Most common mental illnesses in the United States

Jessica Bliss | The Tennessean

Nearly 1 in five U.S. adults lives with a mental illness. That translated to 44.7 million people in 2016. But estimates suggest that only half of the people with mental illnesses receive treatment, according to the National Institute of Mental Health.

The term mental illness refers to a wide range of mental health conditions, including depression, anxiety disorders, schizophrenia, eating disorders and addictive behaviors.

Many people may experience mental health concerns from time to time.

Government Study: Nearly One Fifth Of Americans Deal With Mental Illness Or Substance Abuse A U.S. Government study says nearly 1 in 5 American adults deals with a mental illness or substance abuse problem each year. Oregon has the highest rate, and New Jersey the lowest, according to 2012-2014 data analyzed by the U.S. Substance Abuse and Mental Health Services Administration. Overall, almost 44 million Americans 18 or older had a diagnosable mental, behavioral or emotional disorder in the past year, researchers said. They reviewed national surveys on drug use and health. SAMHSA acting deputy assistant secretary Kana Enomoto said, "The figures in SAMHSA's report remind us how important it is to take mental health as seriously as any other health condition."

Mental illness arises when ongoing signs and symptoms cause frequent stress and affect a person's ability to function, according to MayoClinic.com. Generally, mental illnesses are disorders that impact mood, thinking and behavior.

Here are some of the most common mental illnesses, as cited by the National Institute of Mental Health.

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Most common mental illnesses

1. Anxiety: An estimated 19.1 percent of U.S. adults had an anxiety disorder in the past year. Anxiety can include panic and phobias that can interfere with job performance, school work and relationships.

2. Depression: An estimated 16.2 million adults in the United States had at least one major depressive episode, lasting two weeks or longer, in 2016. This number represented 6.7 percent of all U.S. adults.

3. Bipolar disorder: At some time in their lives, an estimated 4.4 percent of U.S. adults experience bipolar disorder, which is characterized by dramatic shifts in mood, energy and activity levels that affect a person’s ability to carry out day-to-day tasks.

4. Post-traumatic stress disorder: An estimated 3.6 percent of U.S. adults had PTSD in the past year. Events that may lead to PTSD include violent personal assaults, disasters, accidents and combat. PTSD may cause persistent, frightening thoughts and memories, sleep problems and a feeling of detachment.

5. Schizophrenia: Surveys, clinical diagnostic interviews and medical records estimate the prevalence of schizophrenia in the United States as between 0.25 and 0.64 percent. Schizophrenia is characterized by disruptions in thought processes, perceptions, emotional responsiveness and social interactions.