Depressive Disorders Health Article

Definition

A depressive disorder is defined by the National Institute of Mental Health (NIMH) as an illness that involves the body, mood and thoughts. It encompasses feelings of overwhelming sadness and despair that persist or intensify over time.

Description

Occasional feelings of unhappiness or sadness are normal, but when such feelings dominate everyday life causing physical and mental deterioration, they are termed depressive disorders. In Caring For The Mind, The Comprehensive Guide to Mental Health, Dianne and Robert Hales state that comparing everyday blues to clinical depression is like comparing a cold to pneumonia. Nearly 19 million American adults, approximately 10% of the population, suffer from depression in any given year. Less than one of three of these will ever pursue, or receive, medical care. In a survey conducted by the National Mental Health Association, it was found that nearly half of those surveyed believed that depression was not an illness, but rather a personal emotional weakness. However depressive disorders are valid illnesses that require treatment and can literally be life-threatening: Fifteen percent of all people diagnosed as being depressed actually do commit suicide. Thirty percent may make unsuccessful attempts.

Categories of depression include:• major depression

• seasonal affective disorder
• bipolar disorder
• dysthymia
• depression due to a general medical condition
• postpartum depression
• substance-induced depression

Major depression

Heredity appears to be strongly linked to major depression. As a rule, the rate of depression between family members of a person suffering from major depression is one to three times higher than in families where there is none. An identical twin is 66% more likely to become depressed if the other develops the illness. However therapists can often see predictable patterns of behavior that lead to depression. Life traumas such as grief also seem to lead to major depression.

Seasonal affective disorder (SAD)

The unique characteristic of SAD is when the depression occurs. Incidences usually occur at a specific time each year. SAD can be either unipolar, showing depressive symptoms only, or bipolar, having cycles of depression and elevated mood. SAD typically begins in the autumn, when the days grow shorter, and continues through the winter, ending in the spring. A less common form begins in the spring and ends in early fall. The NIMH estimates that ten million Americans have SAD.

Bipolar disorder

Bipolar disorders are believed to be caused by abnormal functioning of the brain. Heredity is considered a major factor.

Dysthymia

Like other depressions, dysthymia has been related both to hereditary chemical imbalances within the brain and to traumatic events in life, often going back to childhood. Some research has linked dysthymia to attention deficit hyperactivity disorder (ADHD) and conduct and personality disorders.

Depression due to a general medical condition

Among the physical illnesses capable of causing depression are cancer, heart disease, hormonal problems (such as thyroid disorders), Alzheimer's and Parkinson's Disease, brain tumors, head injuries, infectious illnesses, and malnutrition/vitamin deficiency.

Postpartum depression

This type of depression appears related to changes in hormonal chemistry that affects a woman's brain chemistry.

Substance-induced depression

Among the substances that are capable of causing depression are:

• alcohol
• minor tranquilizers such as valium
• heroin and other narcotics
• antihistamines
• anticancer drugs
• steroids and corticosteroids
• anti-seizure medications such as dilantin or depakot
• anti-inflammatory drugs
• cocaine, when its initial elevation in mood has passed
• estrogen
• L-dopa, a drug used to treat Parkinson's disease

Causes and symptoms

As study of the brain and nervous system has advanced, it has become known that depression is a complicated biological process that interrupts the normal balance of neurotransmitters, or messenger chemicals such as norepinephrine or serontin.

Seasonal affective disorder

SAD is common in northern climates. It is nearly nine times more prevalent in New Hampshire as in Florida, indicating that the altered brain chemistry that produces the depression is related to the decrease in light in northern climates during the winter. However, the cause of SAD is still under investigation.

Diagnosis

Many people go to their primary care practitioner with complaints of insomnia, lack of appetite, or other physical complaints only to discover that what they actually have is depression. A thorough physical examination is needed, including a family history of depression, the person's use of alcohol or other drugs, and medications being taken. Psychological testing and a mental status examination may be conducted. Several clinical inventories or scales may be used to assess a patient's mental status and determine the presence of depressive symptoms. Among these tests are: the Hamilton Depression Scale (HAM-D), Child Depression Inventory (CDI), Geriatric Depression Scale (GDS), Beck Depression Inventory (BDI), and the Zung Self-Rating Scale for Depression. These tests may be administered in an outpatient or hospital setting by a general practitioner, nurse, social worker, psychiatrist, or psychologist. The guidelines for diagnosing depression are found in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).