In this case, depression usually occurs in the fall or winter and gets better in the spring. It must be a pattern for at least two years before a diagnosis is made. In a depressive episode without a seasonal pattern, symptoms such as lack of sleep and weight loss are common. Depressive episodes that occur in a seasonal pattern differ from typical depressive episodes. It is hard to know how many people with depression have a seasonal pattern.
Younger people are more likely to be affected than older people.
Women may be more likely to have a seasonal pattern than men. The further north you live, the more likely you are to be affected. Treatment for depressive episodes with a seasonal pattern is the same as for other forms of depression. An antidepressant drug may be used. Bright light therapy may be helpful.