Depression

Depression is extraordinary sadness that interferes with the ability to function.

Everyone feels sad from time to time as a natural response to disappointment and loss. Like ordinary sadness, depression may develop after a sad event or may develop for no apparent reason. Depression can also occur with many physical disorders. But depression differs from ordinary sadness in several ways. For some, depression involves a nagging sense of feeling blue that drags on as they try to perform daily activities. For others, it is a heavy shroud of despair or emotional emptiness that becomes incapacitating. And depression can and often does become life threatening when a person has a deep sense of hopelessness or worthlessness and stops eating or turns to suicide for relief.

Depression affects about 1 out of every 6 older people. Some older people have had depression earlier in their lives, whereas others develop it for the first time during old age.

Doctors have identified several types of depression. However, the symptoms that some people experience may not easily fit into any one type.

Major depression lasts at least 2 weeks, although it often lasts much longer. Some people have brief episodes of depression in reaction to certain holidays (holiday blues) or anniversaries, such as the anniversary of a loved one's death. These brief episodes are similar to major depression, but they may last only a few days.

Psychotic depression, a more severe form of major depression, is complicated by a loss of contact with reality (psychosis), which usually includes harboring false beliefs (delusions).

Seasonal affective disorder (also called a mood disability with a seasonal pattern) is depression that recurs at a certain time of the year. It typically begins in October or November and ends by February or March; thus it is sometimes referred to as autumn-winter depression. Because this type of depression usually occurs in geographic locations in which the winter is longer and harsher, experts think that a lack of sunlight may play a role.

Dysthymic disorder is a less severe type of depression that smolders and persists for at least 2 years, though often much longer. Most older people who experience dysthymic disorder do not experience major depression.

Bipolar disorder is sometimes called manic depression. Bipolar disorder involves not only depression but also periods of mania—intense joyousness and elation. Unlike younger people with bipolar disorder, in whom periods of mania tend to be more frequent and more intense than periods of depression, most older people with bipolar disorder have long periods of depression and infrequent, subtler episodes of mania. During these periods of mania, older people are often more likely to be irritable than elated.

Causes

The exact cause of depression is unknown, although imbalances of certain substances that carry messages between nerves (neurotransmitters) in the brain play an important role. An emotionally stressful life-changing event or experience precedes depression in some people. These events or experiences may include the death of a loved one, the ending of a significant relationship, or a loss of familiar surroundings, as when moving away from a long-time neighborhood. More persistent, smoldering sources of stress, such as ongoing poverty, a worsening chronic illness, a gradual loss of independence, or a lack of social support, may also contribute.

Depression sometimes develops during or soon after a person develops a physical disorder. Depression is common among people with cancer, heart attack, heart failure, hypothyroidism, or hyperthyroidism. Depression often occurs in people with nervous system and brain disorders, such as stroke, dementia, and Parkinson's disease. Depression also occurs in combination with other mental health disorders, such as anxiety.

Some drugs that older people take for physical disorders can cause symptoms of depression. These drugs include corticosteroids, digoxin, opioid analgesics, and certain drugs used to treat high blood pressure (antihypertensives), such as methyldopa and reserpine.

Abuse of alcohol or drugs, including prescription and illegal drugs, may contribute to the development of depression in some older people.

Symptoms

Extraordinary sadness is at the core of depression for many people. For others, a feeling of emptiness or absence of emotion may be the primary symptom. Many other symptoms may be present as well. Absence of pleasure or of interest in activities is often noticeable. Some depressed older people stop performing daily activities at work or at home, and they may simply stop making any effort to care for themselves. Many depressed people have trouble falling asleep and staying asleep. Early awakening in the morning is especially common. Appetite is often decreased or lost altogether.

Depression may slow thinking and interfere with concentration and memory. Some depressed older people are mistakenly thought to have dementia because of confusion, forgetfulness, and disorientation (a condition often called pseudodementia). Feelings of hopelessness, worthlessness, and guilt are common in people with pseudodementia.

Some depressed people are restless, wringing their hands and talking continuously. In contrast, other people with depression are withdrawn, seem tired all the time, move slowly, and gain weight. Symptoms may be worse at a certain time of the day, usually in the morning. Thoughts about death and suicide often surface. Many depressed people want to die or feel that they should die.

Loss of contact with reality (psychosis) develops in some severely depressed people. When this occurs, it usually involves false ideas or beliefs (delusions). For example, people with psychotic depression may become convinced that they are worthless or sinful or that they are impoverished. Some may become convinced that they hear or see people or things that no one else hears or sees (hallucinations).

People with symptoms of depression may also develop episodes of intense joyousness or elation if they have bipolar disorder. During such episodes, they may also be very restless, distracted, and irritable.

Screening and Diagnosis

Depression is often difficult to diagnose among older people, for several reasons:

• The symptoms may be less noticeable because older people may not work or may have less social interaction.
• Some people believe that depression is a weakness and are reluctant to tell anyone that they are experiencing sadness or other symptoms.
• The absence of emotion may not be interpreted as depression, but rather, as indifference.
• Family and friends may regard a depressed person's symptoms simply as evidence that the person is getting older.
• The symptoms may be attributed to another disorder.

Because recognition and diagnosis of depression can be challenging and because depression threatens a person's quality of life and ability to perform daily activities, some experts recommend screening. Screening involves asking a person a series of questions that help identify symptoms of depression. Screening for depression is offered at many community health fairs and through doctors' offices, clinics, and hospitals.

A doctor diagnoses depression by thoroughly reviewing a person's symptoms. But a physical examination and medical tests are performed to determine whether a physical disorder is causing or contributing to the person's symptoms of depression. Hypothyroidism is one of the most common of the physical disorders that causes depression. Therefore, a blood test to assess thyroid function is particularly useful.

