About 9 percent of American adults from all walks of life suffer from some form of depression. Learn more depression facts and figures that can help you better understand this widespread condition.

According to depression statistics from the Centers for Disease Control and Prevention (CDC), about 9 percent of adult Americans have feelings of hopelessness, despondency, and/or guilt that generate a diagnosis of depression. At any given time, about 3 percent of adults have major depression, also known as major depressive disorder, a long-lasting and severe form of depression. In fact, major depression is the leading cause of disability for Americans between the ages of 15 and 44, according to the CDC. Understanding these very real depression statistics helps paint a fuller picture of the impact of depression in America.

Prevalence of Depression in Men vs. Women

According to the National Institute of Mental Health (NIMH), the largest scientific organization dedicated to mental health issues, women are 70 percent more likely than men to experience depression during the course of their lifetimes. Research has shown that this is in part due to hormones. Depression risk goes up for women after pregnancy, during menstruation, and during menopause. Another reason for higher recorded numbers among women? They are more likely to seek help and be diagnosed. “Men are more likely to try to self-medicate with drugs or alcohol, whereas women are more likely to seek help from friends and family or psychiatrists,” explains Carole Lieberman, MD, a psychiatrist, author, and member of the clinical faculty at the University of California at Los Angeles Semel Institute for Neuroscience and Human Behavior.

The Rising Rate of Depression

Statistical trends related to depression are hard to come by, but most experts agree that depression rates in the United States and worldwide are increasing. Studies show that rates of depression for Americans have risen dramatically in the past 50 years. Research published in The American Journal of Psychiatry found that major depression rates for American adults increased from 3.33 percent to 7.06 percent from 1991 through 2002. Depression is also considered a worldwide epidemic, with 5 percent of the global population suffering from the condition, according to the World Health Organization.

Depression Comes in Different Forms

“People who have stressors in their life that make them feel hopeless and helpless are more likely to become depressed,” says Dr. Lieberman. However, she notes that “there are many different types of depression, from the garden-variety sad mood to major psychotic depression.”

Major depression is defined as a severely depressed mood that goes on for two weeks or more, interfering with a person’s daily functions. Other types of depression include:

• Dysthymia. This is a type of minor but chronic depression that lasts two years or longer. Dysthymia affects about 1.5 percent of American adults.
• Postpartum depression. This form of depression affects about 10 to 15 percent of women shortly after childbirth.
• Seasonal affective disorder (SAD). This type of depression usually occurs during winter months and is probably caused by lack of natural sunlight. SAD affects 4 to 6 percent of Americans and is more common the farther north you live.
• Bipolar disorder. This condition involves moods that cycle between depression and extreme excitability, called mania. Bipolar disorder affects about 2.6 percent of American adults.
• Psychotic depression. This type of depression is the most severe form and includes breaks with reality, such as hallucinations or delusions. It is less common than other forms of depression; according to one study, psychotic depression occurs in about 5 percent of people who suffer from major depression.

The Prevalence of Depression in Combination With Other Conditions

Many conditions may coexist with depression. Depression may increase the risk for another illness, and dealing with an illness may lead to depression. “Depression is anger turned inward toward the self,” explains Lieberman. “This anger is self-destructive and therefore harmful to the body.” In fact, according to the NIMH, depression affects:

• More than 40 percent of those with post-traumatic stress disorder
• 25 percent of those who have cancer
• 27 percent of those with substance abuse problems
• 50 percent of those with Parkinson’s disease
• 50 to 75 percent of those who have an eating disorder
• 33 percent of those who’ve had a heart attack

Depression, Marriage, and Divorce

Many studies have found that being divorced, separated, or widowed is closely linked to depression. The loss of a marriage may lead to depression, or depression may lead to loss of a marriage. A 2000/2001 study published in the journalDepression and Anxiety that analyzed depression statistics from the Canadian National Population Health Survey found that major depression doubled a person’s chance of becoming divorced or separated.

The NIMH also notes that:

• Married women are more likely to be depressed than unmarried women.
• Married men are less likely to be depressed than unmarried men.
• Unhappily married women are three times more likely to be depressed than unhappily married men.

