[Effectiveness of bright light therapy in cyclothymic axis syndromes--a cross-over study in comparison with partial sleep deprivation].

In a preliminary crossover study, fifty patients with a cyclothymic axial syndrome were given bright-light treatment, while fifty other such patients were treated by means of partial sleep deprivation, 60% of the patients responded to bright-light treatment, as opposed to 50% of the patients partially deprived of sleep. The superior results of the bright-light treatment (Hamilton Depression Scale) are confirmed on the Nurses' Observation Scale for Inpatient Evaluation and the Profile of Mood States. Comparatively young patients with a not so extremely marked depression show the best response rates. Bright-light treatment is also effective against depressive disorders in non-seasonal depressions.