Effects of light treatment upon mood and melatonin in patients with seasonal affective disorder

Ten patients with seasonal affective disorder received the following treatments for 5 days each: (a) artificial daylight (2500 lux) from 20.00 to 23.00 and from 07.00 to 10.00 hours; (b) red light (300 lux) from 20.00 to 23.00 and from 07.00 to 10.00 hours; (c) artificial daylight (2500 lux) from 22.00 to 23.00 and from 07.00 to 08.00 hours. The antidepressant effect of treatment (a) was superior to that of treatment (b), suggesting that the effect of light treatment in winter depression is more than that of a placebo. The antidepressant effect of treatment (a) was superior to that of treatment (c), although these two treatments equally suppressed plasma melatonin concentrations. Consequently, in these patients there is a dissociation between the effect of light treatment on melatonin and the reduction of depression ratings.

[1]  D A Newsome,et al.  Light suppresses melatonin secretion in humans. , 1980, Science.

[2]  A. Wirz-Justice,et al.  How much light is antidepressant? , 1986, Psychiatry Research.

[3]  T. Wehr,et al.  Treatment of Seasonal Affective Disorder with Light in the Evening , 1985, British Journal of Psychiatry.

[4]  M. Hamilton,et al.  Development of a rating scale for primary depressive illness. , 1967, The British journal of social and clinical psychology.

[5]  M. Friedman.  The Use of Ranks to Avoid the Assumption of Normality Implicit in the Analysis of Variance , 1937 .

[6]  J. Arendt.  Radioimmunoassayable melatonin: circulating patterns in man and sheep. , 1979, Progress in brain research.

[7]  A. Lewy,et al.  Antidepressant and circadian phase-shifting effects of light. , 1987, Science.

[8]  P. Cowen,et al.  Direct radioimmunoassay for melatonin in plasma. , 1983, Clinical chemistry.

[9]  F. Goodwin,et al.  Seasonal affective disorder. A description of the syndrome and preliminary findings with light therapy. , 1984, Archives of general psychiatry.

[10]  J. Arendt,et al.  Phototherapy of seasonal affective disorder. Time of day and suppression of melatonin are not critical for antidepressant effects. , 1986, Archives of general psychiatry.

[11]  T. Sensky,et al.  Phototherapy and its mechanisms of action in seasonal affective disorder. , 1988, Journal of affective disorders.

[12]  Lee J. Grota,et al.  Effects of bright incandescent light on seasonal and nonseasonal major depressive disorder , 1986, Psychiatry Research.

[13]  T. Wehr,et al.  Seasonal Affective Disorders , 1987 .