Depression Facts: The Leading Cause of Disability WorldwideOver 350 million people of all ages suffer from depression worldwide.  Depression is the leading cause of disability worldwide, and is a major contributor to the global burden of disease.  Major depression is the leading cause of disability in the U.S. for ages 15 to 44.  Depression affects around 18.1 million American adults, or about 10 percent of the U.S. population age 18 or older in a given year. This combines major and minor depression.  The median age of onset for depression is between 31 and 32.  Over $22 billion was spent on depression treatment in 2009. The number is even higher today. 
Studies show that depression is very common around the world. Over 18 percent of people in the United States and Europe, and over 9 percent of people in developing countries experience significant depression at some point in their lives. And the number of people facing depression is rising. The number of people in the United States at any given time who reported having major depression more than doubled from 1992 to 2002 (3 to 7 percent). This is one of many sobering depression facts.
Moreover, a high percentage of people suffering from depression stay quiet and never report it. This is true in both adults and teenagers. Depression among adolescents, which typically presents in primary care, is under-diagnosed and under-treated. As a result, approximately 70 percent of depressed teenagers do not receive treatment.  Given the potential life-threatening implications of under-diagnosed and under-treated adolescent depression, primary care providers and child psychiatrists must work together to adequately identify and treat depression in teens. Early screening is essential in every primary care setting. The more depression facts you know, the more you can help others.
Depression Facts: Gender Aspects of Depression
Question: Does depression affect more men or women?
Answer: More than twice as many women seek treatment for depression as men.
In the United States, the proportion of women who have depression is approximately two times greater than that of men. A nationally representative study of adults living in the community found that the 12 month prevalence of major depression in females was 7 percent as compared to males at 4 percent. The rate of women experiencing depression over their lifetime is 17 percent, compared to 9 percent for men.  A survey of 72,933 community-dwelling adults from 15 countries found the lifetime prevalence of major depression and dysthymia were each 1.9 times higher in females compared with men. 
Depression Facts; Age Considerations of Depression
Question: Do younger or older people experience more depression?
Answer: Younger adults report depression more often than older adults.
Depression is not a normal consequence of aging. In fact, rates of depression decline as people get older. Major depression is more commonly reported in younger than older adults in the community. A survey of over 9,000 adults in the United States found that the lifetime prevalence of major depression in people 65 years or older was significantly less compared to younger age groups.  Studies reveal that rates of major depression for home-dwelling older adults are approximately two percent, and for minor depression the rate is closer to 10 percent. 
Depression Facts: Health Aspects of Depression
Question: Do adults with medical illness experience higher rates of depression?
Answer: Yes, illness is a significant risk factor for depression, especially in adults over the age of 65.
Residents of assisted living or skilled nursing facilities, recipients of home health care, and patients suffering from a wide range of acute and chronic medical conditions have higher rates of depression compared with older adults in general. Hospitalized geriatric populations have prevalence rates of depression over 30 percent, and seniors with myocardial infarction (MI), cancer, or stroke have rates over 40 percent. It’s important for people to know as many depression facts as possible.
Last updated 10/01/14
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