What Is Depression?
Depression may be described as feeling sad, blue, unhappy, miserable or down in the dumps. Most of us feel this way at one time or another for short periods. But true clinical depression is a mood disorder in which feelings of sadness, loss, anger or frustration interfere with everyday life for an extended time.
Depression is a common condition. The National Institute of Mental Health (NIMH) estimates that about 10 percent of American adults experience some form of depression. For people with chronic illnesses, the number can be higher. For example, NIMH estimates that about 25 percent of people with cancer have depression, and one study of people with multiple sclerosis found that 41.8 percent had significant symptoms of depression.
The symptoms of depression can be mild, moderate or severe. But even when symptoms are mild, the condition is not the same as temporarily having the blues. People cannot snap out of depression by force of their will. And while practicing healthy habits may help, getting regular exercise, eating right or taking a vacation may not completely alleviate depression.
Depression is more common in women than men and is especially common during the teen years. Men seem to seek help for feelings of depression less often than women. Therefore, women may only have more documented cases of depression.
What Causes Depression?
Depression often runs in families and may be due to heredity, learned behavior or both. Even with a genetic predisposition, it is usually a stressful or unhappy life event that triggers the onset of a depressive episode. While the exact causes of depression are unknown, several factors appear to affect its onset:
- Biochemistry: Nerve cells in the brain send and receive messages that control your emotions and feelings, with the help of chemicals called neurotransmitters. Scientists believe that depression symptoms occur when some of these neurotransmitters, including serotonin and norepinephrene, are not delivered correctly, causing a chemical imbalance.
- Genetics: A family history of depressive disorder puts people at greater risk, but depression also strikes people who have no family members with the illness. Depression that results from a person's biology or genetic inheritance is sometimes referred to as endogenous depression.
- Personality: People who are pessimistic or have low self-esteem or low tolerance for stress are more likely to develop depression.
- Difficult life situations: Depression may be more likely in people who are facing serious problems in their lives, such as abuse, violence or poverty. Difficult times, such as divorce, the death of a loved one, financial problems or moving from your home can also contribute to depression. This type of depression is sometimes referred to as reactive depression.
- Other illnesses: People who have certain other medical conditions – such as cancer, heart disease, stroke, diabetes, Parkinson's disease and hormonal disorders – are more likely to develop depression.
Depression may also be brought on by:
- Disappointment at home, work, or school (in teens, this may be breaking up with a boyfriend or girlfriend, failing a class or parents divorcing)
- Drugs such as sedatives and high blood pressure medications
- Alcohol or drug abuse
- Chronic stress
- Childhood events like abuse or neglect
- Social isolation (common in the elderly)
- Nutritional deficiencies (such as folate and omega-3 fatty acids)
- Sleeping problems
What Are the Symptoms of Depression?
Not everyone who is diagnosed with depression has the same symptoms. Some experience only a few symptoms, others have most of them. How severe the symptoms are and how long they last also varies from person to person. To be diagnosed with major depression, a person must have at least five of the following symptoms nearly every day for at least two weeks:
- Feeling sad or empty
- Decreased interest or pleasure in activities
- Appetite change with weight loss or weight gain
- Decreased or increased sleeping
- Fatigue or loss of energy
- Feeling worthless or guilty
- Being either agitated or slowed down
- Difficulty thinking or concentrating
- Recurrent thoughts of death or suicide
Low self-esteem is common with depression, so are sudden bursts of anger and lack of pleasure from activities that normally make you happy, including sex.
Depressed children may not have the classic symptoms of adult depression. Watch especially for changes in school performance, sleep and behavior. If you wonder whether your child might be depressed, it's worth bringing to a doctor's attention.
Are There Different Types of Depression?
As with other types of illness, depression takes different forms. Some of the most common depressive disorders are:
- Major depression is characterized by symptoms that affect a person's work, sleep, eating habits, and interest in activities he or she once enjoyed. Episodes of major depression can last for six months or more. To be diagnosed with major depression, a person must have several of the symptoms noted in question 3 LINK on most days for at least two weeks. People with major depression may have just one episode of the illness, but more often the symptoms return several times during their lifetime.
- Dysthymia is a low-intensity mood disorder characterized by similar but less severe symptoms than major depression, but the condition is longer-lasting (the symptoms must be present for two years to receive the diagnosis). While not totally disabling, dysthymia makes it difficult for a person to feel good or function normally. Many people who have dysthymia also have periods of major depression.
- Bipolar disorder, which is sometimes called manic-depressive illness, is much less common than other types of depressive disorders. It is marked by cycles of intense highs, called manias, followed by intense lows, or depressions.
Other common forms of depression include:
- Postpartum depression is depression after the birth of a baby. Between 10 and 15 percent of women who give birth are clinically diagnosed with this form of depression. (Postpartum psychosis, which is sometimes confused with postpartum depression in the media, is a rarer and much more serious mood disorder that requires immediate medical care.)
- Premenstrual dysphoric disorder (PMDD) refers to depressive symptoms that occur about one week prior to menstruation and disappear after you menstruate.
- Seasonal affective disorder (SAD) occurs during the fall-winter season and disappears during the spring-summer season. It's likely due to lack of sunlight.