Treatment

When a physical disorder or a drug is thought to be causing or contributing to depression, treating the disorder or reducing or stopping the offending drug may relieve the depression. However, in most instances, other treatment is needed for depression.

Depressed older people are commonly treated with drug therapy. Other treatments include counseling, electroconvulsive therapy, phototherapy, and exercise. Often a combination of therapies is best.

Drug therapy: Drug treatment with antidepressants is effective in about two thirds of depressed older people. The three types of antidepressants are selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and monoamine oxidase inhibitors (MAOIs). Other types of drugs, including psychostimulants, antipsychotics, and mood stabilizers, are available to treat certain symptoms of depression.

No one antidepressant has been found to be consistently more effective than another, although the side effects of the different types of antidepressants vary widely. Therefore, doctors usually recommend an antidepressant that is least likely to cause side effects for the person taking it.

Antidepressants usually must be taken for at least 4 weeks before they help. Occasionally, however, people respond to an antidepressant in as little as 2 weeks. If the initial dosage does not help, the doctor gradually increases the amount. If no benefit results after about 12 weeks and the dosage is as high as it can be safely increased, the doctor usually adds another drug or discontinues the first drug and switches to another.

Selective serotonin reuptake inhibitors (SSRIs) are the type of antidepressants used most often in older people. SSRIs have fewer side effects than other types of drugs used for depression. However, some SSRIs, especially fluoxetine and paroxetine, may interact with other drugs. Citalopram and escitalopram may be the least likely to cause side effects and may relieve symptoms of depression more rapidly than most other antidepressants.

Other antidepressants similar to SSRIs (both in effectiveness and side effects), such as venlafaxine, mirtazapine, and bupropion, are also often used.

Tricyclic antidepressants are used much less often for older people. Although they are effective in treating depression, they more often cause disturbing and disabling side effects.

Monoamine oxidase inhibitors (MAOIs) are a type of antidepressant that is rarely used for depressed older people because of a risk of severe side effects. Certain foods and drugs interact with MAOIs, causing high blood pressure, dizziness, headache, and fatigue.

Psychostimulants, such as methylphenidate, are an effective treatment for some symptoms of depression. If these drugs are going to work, they take effect within days rather than weeks. They are generally reserved for depressed people who are endangering themselves by not eating or drinking, because these drugs often greatly stimulate appetite. Psychostimulants may also be used to stimulate the level of energy and activity in depressed people who move very slowly and who are extremely withdrawn.

Antipsychotics are drugs that help eliminate or control symptoms of psychosis, such as delusions or hallucinations, that occur in some people with depression. Antipsychotics may be given in combination with an antidepressant, but they are typically discontinued once the antidepressant has started to take effect.

Mood stabilizers are used to treat people with bipolar disorder. These drugs help to calm some of the intense elation as well as the restlessness and irritability that occur during episodes of mania. Lithium is one such drug, but it can cause many side effects in older people. Drugs used for treating seizures, such as divalproex and gabapentin, are often better tolerated and also help stabilize mood. Tremor is a side effect of many mood stabilizers.

Counseling: Counseling (psychotherapy) is an effective treatment for mild depression. It is also effective when combined with drug therapy for more severe depression. Counseling may focus on helping the depressed person change unrealistic expectations, reduce tendencies to self-criticize, and avoid automatic reactions to negative, distorted thoughts. Counseling may also help the person use insight to distinguish between life problems that are most important and those that are minor. Problem-solving strategies may be taught so that the person is better able to cope with everyday stress. Counseling may take place in group or individual sessions. Visits are usually once a week for 12 to 20 sessions. Counseling may be performed by a specially trained social worker, a psychologist, or a psychiatrist.

Electroconvulsive therapy: Electroconvulsive therapy consists of passing an electrical current through the brain so that a seizure results. The seizure may help relieve depression by causing a release of neurotransmitters in the brain. Electroconvulsive therapy is used for people who are severely depressed, including those who have lost contact with reality (psychotic depression) and those who are a threat to themselves. Electroconvulsive therapy is also useful for people whose condition has not been helped by drug therapy. Before receiving the treatment, the person is given a drug that induces sleep (an anesthetic) and a muscle-relaxing drug to reduce the risk of injury during the seizure. Results of electroconvulsive therapy are usually felt within days. It often needs to be repeated several times.

Phototherapy: Phototherapy is the use of bright light for people with seasonal affective disorder. Phototherapy consists of sitting daily for brief periods in a room lit by a special lighting device (sometimes called a light box). Increasing the time spent outdoors may also help.

Exercise: A number of studies have pointed out the beneficial effects of exercise, particularly aerobic exercise, on mood. This may in part be due to the role of exercise in elevating the level of a type of neurotransmitter called endorphins. Endorphins are small proteins that produce a feeling of well-being and tolerance to pain by stimulating certain sites in the brain. Therefore, a supervised exercise program, perhaps combined with psychotherapy, antidepressants, or both, may be recommended.

Outlook

People with depression usually respond to treatment. However, only about one third remain free of symptoms indefinitely. Another third experience improvement with treatment but have relapses. About one third do not respond well or at all to initial treatment. Changing treatment or adding additional treatment helps some of these people. Even among those who do not respond well to treatment, the ability to function and perform daily activities usually improves somewhat.

See the sidebar When Alcohol Is a Problem.

See the sidebar Suicide and Suicidal Behavior.

See the sidebar Detecting Depression or Anxiety: At a Loss for Words.

See the table Drugs Used to Treat Depression.