A Primer on Depression and Anxiety
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Depression, also known as major depressive disorder or clinical depression, is a leading cause of disability worldwide and is a major contributor to the overall global burden of disease.


Globally, more than 264 million people of all ages suffer from depression according to the World Health Organization. With about 6.7 percent of all US adults having at least one depressive episode each year, employees suffering from depression cost employers more than $44 billion per year in lost productivity, with more than 81 percent of that lost productivity coming in the form of presenteeism.

    Depression is one of the most common mental health disorders in the US. Research suggests it is caused by a combination of genetic, biological, environmental and psychological factors. This difficult condition does not discriminate. It can begin anytime, in any race or gender, and at any income level.

    Each type can range in severity and involve a variety of different symptoms. According to the Centers for Disease Control and Prevention, about 80% of adults with depression reported at least some difficulty with work, home, or social activities because of their depression symptoms. Barriers to treatment include income, access to mental health care, poor assessments, social stigma, and misdiagnosis.

    People who have gone through adverse life events (unemployment, bereavement, psychological trauma) are more likely to develop depression. Depression can, in turn, lead to more stress and dysfunction and worsen the affected person’s life situation and depression itself.

    There are interrelationships between depression and physical health. For example, cardiovascular disease can lead to depression and vice versa. It's also not uncommon for someone with an anxiety disorder to also suffer from depression or vice versa. Nearly one-half of those diagnosed with depression are also diagnosed with an anxiety disorder.


  • 1 in 5 of those suffering from depression will also have a substance abuse issue, often because of it.
  • More than 8 million adults provide unpaid care to family members who suffer from a mental illness, spending an average of 32 hours a week providing care.
  • Mental illness is connected directly to suicide, substance abuse, family conflict, divorce, and domestic violence. There’s one suicide every 12 minutes in the US and 90% of suicides are traced to mental illness, and mainly depression.
  • Almost 75% of people with mental disorders remain untreated in developing countries with almost 1 million people taking their lives each year.


The National Institute of Health has noted that approximately 80% of patients who seek treatment for major depression show improvement within four to six weeks, from “beginning medication, psychotherapy, attending support groups or a combination of these treatments.