Women constitute a majority of the patients and often complain of aggravation of premenstrual mood changes during the fall and winter. The onset of the disorder is usually in the 20s, although it may occur at all ages. It is not unusual for these patients to self-medicate their depression with alcohol, caffeine, or cigarettes. The usual characteristics of recurrent winter depression are sometimes augmented by other features such as decreased sexual functioning, lethargy, hopelessness, suicidal thoughts, and social withdrawal. The symptoms of winter SAD usually begin in October or November and subside in March or April.
Depressions are usually mild to moderate, but they can be severe.
Only six percent of patients have required hospitali-zation and only one percent have ever been treated with electroconvulsive therapy. Patients who live farther north appear to have a longer and more profound winter depression than those living farther south. Oftentimes SAD patients will also report that their depression worsens whenever the weather is overcast or the indoor lighting is decreased. SAD, as other depression, is oftentimes misdiagnosed as hypothyroidism, hypoglycemia, infectual mononucleosis or fibromyalgia. Recurrent summer depression may also occur but usually includes insomnia and anxiety versus the hypersomnia and slowed-down state in the winter.