In other words, marriage seems to create a protective buffer against depression for men, but not for women.

Prevalence of Depression by Race and Age

Race seems to make a difference in the prevalence of depression, but the difference depends on the statistics you look at. According to the NIMH, African-Americans have a lower lifetime risk of depression than whites. But according to a 2010 study by the CDC, African-Americans have the highest rate of current depression (12.8 percent), followed by Hispanics (11.4 percent), and whites (7.9 percent).

The average age for a person to be diagnosed with depression is 32. Those diagnosed between the ages of 18 and 24, when there’s a 10.9 percent rate of depression, are at the greatest risk for self-harm. The depression rate drops to 6.8 percent among those age 65 and older, however, suicide rates in elderly men are higher than other age groups, perhaps due to untreated depression and other illnesses.

Americans With Depression: How Does Your State Fare?

According to the CDC, where you live has an effect on your risk of depression. This may reflect other influences on depression, such as access to health care in the area, the population’s education level, and opportunity for employment. Among the states surveyed by the CDC in 2010, those with the highest levels of depression are Alabama, Mississippi, and West Virginia. By contrast, North Dakota, Minnesota, Alaska, and Iowa have the lowest depression rates. The prevalence of depression ranges from 4.8 percent in North Dakota to 14.8 percent in Mississippi.

Depression and Suicide

Depression is involved in more than two-thirds of the 30,000 suicides that occur in the United States every year. For every two homicides, there are three suicides. “Elderly men may feel especially hopeless when their bodies break down with illness because it can destroy their sense of masculinity,” says Lieberman. That may be why the highest suicide rate among Americans is in white men who are 85 or older, many of whom may have a depressive illness.

So what do all these depression statistics tell us about Americans with depression? Perhaps the key take-away is that depression is a powerful condition affecting many. If you have symptoms of depression, you are not alone and help is available. The earlier you start treatment, the more likely you are to get a handle on the condition. The best defense against depression may very well be knowledge and awareness.

Prevalence of Bipolar Disorder

The term lifetime prevalence (LTP) describes the number of people within a population who are expected to develop a particular disorder at some time in their lives. The number is generally expressed as a percentage of “at risk” people within the context of a larger population. If there are 1000 people in the total population, and 100 of them get a particular illness at some point during their lifetimes, then the LTP for that illness is 10%, as 10% of the people within the population came down with that illness at some point in their lives.

For bipolar disorder, the LTP varies between 0.4% and 1.6% in diverse community studies [DSM-IV]. This means that in the United States, about 2 million adults (roughly 1% of the adult population) suffer from some form of bipolar disorder. According to several studies, a significant proportion of the approximately 3.4 million children and adolescents with depression in the United States may actually be experiencing the early onset of adolescent bipolar disorder, but have not yet experienced the manic phase of the illness. It is suspected that a significant number of children diagnosed in the United States with attention-deficit disorder with hyperactivity (ADHD) actually have early-onset bipolar disorder instead of or along side of ADHD. For example, an elementary school age child who seems difficult to settle in a classroom and cannot concentrate or refuses to do so might actually be showing the first adolsecent bipolar disorder signs.

Course of Bipolar Disorder

Bipolar disorder typically develops in late adolescence or early adulthood. The average age of onset is 20 for both men and women. However there is some variability in the age of onset that needs to be recognized. Some people have their first bipolar disorder symptoms during childhood, and some develop them later in life. The symptoms are often not recognized as a bipolar mood disorder right away. People may suffer for years before the condition is properly diagnosed and treated.

Bipolar disorder is a recurrent condition. More than 90% of individuals who have a single manic episode go on to have future episodes. About 60-70% of manic or hypomanic episodes occur before or after a major depressive episode. The frequency of swings during a lifetime is typically increased in those suffering from Bipolar II Disorder compared to other bipolar conditions. Approximately, 5-15% of these patients become rapid-cyclers with a poorer prognosis.

