Depression: Symptoms and Diagnosis

An Official Definition

The World Health Organization gives comprehensive criteria for the diagnosis of depressive disorders. The International Classification of Diseases ICD-10 gives these criteria for a mood disorder diagnosis:

"…the fundamental disturbance is a change in affect or mood to depression (with or without associated anxiety) or to elation. The mood change is usually accompanied by a change in the overall level of activity; most of the other symptoms are either secondary to, or easily understood in the context of, the change in mood and activity. Most of these disorders tend to be recurrent and the onset of individual episodes can often be related to stressful events or situations."

Bipolar Affective Disorder

This disorder is characterized by a disturbance in moods, divided into energetic, manic periods and apathetic, depressed periods. The professional making the diagnosis will first confirm that a sufferer has had repeated fluctuations of mood, i.e., that it has happened more than twice. Some practitioners will make a distinction between Type I Bipolar for serious fluctuations, and Type II Bipolar for less dramatic swings.

Depressive Episode

This is a single episode of depression. Moods, energy and activity levels are all lowered. Concentration levels are often reduced, and capacity for enjoyment is almost always lowered. Sleep may be disturbed, and many sufferers report that they tire easily. Appetites for food, pleasure and sex usually diminish, although some sufferers may increase eating, but without enjoyment. Anxiety and agitation are common.

A diagnosis will usually include a classification of severity, for example mild, moderate or severe. This classification is based on the amount and severity of individual symptoms.

Recurrent Depressive Disorder

When a sufferer has repeated depressive episodes, they may be diagnosed with recurrent depressive disorder. Manic episodes in between the lows may indicate bipolar disorder instead. Recurrent depressive disorder has no such highs, but will instead include a leveling out between depressive episodes.

Cyclothymia

Numerous periods of mild depression and mild elation indicate a diagnosis of cyclothymia. It is most likely to be found in the relatives of those with bipolar affective disorder, with which it shares many similarities. Sufferers with cyclothymia may also develop bipolar affective disorder themselves.

Dysthymia

A cousin of recurrent depressive disorder, dysthymia tends to have shorter depressive episodes, or episodes of less severity. However, sufferers are likely to feel at least somewhat depressed a majority of the time. They often struggle with neuroses and persistent anxiety.