When light exposure was administered at a symptomfree period at the beginning of autumn, however, it was not successful in preventing the development of winter depression.57 Partonen and Lonnqvist,58 in contrast, did find that bright light given well in advance of the emerging symptoms of winter SAD prevented a depressive episode. Effects on hypersomnia Hypersomnia has been associated with a superior response to morning light.59 In an open study design, Lam et al60 found that patients

with winter depression Inhibitors,research,lifescience,medical who had hypersomnia had greater improvement, particularly in atypical depression symptoms than patients with insomnia. Evening subjective sleepiness improves with morning light, even a short 15-min exposure, Inhibitors,research,lifescience,medical in patients with winter depression.61 Comparison with antidepressant medication Wirz-Justlce et al62 described a woman with SAD who, after remitting within a week in each of 6 separate trials of light therapy, remitted within 2 weeks of initiating citalopram, despite the delayed sleep and intermittent awakening induced with citalopram, but not with light therapy. Ruhrmann et al63 found that 70% of 40 SAD patients treated with bright light (3000 lux 2 h daily) were responders compared with 65% treated with fluoxetine (20 mg daily for 5 weeks). Light treatment Inhibitors,research,lifescience,medical improved

depression scores faster, while fluoxetine had a faster effect on atypical symptoms. In 13 SAD patients, Ghadirian et al64 compared light therapy for 2 weeks or tryptophan for 4 weeks in an open repeated-measures design. Tryptophan was equally effective to light therapy in treating SAD, but relapse after withdrawal of tryptophan occurred more slowly. Improvement of atypical depressive symptoms after 1 h of light

therapy Inhibitors,research,lifescience,medical positively correlated with improvement after 2 weeks of therapy.65 Comparison with natural light Eastman66 Inhibitors,research,lifescience,medical documented that the perceived sunlight exposure in SAD patients in Chicago was twice as much in summer than in winter: the perceived daylength was 4 to 5 h longer in summer than in winter, with a later perceived dusk contributing more to the lengthening than an earlier perceived dawn. Wirz- Justice et al67 observed that 50% of patients with SAD remitted after a daily 1-h morning walk outdoors in natural light, which phase-advanced the onset and/or offset of salivary melatonin secretion, and decreased morning Cortisol compared with low-dose artificial light, which did not modify depression self-ratings, or melatonin or Rolziracetam Cortisol patterns. The effects of bright light treatment (2500 lux) on subsyndromal SAD in the workplace have been studied,68 and both morning and afternoon exposure resulted in similar levels of improvement in mood, energy, alertness, and LY2835219 research buy productivity. Side effects Terman et al69 reviewed the ocular effects of particularly the more recent treatment approach of using approximately 10 000 lux light exposure for 30 min.