Everyone feels sad or blue sometimes.

It is a natural part of life. But when the sadness persists and interferes with everyday life, it may be depression. Depression is not a normal part of growing older. It is a treatable medical illness, much like heart disease or diabetes.

Depression is a serious illness affecting approximately 15 out of every 100 adults over age 65 in the United States. The disorder affects a much higher percentage of people in hospitals and nursing homes. When depression occurs in late life, it sometimes can be a relapse of an earlier depression. But when it occurs for the first time in older adults, it usually is brought on by another medical illness. When someone is already ill, depression can be both more difficult to recognize and more difficult to endure.

Depression is not a passing mood.

Sadness associated with normal grief or everyday "blues" is different from depression. A sad or grieving person can continue to carry on with regular activities. The depressed person suffers from symptoms that interfere with his or her ability to function normally for a prolonged period of time.

Recognizing depression in the elderly is not always easy. It often is difficult for the depressed elder to describe how he or she is feeling. In addition, the current population of older Americans came of age at a time when depression was not understood to be a biological disorder and medical illness. Therefore, some elderly fear being labeled "crazy," or worry that their illness will be seen as a character weakness.

The depressed person or their family members may think that a change in mood or behavior is simply "a passing mood," and the person should just "snap out of it." But someone suffering from depression can not just "get over it." Depression is a medical illness that must be diagnosed and treated by trained professionals. Untreated, depression may last months or even years.

Untreated, depression can:

• lead to disability
• worsen symptoms of other illnesses
• lead to premature death
• result in suicide.

When it is properly diagnosed and treated, more than 80 percent of those suffering from depression recover and return to their normal lives.

The most common symptoms of late-life depression include:

• persistent sadness (lasting two weeks or more)
• feeling slowed down
• excessive worries about finances and health problems
• frequent tearfulness
• feeling worthless or helpless
• weight changes
• pacing and fidgeting
• difficulty sleeping
• difficulty concentrating
• physical symptoms such as pain or gastrointestinal problems.

One important sign of depression is when people withdraw from their regular social activities. Rather than explaining their symptoms as a medical illness, often depressed persons will give different explanations such as:

"It's too much trouble,"

"I don't feel well enough," or

"I don't have the energy."

For the same reasons, they often neglect their personal appearance, or may begin cooking and eating less. Like many illnesses, there are varying levels and types of depression. A person may not feel "sad" about anything, but may exhibit symptoms such as difficulty sleeping, weight loss, or physical pain with no apparent explanation. This person still may be clinically depressed. Those same symptoms also may be a sign of another problem -- only a doctor can make the correct diagnosis.

It can happen to anyone.

Sometimes depression will occur for no apparent reason. In other words, nothing necessarily needs to "happen" in one's life for depression to occur. This can be because the disease often is caused by biological changes in the brain. However, in older adults, there usually are understandable reasons for the depression.

As the brain and body age, a number of natural bio-chemical changes begin to take place. Changes as the result of aging, medical illnesses or genetics may put the older adult at a greater risk for developing depression.

Life changes

Chronic or serious illness is the most common cause of depression in the elderly. But even when someone is struggling with a chronic illness such as arthritis, it is not natural to be depressed. Depression is defined as an illness if it lasts two weeks or more and if it affects one's ability to lead a normal life.

Many factors can contribute to the development of depression. Often people describe one specific event that triggered their depression, such as the death of a partner or loved one, or the loss of a job through layoff or retirement. What seems like a normal period of sadness or grief may lead to a prolonged, intense grief that requires medical attention.

The loss of a life-long partner or a friend is a frequent occurrence in later life. It is normal to grieve after such a loss. But it may be depression rather than bereavement if the grief persists, or is accompanied by any of the following symptoms:

• guilt unconnected with the loved one's death
• thoughts of one's own death
• persistent feelings of worthlessness
• inability to function at one's usual level
• difficulty sleeping
• weight loss.

If any of these symptoms are triggered by a loss, a physician should be consulted.

Changes in the older adult's sensory abilities or environment may contribute to the development of depression. Examples of such changes include:

• changes in vision and hearing
• changes in mobility
• retirement
• moving from the family home
• neighborhood changes

Other illnesses

In the older population, medical illnesses are a common trigger for depression, and often depression will worsen the symptoms of other illnesses. The following illnesses are common causes of late-life depression:

• cancer
• Parkinson's disease
• heart disease
• stroke
• Alzheimer's disease.

