Mood disorders are said to affect about 20 percent of the population at one time or another in a month. About 12 percent report a form of major depressive mood disorder in a year and 17 percent in a lifetime. The increasingly popular bi-polar complaint that is made by substance abusers belies true bi-polar mood disorder, which is actually rare and is said to affect about 1 percent of the population. But there is much clouding of the numbers of true bi polar cases, because the manic episodes that are integral to a diagnosis of bi polar mood disorder are often not reported.
The mood disorders generally involve debilitating or major episodes. The episodes can involve specific types of elevations, depression or returns to normal mood. Major depression, hypomania, manic episodes, and the accompanying changes from one state to another are major features of the mood disorders.
In simplicity, there is excessive sadness, excessive joy, a return to a normal mood, or rapid switches between the extremes of mood. There are specific symptoms that must be present for a specific diagnosis of a particular mood disorder, and other causes such as physiological problems or other mental illness must be examined.
While most people go through changes in mood and even serious depressions at various times in life, it is the persistence, often for weeks and the severity that leads to more examination for a diagnosis. Grief over a major loss, bereavement and other life changing situations can resolve themselves over time, but it is the persistent and inconsolable case of mood disorder that requires more medical attention.
The mood disorders include: major depression, cyclothymia , SAD, and mania . Cyclothymia is a mild form of bipolar disorder. SAD is seasonal affective disorder.
Major depressive episodes can involve withdrawal from the world, irritability, anxiety, inability to handle loss or overly self critical behavior and impulsive behavior. There are feelings of hopelessness and possibly suicidal thoughts and tendencies. The condition can be completely debilitating and prevent completing essential life functions.
Manic episodes involve behavior and mood that is euphoric, hyperactive, with over inflated ego and unrealistic optimism as features. There may be risky behavior, flightiness: of ideas, ease of distractibility. There can be psychosis and severity enough to warrant hospitalization.
Mixed episodes involve rapid changes from Manic to depressed mood.
The Euthymic episode is a return to normal mood after a major depressive episode.
A hypomanic episode is a period of at least four days where the mood is "abnormally and persistently elevated, expansive or irritable". Unlike a Manic Episode, there is not enough severity to warrant hospitalization, there are no psychotic elements, and there is not enough impairment to require hospitalization.
Substance abuse, especially alcoholism and substance dependency are seen to be causes or related to mood and other psychiatric disorders, which complicates matters with separate, multiple and distinct diagnoses. In some cases, mood episodes can when the substance abuse is stopped. In other cases, such as nicotine addiction, a depressive mood episode can be triggered when the substance is stopped.
Depressive mood episodes can be aggravated by the consequences of specific symptoms. Chronic anxiety and need for protection or more attention can create spirals into extended depressive mood episodes when expectations of help are disappointed.
The DSM-IV-TR is the source of detailed information about mood disorders and provides a very readable amount of information.