These symptoms must be present for at least two weeks, cause significant distress, and be severe enough to interfere with functioning. People who suffer from dysthymia are at increased risk for episodes of major depression. This produces a situation in which mild depression is present most of the time, with occasional periods of more severe depressive symptoms. It is natural to have some depressionfeel sad after a loss such as the death of a relative, or after a major disappointment at home or at work. Depression is more prevalent in women than men and is especially common among adolescents.
Mild depression comes and goes and is characterized by downheartedness, sadness, and dejection.
Sleep disruption and lack of sunlight during the winter months are other biological factors that can precipitate depressive symptoms. It appears that a tendency toward depression is often genetic, but that stressful life circumstances usually play a major role in bringing on depressive episodes. Problems with depression usually begin in adolescence, and are about twice as common in women as in men. Noticeably disturbed thought processes, poor communication and socialization, and sensory dysfunction indicate moderate depression. People with severe depression are withdrawn, without expression, indifferent toward their surroundings, and may show signs of delusional thinking and limited physical activity .