Consistent depressive disorder, also known as dysthymia, is a problem that many people around the world suffer from. It is related to problems in the mood and will power. A serious depression can affect an adult at least two years, and adolescents and children for one year. Family members and friends of people suffering from chronic depression, often confuse the symptoms as part of the character and personality of the person. The most common symptoms of chronic depression are sudden changes in mood, or prolonged periods of sadness, crying, lack of will, reluctance, excessive sleep and other disorders.