Pituitary volume and the effects of phototherapy in patients with seasonal winter depression: a controlled study.

Objectives: Our aims were to investigate the pituitary volume in patients with seasonal winter depression and healthy volunteers in winter and summer, and to assess the effects of phototherapy in these patients.

Method: The pituitary volume of 12 patients with winter depression and 12 healthy controls, paired according gender, age and menstrual cycle, were obtained from magnetic resonance imaging in winter and summer. Eight patients were submitted to phototherapy (10000 vs. 2500 lux) in a double-blind crossover fashion during the winter, and reassessed (symptoms and magnetic resonance imaging) after treatment.

Results: There were no significant differences in pituitary volume between controls and patients in winter or summer. Exposure to phototherapy (10000 lux) decreased the depressive symptoms (p = 0.004), but the glandular volume did not change (p = 0.5). However, the pituitary volume in winter showed a positive correlation with the severity of depression in these patients (r = 0.69, p = 0.04).

Conclusions: The results suggest that neither winter depression nor the change of seasons is associated with significant change in the pituitary volume. Despite the fact that this study was performed in a tropical area, phototherapy with 10000 lux showed to be an efficient treatment in this SAD patients sample.