Home > Encyclopedia of Nursing & Allied Health > Depressive Disorders

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

Major depression can be mild, moderate or severe, and the rating of its severity is based upon the number of symptoms the person has, and how seriously these symptoms affect their lives. Typical symptoms are:

• lack of interest in once-enjoyable activities
• loss or gain of weight
• difficulty concentrating or making decisions
• feelings of worthlessness and hopelessness
• changes in sleep patterns, either insomnia or hypersomnia

People with major depression may be preoccupied with death or suicide. In children, it may manifest itself as irritability or acting out. According to the National Comorbidity Survey, major depression is the single most common mental illness in the United States, affecting one in ten Americans, and women twice as often as men. Ten to 15% of people over 65 and 25% of those in nursing homes show symptoms, and NIMH estimates that better than half of elderly Americans who suffer from major depression do not receive appropriate treatment.

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

Close to two million Americans are diagnosed as having bipolar disorder, or manic depression, a mental illness that is characterized by cycles of giddy elation and despondency. Approximately one-fifth of all depressive disorders are termed bipolar. People suffering from bipolar illnesses often first exhibit hypomania, a mild state of mania, in which they are often able to accomplish a great deal, go without sleep, and exhibit extreme self-confidence. As the disease progresses, they may cycle into full-blown mania, and engage in much more dangerous behavior, such as wild spending sprees, promiscuous sexual activity, substance abuse, and other self-destructive behaviors. This euphoric phase is followed by the depths of classic depression.

Dysthymia

Dysthymia, or chronic mild depression, has been described as sadness that will not end. There has been debate among mental health professionals for several years as to whether dysthymia is a truly separate entity from major depression, and the answer remains unclear. NIMH studies have shown that three-quarters of those diagnosed woth dysthymia also had other disorders, including major depression, panic or anxiety disorders, and substance abuse. The National Comorbidity Survey suggested that approximately 6% of Americans will develop this disorder in their lifetimes.

Depression due to a general medical condition

Many people are not aware that physical disease can cause depression. One of the significant differences in this type of depression is that patients continue to feel good about themselves, and complain that the depression is interfering with their normal life activities.

Postpartum depression

It is not unusual for a new mother to have what is termed baby blues shortly after giving birth. This involves feeling sadder than usual, crying easily, and typically occurs in the first seven to 10 days after birth. However, about 1% of all new mothers develop a true mental illness, postpartum depression, between a month and a year after giving birth. The symptoms are similar to major depression, but some women may develop more serious complications, including hallucinations and delusions.

Substance-induced depression

Many different medications, both legal and illegal, can cause depression. Alcoholism has long been linked closely with depression, but it is now known that one in four alcoholics suffered from depression before they ever drank, and will remain depressed whether they drink again or not, unless the depression is treated.

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.

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 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.

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

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).

Treatment

Major depression, dysthymia, and seasonal affective disorder are all treated effectively with psychosocial therapy of various kinds and antidepressant medications.

Antidepressants

Antidepressant medications, without any other type of treatment, are estimated to relieve the symptoms of 60–70% of clinically depressed people. Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (Prozac) and sertraline (Zoloft) reduce depression by increasing levels of serotonin, a neurotransmitter. Some clinicians prefer SSRIs for treatment of dysthymic disorder. Anxiety, diarrhea, drowsiness, headache, sweating, nausea, poor sexual functioning, and insomnia are all possible side effects of SSRIs.

Tricyclic antidepressants (TCAs) are older and less expensive medications than SSRIs, but they have more severe side effects, including persistent dry mouth, sedation, dizziness, and irregular heartbeat. Because of these, caution is taken when prescribing TCAs to elderly patients. TCAs include amitriptyline (Elavil), imipramine (Tofranil), and nortriptyline (Aventyl, Pamelor). A 10-day supply of TCAs is potentially lethal, so these drugs are questionable treatment options for patients at risk for suicide.

Monoamine oxidase inhibitors (MAOIs) such as tranylcypromine (Parnate) and phenelzine sulfate (Nardil) block the action of monoamine oxidase, a central nervous system enzyme. Patients taking MAOIs must restrict foods high in tyramine (found in red wine, aged cheeses, and meats) from their diet to avoid potentially serious hypertension.

Heterocyclics include bupropion (Wellbutrin) and trazodone (Desyrel). Bupropion should not be prescribed for patients with seizure disorder. Side effects of the drug may include agitation, anxiety, confusion, tremor, dry mouth, fast or irregular heartbeat, headache, low blood pressure, and insomnia. Because trazodone has a sedative effect, it is useful in treating depressed patients with insomnia.

Psychosocial therapy

Psychotherapy explores an individual's life to bring to light possible contributing causes of the present depression. During treatment, the therapist facilitates an awareness of thought patterns and how they developed. There are several different subtypes of psychotherapy, but all have the common goal of helping the patient develop healthy problem solving and coping skills.

