Major depression, seasonal pattern (seasonal affective disorder SAD) characterize the winter recurrence depressive episodes with remission of symptoms in spring and summer. Patients with winter depression report hypersomnia, fatigue, loss of energy, carbohydrate craving, appetite and weight gain.
Aim: The aim of this study was to assess the effect of phototherapy on the quality of sleep parameters and subjective estimation of mood disorders in patients with seasonal affective disorders.
Method: The investigated group consisted of 17 patients with SAD (15 female, 2 male) aged 18-64 (mean 38+/-12) years. Phototherapy (bright light therapy) was applied for 14 days, everyday morning--30 minutes, between 6.00 to 10.00--exposition to light of about 10,000 lux intensity. Polysomnogram (sleep EEG) was recorded before and after treatment.
Results: After phototherapy patients reported a significant mood improvement (57%) measured by the Seasonal Pattern Assessment Questionnaire. Sleep investigation showed: increased sleep efficiency, decreased sleep latency, decreased slow wave sleep latency and increased of sleep spindles in the first hour of sleep.
Conclusions: Research confirms that phototherapy is an effective method of treatment of choice for patients with SAD. The result indicates that phototherapy markedly improved mood and sleep quality.