were found between treatment conditions on tenderness measured with dolorimetry, self-ratings of sleep, pain, mood, and global measures. Mood was not related to pain or sleep. There was significant reduction in depression scores and subjective pain, but increased tenderness and nocturnal awakenings related to time.
The were no significant differences between the light and no light conditions on pain, mood, or sleep in patients with FM reporting seasonality of symptoms. No relationship was found between mood and the symptoms of FM (i.e., pain, sleep, and fatigue).