Electroconvulsant therapy

ECT, or electroconvulsive therapy, is normally employed after other treatment options have been explored. But it may be used sooner if severe depression, suicide risk, or psychosis is present, or if the person is unable or unwilling to take medication. About half of those who do not improve from other therapies recover after having ECT.

The treatment consists of a series of electrical pulses that move into the brain through electrodes on the patient's head. ECT is given under general anesthesia and patients are administered a muscle relaxant to prevent convulsions. Although the exact mechanisms behind the success of ECT therapy are not known, it is believed that the electrical current modifies the electrochemical processes of the brain, consequently relieving depression. Headaches, muscle soreness, nausea, and confusion are possible side effects immediately following ECT. Memory loss, typically transient, is reported by ECT patients.

Phototherapy

Phototherapy, or exposure to fluorescent light bulbs installed in a metal box with a plastic screen ten to twenty times brighter than indoor lighting, has proven effective in treating SAD. Phototherapy is often combined with other treatments such as medication or psychosocial therapy. The person sits in front of this light box for anywhere from one-half hour to two hours.

Alternative treatment

St. John's wort (Hypericum perforatum) is used throughout the world to treat depression. In Germany, St. John's Wort is the most widely used antidepressant. This herbal antidepressant has few reported side effects, but some users have experienced high blood pressure, headaches, stiff neck, nausea, and vomiting. NIMH is currently involved in a three-year study of its efficacy. However, in February 2000, a public health advisory was issued by the Food and Drug Administration (FDA) stating that St. John's wort may interact with other medications commonly prescribed for heart disease, depression, seizures, and certain cancers, as well as anti-rejection drugs used for transplant patients. Healthcare providers were advised to alert their patients to the risk of this interaction.

Holistic treatment can also be very therapuetic in treating depression. Good nutrition, proper sleep, exercise, and full engagement in life are very important to a healthy mental state.

Prognosis

Untreated or improperly diagnosed depression is the number one cause of suicide in the United States. Yet treatment can result in dramatic improvement for between 75–80% of patients, and should be clearly evident within three to four months. Five to 10% of patients still report depression two years after initially being treated, but there are varying reasons for this, including medication noncompliance and alcohol abuse. The risk of recurrence climbs significantly with each episode.

Prevention

Education is crucial for patients with depressive disorders. They must learn to recognize symptoms and to take an active part in their treatment. Extended maintenance treatment with antidepressants may be required in some patients to prevent relapse. Physical exercise and staying connected to self-help support groups have both been shown to be effective in preventing depression. Early intervention with children with depression is effective in arresting development of more severe problems.

Health care team roles

Psychiatrist

Psychiatrists are licensed medical doctors who have undergone a three-year psychiatric residency. They diagnose depression, determine appropriate treatment, and provide psychotherapy and support for patients.

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KEY TERMS

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Clinical depression—Depression that is serious enough to require psychiatric intervention and treatment.

Hypersomnia—The need to sleep excessively; a symptom of dysthymic and major depressive disorder.

Neurotransmitter—A chemical in the brain that transmits messages between neurons, or nerve cells. Changes in the levels of certain neurotransmitters, such as serotonin, norepinephrine, and dopamine, are thought to be related to depressive disorders.

Psychomotor agitation—Disturbed physical and mental processes (fidgeting, wringing of hands, racing thoughts); a symptom of major depressive disorder.

Psychomotor retardation—Slowed physical and mental processes (slowed thinking, walking, and talking); a symptom of major depressive disorder.

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Education on the nature of depression, and the various treatment options available, are important adjuncts to the therapy they provide.

Primary care practitioner (PCP)

Though depression is a mental illness, depression may be diagnosed by primary care practitioners because depressed patients often exhibit distinct physical symptoms. Psychiatrists frequently become involved only after a consultation is requested. The importance of a psychiatric referral for further evaluation cannot be overstated. It can literally save a severely depressed person's life.

Registered nurse (RN), psychiatric nurse, or licensed practical nurse (LPN)

Both RNs and LPNs must complete a prescribed nursing course and pass a state examination. RNs typically have a degree in nursing, and psychiatric nurses have additional training specific to their field. Both RNs and LPNS are the health care team members who are most involved with depressed patients in outpatient clinics and in psychiatric units, where patients at risk for suicide must be monitored. Observational skills, empathy, and the ability to listen are necessary assets for nurses. Education about depression typically comes from both physicians and nurses.

Social workers

Social workers are usually either certified (CSW) or licensed clinical social workers (LCSW). A two-year graduate degree, specialized training that includes supervised clinical work with the mentally ill, and state licensure are typical requirements. Social workers often conduct supportive groups or programs that help people vent feelings or work on ways to better be able to cope.

Mental health assistants

These are staff members on inpatient psychiatric units who have been provided with special training in order to assist with the care of people with mental illness. They normally aid patients with day-to-day needs, accompany them to appointments or for walks if necessary, help deal with crises, and assist professional staff in providing care.

Joan M. Schonbeck