Question

Carefully distinguish between bipolar disorder, unipolar disorder, dysthymic disorder, and cyclothymic disorder.

Answer 1

All four are different types of Depressive Disorders. The major difference or distinction between them are in terms of severity, symptoms or their duration.

Bipolar Disorder is characterized by cycling between elated moods and depressed moods. It forms a wave like structure. Patient is diagnosed as having bipolar disorder if and only if he/she has had episodes of mania or hypomania intermingled with episodes of depression.

Unipolar Disorder is characterized by low moods or depression. Its symptoms are as per the diagnosis given in DSM (Diagnostic and Statistical Manual) for Major Depressive Disorder (MDD). It is called unipolar disorder due to the mood of the patient remaining at one pole (low mood), as compared to that of bipolar disorder which has two poles (elated and low moods).

Dysthymic disorder is similar to unipolar Disorder. It is less severe, but a chronic form of depression. In this disorder the low mood exists for two years or longer. While, in the case of Major Depressive disorder, there are phases of low mood (extreme depression for two weeks or more with single or recurrent episodes).

Cyclothymic Disorder is a less severe form of Bipolar disorder. The low and high moods do not reach the severity or the duration of that of Major Depressive Disorder or of full Mania episodes. The episodes are characterized as mostly being hypomanic episodes, rather than manic episodes and the duration is less (less than 2 weeks, unlike that of MDD or Bipolar). Severity is mild for both episodes, owing for this disorder to be left undiagnosed or untreated in most of the cases.