Depression Differences
There are many different faces of depression, not only because the condition is so widespread, but also because it can manifest in various ways. For one thing, different people may experience different symptoms of depression—from feelings of sadness, hopelessness or guilt to fatigue, trouble concentrating, agitation, or a loss of interest or pleasure in normal activities. 
Complicating matters, there are several different types of depression, many of which exist along a spectrum depending on the duration and severity of symptoms.
"The good news is, there has been a significant increase in the number of people being treated for depression," says Christopher Beevers, Ph.D., an assistant professor of psychology and director of the mood disorders laboratory at the University of Texas at Austin. "The bad news is that still roughly half of people with a diagnosable form of depression are not receiving treatment." What's more, researchers at Harvard Medical School have found that treatment for major depression is adequate in only 42% of cases.
Who's At Risk for Depression
Many different types of depression share common risk factors. If you have a first-degree relative (e.g., mother, father, sibling) who has suffered from depression, your risk of developing the disorder is two to three times higher than someone who doesn't have such a family history, notes Kenneth Kendler, M.D., Banks distinguished professor of psychiatry and professor of human genetics at Virginia Commonwealth University in Richmond. Meanwhile, women have a similarly elevated risk. "For every category of depression, women predominate," says Carol Landau, Ph.D., a clinical professor of psychiatry and medicine at the Alpert Medical School, Brown University, and author of The New Truth About Menopause. "Some people say it's because women go to doctors more but it's also the way people think: A lot of women ruminate [think very deeply about things], which can set you up for major or mild depression."
Whether they're caused by genetic, biochemical, environmental, or psychological factors, here's how several different types of depression stack up:
Major Depression: Seriously Down in the Dumps
If you feel sad or down for most of the day, nearly every day, or you stop getting pleasure from your usual activities, and this has been going on for at least 2 weeks, you may have major depression.
- changes in eating or sleeping habits
- lack of energy
- feelings of worthlessness or excessive guilt
- agitation
- trouble concentrating or making decisions
- feeling empty or irritable
- thinking about your own death or suicide
Other symptoms can include:
To be considered "major depression" five or more of these symptoms must be present; with fewer, it may be considered "subclinical depression." "Once you've had one episode of major depression, there's a 50% chance it'll happen again," Landau says.
Talk therapy—such as cognitive behavioral therapy (CBT)—and medications are the primary treatments for major depression. Among the newer types of antidepressants are the selective serotonin reuptake inhibitors (SSRIs such as fluoxetine and sertraline), which increase the availability of the neurotransmitter serotonin in the brain, and the serotinin-norepinephrine reuptake inhibitors (SNRIs such as venlafaxine and duloxetine), which enhance norepinephrine and serotonin levels in the brain. The older tricyclic antidepressants (like tofranil and amitriptyline) and MAO inhibitors (like phenelzine and selegiline) are also options, but often have more side effects or dietary restrictions.
With all antidepressants, it can take up to 4 weeks for the full therapeutic effects to kick in. "With regular major depression, two-thirds to three-quarters of people who are treated with either CBT or antidepressants will feel better within 3 to 4 months," Beever says. With chronic depression, which can persist for years, a combination of antidepressants and CBT has been found to be particularly effective.
For depression of any length, lifestyle can also have an impact. "Managing stress, setting limits, getting enough sleep, and exercising regularly are really important for people with depression," Landau says. "Exercise can be extremely helpful, and there are no side effects."
Dysthymia: The Eeyore Syndrome
Because dysthymia is a chronic but less severe form of depression that's present for at least 2 years, some people think this is just the way they are (low in energy) or part of their personality (gloomy). "Although millions of people suffer from dysthymia, most don't know it," says Michael Thase, M.D., a professor of psychiatry at the University of Pittsburgh School of Medicine and coauthor of Beating the Blues: New Approaches to Overcoming Dysthymia and Chronic Mild Depression. "It is one of the most under-recognized and under-treated mood disorders because it creeps in so insidiously that people often don't notice anything is wrong. They simply come to accept life through a gray-tinted lens." But dysthymia can increase a person's chances of developing substance abuse, heart disease, stroke, and compromised immune function, Dr. Thase notes. Plus, someone with dysthymia is at risk for developing major depression on top of it—what’s often called "double depression."
For dysthymia alone, "there’s less scientific evidence regarding the efficacy of antidepressants," says Andrew Winokur, M.D., Ph.D., a professor of psychiatry and director of psychopharmacology at the University of Connecticut Health Center in Farmington. "Cognitive-behavioral therapy or interpersonal therapy [which focuses on improving relationships] is often considered the first-line choice with the possibility that adding in an antidepressant might be helpful for some individuals."
Seasonal Affective Disorder: A Bad Case of The Winter Blues
Some people feel slightly blue or lethargic during the winter months—a condition often referred to as the winter blues. But during the winter (and sometimes fall) months, up to 10% of people in the United States feel consistently down, experience low energy or apathy, sleep more than usual, have increased food cravings (especially for carbohydrates) and gain weight, and suffer reduced concentration to the point where it affects their ability to function; these people have seasonal affective disorder (SAD).
Light therapy—in which you sit under a special light device that emits 10,000 lux for 30 minutes per day—can significantly improve symptoms for up to 70% of those with SAD, according to Raymond Lam, M.D., professor of psychiatry at the University of British Columbia in Vancouver, Canada. Taking antidepressants—such as SSRIs—throughout the troublesome season can also help. In a study involving 96 people with SAD, researchers at four Canadian health centers found that light treatments and antidepressants were equally effective at reducing symptoms, though the light therapy produced an earlier response; those who used light therapy began to feel better after just 1 week. Some SAD-sufferers also find it helpful to increase the amount of light in their homes and offices and to exercise outdoors regularly—by taking a brisk walk at noon, for example—during the winter.