How Do I Get Help for Depression?
Without treatment, depression can be extremely serious, and even life-threatening if a person has thoughts of suicide, so it's extremely important to seek help if you are having depression symptoms. Effective treatments are available, and the National Institute of Mental Health estimates that more than 80 percent of people who seek treatment find relief from their symptoms.
If you are depressed for two weeks or longer, contact your doctor about treatment options or referral to a professional who is knowledgeable about depression, such as a psychotherapist or a psychiatrist.
If you have thoughts of suicide, a suicidal plan or thoughts of harming yourself or others, call 911 or a suicide hotline, or go to a nearby emergency room.
Call your doctor right away if:
- You hear voices that are not there.
- You have frequent crying spells with little or no provocation.
- You have had feelings of depression that disrupt work, school or family life for longer than two weeks.
- You have three or more depressive symptoms.
- You think that one of your current medications may be making you feel depressed. DO NOT change or stop any medications without consulting your doctor.
- You believe that you should cut back on drinking or drugs, a family member or friend has asked you to cut back, you feel guilty about the amount of alcohol or drugs you use, or you drink alcohol or use drugs first thing in the morning.
How Is Depression Diagnosed?
Because some medicines and medical conditions can cause the same symptoms as depression, the first step in diagnosis is a complete medical history and a thorough physical examination. The exam may include an interview and laboratory tests to rule out other causes for the symptoms. If no other cause is found, people with symptoms of depression usually undergo a psychological evaluation performed by their physician or by a psychologist or psychiatrist.
During a diagnostic psychological examination, the doctor asks a series of questions, including:
- What are your symptoms?
- How long have you had these symptoms?
- How severe are the symptoms?
- Have you had these symptoms before?
- If so, were you treated for depression?
- What treatments did you have and which worked best?
- Do you have any relatives who have had depression?
- If so, were the relatives treated for depression, and which treatments worked best?
- Do you use drugs or drink alcohol?
- Have you thought about death or suicide?
- Whether speech or thought patterns or memory have been affected.
- Other associated symptoms (sleep, appetite, concentration, energy).
- Possible stressors in your life, and support systems in place.
If your answers to these questions indicate that you have depression, your doctor will work with you on a treatment plan.
What Medications Are Used to Treat Depression?
Doctors can choose from several different types of anti-depressants (sometimes combined with psychotherapy) based on a person's symptoms and tolerance for the medication. Because they are unable to tell how well a person will respond to an anti-depressant in advance, a person may need to try several different medications or combinations of medications to alleviate symptoms.
It takes six to eight weeks for most people to feel the full effect of anti-depressant medication, and most are prescribed for six months to a year, and sometimes longer. People with chronic major depression may need to take anti-depressants indefinitely. A person with depression should never stop taking anti-depressants without first talking to a doctor.
The major types of anti-depressant medications are:
- Selective serotonin and norepinephrine reuptake inhibitors (SSNRIs): The newest types of anti-depressants work by acting on two chemical messengers in the brain linked to depression, norepinephrine and serotonin. Medications in this category include Cymbalta (duloxetine), Effexor (venlafaxine) and Serzone (nefazodone).
- Selective serotonin reuptake inhibitors (SSRIs): SSRIs work by increasing the activity of serotonin in the brain. They include Prozac (fluoxetine), Zoloft (sertraline), Luvox (fluvoxamine), Paxil(paroxetine), Celexa (citalopram) and Lexapro (escitalopram).
- Tricyclics: Like SSNRIs, tricyclic anti-depressants work on norepinephrine and serotonin. They are as effective in treating depression as the newer drugs, but their side effects are usually more severe. As a result, doctors do not often prescribe them as a first choice. Tricyclic medications include Tofranil (imipramine), Elavil ( amitriptyline), Pamelor (nortriptyline) and Norpramin (desipramine).
- Monoamine oxidase inhibitors (MAOIs): MAOIs work by blocking the action of a chemical substance called monoamine oxidase (MAO) in the nervous system. Doctors sometimes prescribe these medications when people do not respond to other types of anti-depressants. They are also prescribed for panic disorder and bipolar disorder. Medications in this group include Nardil ( phenelzine), Parnate (tranylcypromine) and Marplan (isocarboxazid).
What Other Treatments Are Available for Depression?
Depression is treated in a variety of ways.
People with mild depression may only need psychotherapy (talk) to improve their symptoms, though doctors often advise therapy in conjunction with medication. Psychotherapy attempts to help people work through their problems by talking regularly with a therapist. Depending on the situation, a person may undergo psychotherapy one-on-one with a therapist, take part with a spouse or family or try group therapy with people who have similar problems.
Research has shown that some one-on-one short-term therapies, lasting 10 to 20 weeks, can help with depression. They are:
- Interpersonal therapy, which focuses on improving personal relationships that help cause depression or make it worse.
- Cognitive or behavioral therapy, which focuses on changing negative thinking and behavior that may be linked to depression.
For people who are so severely depressed as to be unable to function, or who are suicidal and cannot be safely cared for in the community, psychiatric hospitalization may be necessary.