In addition, certain medical illnesses may hide the symptoms of depression. When a depressed person is preoccupied with physical symptoms resulting from a stroke, gastrointestinal problems, heart disease or arthritis, he or she may attribute the depressive symptoms to an existing physical illness, or may ignore the symptoms entirely. For this reason, he or she may not report the depressive symptoms to his or her doctor, creating a barrier to becoming well.

Depression is treatable

Most depressed elderly people can improve dramatically from treatment. In fact, there are highly effective treatments for depression in late life. Common treatments prescribed by physicians include:

• psychotherapy
• antidepressant medications
• electroconvulsive therapy (ECT).

Psychotherapy can play an important role in the treatment of depression with, or without, medication. This type of treatment is most often used alone in mild to moderate depression. There are many forms of short-term therapy (10-20 weeks) that have proven to be effective. It is important that the depressed person find a therapist with whom he or she feels comfortable and who has experience with older patients.

Antidepressants work by increasing the level of neurotransmitters in the brain. Neurotransmitters are the brain's "messengers." Many feelings, including pain and pleasure, are a result of the neurotransmitters' function. When the supply of neurotransmitters is imbalanced, depression may result.

A frequent reason some people do not respond to antidepressant treatment is because they do not take the medication properly. Missing doses or taking more than the prescribed amount of the medication compromises the effect of the antidepressant. Similarly, stopping the medication too soon often results in a relapse of depression. In fact, most patients who stop taking their medication before four to six months after recovery will experience a relapse of depression.

Usually, antidepressant medication is taken for at least six months to a year. Typically, it takes four to 12 weeks to begin seeing results from antidepressant medication. If after this period of time the depression does not subside, the patient should consult his or her physician. Antidepressant drugs are not habit-forming or addictive. And because depression is often a recurrent illness, it usually is necessary to stay on the medication for six months after recovery to prevent new episodes of depression.

Electroconvulsive therapy (ECT) is a treatment that unnecessarily evokes fear in many people. In reality, ECT is one of the most safe, fast-acting and effective treatments for severe depression. It can be life saving. ECT often is the best choice for the person who has a life-threatening depression that is not responding to antidepressant medication or for the person who cannot tolerate the medication.

After a thorough evaluation, a physician will determine the treatment best suited for a person's depression. The treatment of depression demands patience and perseverance for the patient and the physician. Sometimes several different treatments must be tried before full recovery. Each person has individual biological and psychological characteristics that require individualized care.

Suicide

Suicide is more common in older people than in any other age group. The population over age 65 accounts for more than 25 percent of the nation's suicides. In fact, white men over age 80 are six times more likely to commit suicide than the general population, constituting the largest risk group. Suicide attempts or severe thoughts or wishes by older adults must always be taken seriously.

It is appropriate and important to ask a depressed person:

• Do they feel as though life is no longer an option for them?
• Have they had thoughts about harming themselves?
• Are they planning to do it?
• Is there a collection of pills or guns in the house?
• Are they often alone?

Most depressed people welcome care, concern and support, but they are frightened and may resist help. In the case of a potentially suicidal elder, caring friends or family members must be more than understanding. They must actively intervene by removing pills and weapons from the home and calling the family physician, mental health professional or, if necessary, the police.

Caring for a depressed person

The first step in helping an elderly person who may be depressed is to make sure he or she gets a complete physical checkup. Depression may be a side effect of a pre-existing medical condition or of a medication. If the depressed older adult is confused or withdrawn, it is helpful for a caring family member or friend to accompany the person to the doctor and provide important information.

The physician may refer the older adult to a psychiatrist with geriatric training or experience. If a person is reluctant to see a psychiatrist, he or she may need assurance that an evaluation is necessary to determine if treatment is needed to reduce symptoms, improve functioning and enhance well-being.

It is important to remember that depression is a highly treatable medical condition and is not a normal part of growing older. Therefore, it is crucial to understand and recognize the symptoms of the illness. As with any medical condition, the primary care physician should be consulted if someone has symptoms that interfere with everyday life. An older person who is diagnosed with depression also should know that there are trained professionals who specialize in treating the elderly (called "geriatric psychiatrists") who may be able to help.