Almost one in ten American adults experience some form of depression every year. A depressive disorder is an illness that involves the body, mood, and thoughts. It affects the way a person eats, sleeps, feels and thinks. It’s not the same as a passing blue mood, nor can people with a depressive illness merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years, but most people get better with treatment.
Three types of depressive disorders are the most common; however, within these types there are variations in the number of symptoms, their severity, and persistence. Major depression is made up of a combination of symptoms that interfere with the ability to work, study, sleep, eat, and enjoy once pleasurable activities. An episode may occur only once but more commonly occurs several times in a lifetime. Dysthymia, a less severe type of depression, has long-term, chronic symptoms that do not disable, but keep one from functioning well or feeling good. Many people with dysthymia also experience major depressive episodes at some time in their lives. Bipolar disorder, also called manic-depressive illness, is also a type of depression. Less common, bipolar disorder is characterized by cycling mood changes: severe highs (mania and hypomania) and lows (depression). Bipolar disorder is recently being viewed as a spectrum disorder, including bipolar I and bipolar II and spanning a continuum of symptoms.
Depression may have a number of complex and interacting causes. Some factors include stressful life events, such as losing a loved one, and drug or alcohol abuse. Mood disorders are sometimes caused by medical conditions, such as strokes or hypothyroidism. Certain medications are associated with depression; antihypertensives and oral contraceptives are the most frequent examples. Brain imaging shows that neural circuits that regulate moods, thinking, sleep, appetite, and behavior fail to function properly in people with depression and that critical neurotransmitters--chemicals used by nerve cells to communicate--are out of balance. The hormonal system that regulates the body's response to stress also is overactive in many depressed people. Some types of depression run in families, however, it can also occur in people who have no family history of depression. Very often, a combination of genetic, psychological, and environmental factors is involved. Later episodes of illness typically are precipitated byonly mild stresses, or none at all.
There are a variety of antidepressant medications and psychotherapies used to treat depression. People with moderate to severe depression most often benefit from antidepressants. People with bipolar disorder will take other kinds of medications, such as mood stabilzers. Some people with milder forms may do well with psychotherapy alone. In "talk therapy" a person discusses with a mental health professional the feelings, thoughts and behaviors that seem to cause difficulty in order to better understand and manage their problems. Most people with depression do best with combined treatment: medication to gain relatively quick symptom relief and psychotherapy to learn more effective ways to deal with life's problems, including depression. When psychotherapy and medications aren’t working, or are working too slowly to relieve severe symptoms, electroconvulsive therapy (ECT) may be considered. New antidepressant medications may relieve depression in hours, rather than weeks, potentially reducing the risk for suicide, which claims 30,000 lives each year.