Once bipolar disorder signs have established themselves, episodes of mania and depression characteristically recur across the life span. Bipolar disorders have no cure and are chronic conditions. The risk of suicide is high among those with manic-depressive illness; approximately 10-15% of people with a bipolar diagnosis complete suicide while many more attempt suicide unsuccessfully. Bipolar patients are also at heightened risk for engaging in impulsive and risky acts other than suicide such as violent outbursts, domestic abuse, substance abuse, etc.

Fortunately, the worst (e.g., most dangerous) symptoms can be controlled and stabilized in most cases provided that proper bipolar disorder medications are prescribed and complied with. Approximately 20-30% of individuals with Bipolar I Disorder and 15% of individuals with Bipolar II Disorder will continue to display mood lability, interpersonal and occupational challenges despite bipolar disorder treatment compliance. Ongoing prophylactic (protective) treatment is generally recommended for patients even when they have not shown evidence of mood swings for extended periods of time so as to prevent the possible recurrence of suicide and other risky impulsive self-destructive behaviors.

Bipolar Disorder versus Unipolar Depression

Unipolar depression (or Major Deperssion, or Major Depressive Disorderis like bipolar depression without the mania. It consists purely of major depression’s depressive episodes without mixed or manic episodes to break things up. In contrast to bipolar mood cycling, a person with major depression does not swing out of the low energy depressive state but rather remains there until the disorder has run its course. Unipolar depression may strike one time, or it may reoccur repeatedly as a series of episodes.

Although there is some debate about whether unipolar depression is a form of bipolar disorder, the evidence currently seems to support the idea that there are two distinct but related mental illnesses at work. Firstly, unipolar depression (lifetime prevalence being approximately 5%) occurs more commonly than bipolar disorder (lifetime prevalence of approximately 1%). Also, more women are affected by unipolar depression than by bipolar disorder. Furthermore, bipolar disorder has an onset at a younger age on average, and shorter intervals between episodes once it is established, thus producing more episodes during a lifetime. In addition, treatment for unipolar depression differs from that of bipolar disorders. Unipolar depression can be treated with antidepressants alone, whereas bipolar disorder treatment requires the use of mood stabilizing drugs (which are different than antidepressant drugs). Antidepressant drugs are used to treat bipolar disorder, but generally in conjunction with mood stabilizers and not alone.

Bipolar Disorder versus Premenstrual Dysphoric Disorder

Another disorder that can be confused with bipolar disorder symptoms is Premenstrual Dysphoric Disorder (PMDD), which in the past was known as Late Luteal Phase Dysphoric Disorder. PMDD is a female-only mental health disorder characterized by serious premenstrual distress, and associated deterioration of social and emotional functioning. Women with PMDD experience a labile (changeable)mood disorder which may manifest in the form of anxiety, depression, irritability or anger, beginning approximately one week before menstruation. The difference between PMDD and regular old premenstrual symptoms (e.g., PMS) is largely a matter of severity rather than kind. PMDD symptoms are severe enough that they interfere with occupational and social functioning. For example, women who routinely must take a few days off from school or work before they get their period may have PMDD. Typically, symptoms subside a few days after the onset of menses.

Although PMDD and bipolar disorder are both associated with labile and rather extreme mood states, the two problems can be differentiated based on the rather tight synchronization of PMDD mood swings with the menstrual cycle. In contrast, the mood swings associated with bipolar disorder are not tightly linked to any regular body cycle.

Because physiological (body) illnesses, substance abuse, and other mental disorders can mimic bipolar mood symptoms, it is important that any clinician attempting to diagnose bipolar affective disorder be careful to rule out alternative causes for observed symptoms. A definitive diagnosis of bipolar disorder can only be made after a patient has been medically screened and cleared for other medical conditions which might contradict bipolar disorder diagnosis, has been sober for a long enough time for any suspected substances that might influence mood to have cleared the body, and is known not to have other mental disorders which would contradict bipolar disorder. This process takes some time to complete. Though a provisional diagnosis may be made rather quickly, so as to facilitate rapid treatment, it is common for doctors to hold off making a final and definitive bipolar disorder diagnosis until they have had time to observe a patient over a period of several months, and conduct a review of any past hospitalizations and treatments which may have occurred