The leading cause of disability worldwide is depression. It accounts for nearly 10% of all disabilities. A person’s emotion is the state of arousal defined by subjective states of feeling. A person’s affect is his or her pattern of observable behaviors. A person’s mood is a pervasive and sustained emotional response that can color perception. Depression can refer to a mood or to a clinical syndrome, a combination of emotional, cognitive, and behavioral symptoms. Clinical depressionis depressed mood accompanied by other symptoms such as loss of energy, loss of pleasure, fatigue, changes in sleep and appetite. Mania is the polar opposite of depression. It is a disturbance of mood accompanied by euphoria, grandiosity, decreased need for sleep, pressured speech.

Mood disorders are defined in terms of episodes – discrete periods of time in which the person’s behavior is dominated by either a depressed or manic mood. A person who experiences a single depressive episode might be diagnosed withunipolar mood disorder. Individuals with bipolar mood disorder experience episodes of both mania and depression. These depressive episodes are not just normal sadness that everyone experiences.

  1. The mood change is pervasive across situations and persistent over time. The person’s mood does not improve, even temporarily, when he or she engages in activities that are usually experienced as pleasant.
  2. The mood change may occur in the absence of any precipitating events, or it may be completely out of proportion to the person’s circumstances.
  3. The depressed mood is accompanied by impaired ability to function in usual social and occupational roles. Even simple activities become overwhelmingly difficult.
  4. The change in mood is accompanied by a cluster of additional signs and symptoms, including cognitive, somatic, and behavioral features.
  5. The nature or quality of the mood change may be different from that associated with normal sadness. It may feel “strange,” like being engulfed by a black cloud or sunk in a dark hole.

The first widely accepted classification system was proposed by Emil Kraepelin (1921). He divided the major forms of mental disorder into two categories: dementia praecox (schizophrenia) and manic-depressive psychosis. There were two issues though. Should disorders be defined in a broad or a narrow fashion? And the other issue was heterogeneity – all patients do not have exactly the same set of symptoms, the same pattern of onset, or the same course over time.

Unipolar Disorders

Unipolar disorders include two specific types: major depressive disorder and dysthymia. Dysthymia differs from depression in terms of severity and duration. A person diagnosed with dysthymia must have symptoms over a period of two years, exhibit depressed mood for most of the day on more days than not. The average age for the onset of unipolar disorders is 32. The length of episodes vary widely with the minimum duration being two weeks. Recovery periods are known as remission. A relapse is the return of active symptoms. Approximately half of unipolar patients recover in six months. Unipolar depression is one of the most common forms of psychopathology. 16% of NSC-R study (n = 9,000) suffered from depression.The lifetime risk of for bipolar I and II disorders combined is close to 4%. The ratio of unipolar to bipolar disorders is at least 5:1.

Bipolar Disorders

There are three types of bipolar disorders, all of which involves manic or hypomanic episodes (Bipolar I :At least onemanic episodeBipolar II: At least one hypomanic episode, no full blown manic episode; Cyclothymia: Bipolar equivalent of dysthymia). An individual diagnosed with cyclothymia ­must experience numerous hypomanic and depressive episodes during a two-year period. Bipolar disorders usually have an onset between ages of 18 and 22 years. The first onset can be depression or mania. The average duration of a manic episode runs between two and three months. Manic and depressive episodes can be intermittent. The long-term prognosis is mixed for individuals with bipolar disorder.

Generational Differences and Gender Differences

Mood disorders are more frequent among young and middle-aged adults. The frequency of depression has increased in recent years. People born after World War II seem more likely to develop mood disorders than earlier generations. Women are more likely than men to experience depression (or to admit they do). Women are more likely to seek mental health services than are men. Men and women are diagnosed about evenly with bipolar disorder.

Onset

Research on bipolar disorder is behind research on depression. Some evidence indicate that the weeks preceding the onset of a manic episode are marked by an increased frequency of stressful life events. Aaron Beck claims that pervasive and persistent negative thoughts are central in the onset of depression when they are activated by a negative event. This idea is referred to as the Cognitive Triad. Cognitive distortions are key to understanding depression as well. These distortions come in many forms: global personal meanings to experiences of failure, overgeneralization, arbitrary inferences, selective attention.

Genes play a bigger role in bipolar disorder than in unipolar disorder. There is an 80% chance that children of parents with bipolar mood disorder will have it themselves. This high percentage is due bipolar disorder being polygenic.

Treatments

Unipolar disorders are generally treated with antidepressant medications. There are four general categories for such medications: Selective Serotonin Reuptake Inhibitors (SSRIs), Tricyclics, Monoamine Oxidase Inhibitors (MOA-Is),  and the vague other. Improvement is generally seen four to six weeks after beginning medication. The current episode is often resolved within 12 weeks. The client continues medication usually for six to 12 months after entering remission.

SSRIs are the most frequently used antidepressant because they are easier to use than other antidepressants with fewer side effects (sexual dysfunction, weight gain) and are less dangerous in the event of an overdose.

Tricyclics (Imipramine and amitripyline) have more side effects (constipation, drowsiness, drop in blood pressure, blurred vision) but are just as effective as SSRIs.

MAO-Is (Phenelzine (Nardil)) are not as effective tricyclics. Like any medication, it has side effects. Consuming foods with tyramine (cheese and chocolate) while taking MAO-Is often increases blood pressure. MAO-Is can be used safely when foods such as cheese, beer, and red wine are avoided. This type of medication is most frequently used in treatment of anxiety disorders, particularly agoraphobia and panic.

For bipolar disorder,  lithium has proven to be an effective treatment in alleviation of manic symptoms; however, 40% of patients do not improve. Many patients stop taking the drug due to side effects.

Psychotherapy can be effective supplement to biological intervention, and the combination of psychotherapy and medication is more beneficial than medication alone.

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