Electroconvulsive therapy (ECT)
Doctors may suggest ECT for people with severe depression, and for those who either cannot take anti-depressants or for whom anti-depressants do not work. ECT is performed under sedation and muscular paralysis to eliminate discomfort, and uses a brief electrical shock to cause a short seizure – about 30 seconds – in the brain. Doctors think it works for depression because the seizure releases chemical messengers in the brain, such as norepinephrine and serotonin. Usually, a person needs 12 or fewer treatments.
One such herbal remedy is St. John's wort (Hypericum perforatum). In Germany, St. John's wort has long been used to treat mild to moderate depression. Studies on its use there, however, have been short-term and have not usually used uniform doses.
The U.S. National Institutes of Health conducted a three-year study of St. John's wort and major depression of moderate severity. The study found no significant difference in rate of response for depression among groups receiving St. John's wort, taking an SSRI anti-depressant or those getting a placebo. People who took the anti-depressant, however, reported better overall functioning than those who took either the St. John's wort or the placebo.
If you are using herbal treatments for depression or other conditions, you should always tell your doctor what you are taking since the herbal treatments may interact with other medications.
Can Depression Be Prevented?
Healthy lifestyle habits can help prevent depression, or lessen the chances of it happening again. Regardless of whether you have mild or major depression, the following self-care steps are recommended:
- Get enough sleep.
- Follow a healthy, nutritious diet.
- Exercise regularly.
- Avoid alcohol, marijuana and other recreational drugs.
- Get involved in activities that make you happy, even if you don''t feel like it.
- Spend time with family and friends.
- Try talking to clergy or spiritual advisors who may help give meaning to painful experiences.
- Consider prayer, meditation, tai chi or biofeedback as ways to relax or draw on your inner strengths.
- Add omega-3 fatty acids to your diet, which you can get from cold-water fish like tuna, salmon or mackerel.
- Take folate (vitamin B9) in the form of a multivitamin (400 to 800 micrograms).
- Try light therapy using a special lamp that mimics the sun for seasonal affective disorder.
- Get counseling during times of grief, stress or low mood. Family therapy may be particularly important for teens who feel blue.
Where Can I Get More Information on Depression?
You can find the latest news about depression and bipolar disorder on these Everyday Health pages:
If you are writing a depression research paper and you don't feel quite sure where to begin, the following are some topics which you may want to consider including in your paper. Links are included to relevant articles on the Verywell.com Depression site which will help you gather basic information for your paper; and, hopefully, trigger some ideas for topics which you can research further in the library and elsewhere on the Internet.
Unfortunately, I cannot grant personal interviews to students who are writing research papers. You should, however, have plenty of good ideas for what you would like to include in your research paper after looking over this list of topics.
1. What Is Depression?
Everyone experiences times when they feel a little bit blue or sad. This is a normal part of being human. Depression, however, is a medical condition which is quite different from everyday moodiness.
2. What Types of Depression Are There?
There are several different types of depression, depending upon how an individual's depression symptoms manifest themselves. Depression symptoms may vary in severity or in what is causing them. They may also be part of an illness called bipolar disorder, which includes fluctuations between depression and a state of extreme elation called mania.
3. What Causes Depression?
The possible causes for depression are many and not yet well understood. However, it is most likely that depression results from an interplay of genetic vulnerability and environmental factors.
4. Who Is at Risk for Depression?
Certain risk factors may make a person more prone to developing depression, such as a family history of depression, adverse childhood experiences, stress, illness and being female.
This is not a complete list of all risk factors, however, it's a good place to start.
5. What Are the Signs and Symptoms of Depression?
The signs of depression are those outward manifestations of the illness that a doctor can observe when she examines a patient, for example, a lack of emotional responsiveness. On the other hand, symptoms are those subjective things about the illness that only the patient can observe, such as feelings of guilt or sadness. In an illness such as depression, which is often invisible to the outside observer, it is very important for patients to make an accurate accounting of all of their symptoms so that their doctor can diagnose them properly.
6. How Is Depression Diagnosed?
In some ways, the diagnosis of depression is more an art than a science. Doctors must generally rely upon the patient's set of symptoms and what they can observe about him during their examination in order to make a diagnosis. While there are certain laboratory tests which can be performed to rule out other medical illnesses as a cause of depression, there is not yet a definitive test for depression itself.
7. How Is Depression Treated?
The first choice for depression treatment is generally an antidepressant medication, with selective serotonin reuptake inhibitors (SSRIs) being the most popular choice due to them being quite effective and having relatively fewer side effects than certain older antidepressants. Psychotherapy, or talk therapy, is another effective and popular choice. It is especially efficacious when combined with antidepressant therapy. Certain other treatments, such as electroconvulsive therapy (ECT) or vagus nerve stimulation (VNS), are most commonly used for patients who do not respond to the other two.
Ferri, Fred F. Ferri's Clinical Advisor 2009. 1st ed. Philadelphia: Mobsy, 2009.
Moore, David P. and James W. Jefferson, eds. Handbook of Medical Psychiatry 2nd ed. Philadelphia: Mosby Elsevier, 2004.