Nearly 50% of adults experience a mental illness at some point in their lives. More than half of these people experience moderate to severe symptoms. In fact, 4 of the 10 leading causes of disability among people aged 5 and older are mental health disorders, with depression being the number one cause of all illnesses that cause disability. Despite this high prevalence of mental illness, only about 20% of people who have a mental illness receive professional help.
Although tremendous advances have been made in the understanding and treatment of mental illnesses, the stigma surrounding them persists. For example, people with mental illness may be blamed for their illness or viewed as lazy or irresponsible. Mental illness may be seen as less real or less legitimate than physical illness, leading to reluctance on the part of policy makers and insurance companies to pay for treatment. However, the growing realization of how much mental illness affects health care costs and the number of lost work days is changing this trend.
Currently, mental illness is thought to be caused by a complex interaction of hereditary and environmental factors. Research has shown that for many mental health disorders, hereditary plays a part. Often, a mental health disorder occurs when people whose genetic make-up makes them vulnerable to such disorders experience extra stress in their family or social life or at work. Also, many experts think that malfunction of chemical messengers in the brain (neurotransmitters) may contribute to mental health disorders. Brain imaging techniques, such as magnetic resonance imaging (MRI) and positron emission tomography (PET), show changes in the brain in people with a mental health disorder. Thus, many mental health disorders appear to have a biologic component, much like disorders that are considered neurologic (such as Alzheimer disease). However, whether the changes seen on imaging tests are the cause or result of the mental health disorder is unclear.
Mental illness cannot always be clearly differentiated from normal behavior. For example, distinguishing normal bereavement from depression may be difficult in people who have had a significant loss, such as the death of a spouse or child. Likewise, a diagnosis of anxiety disorder in people who are worried and stressed about work is somewhat arbitrary because most people experience these feelings at some time. The line between having certain personality traits and having a personality disorder can be blurry. Thus, mental illness and mental health are best thought of as a continuum. Any dividing line is usually based on how long symptoms last, how much people change from their usual self, and how severely symptoms affect their life. Therefore, when thinking about mental illness, people should distinguish long-lasting (chronic) serious mental illness that severely limits a person's daily activities or ability to work (such as an ongoing, lifelong psychosis) from brief but serious episodes of symptoms that are expected to resolve and from chronic symptoms that do not interfere with activities or work.
In recent decades, there has been a movement to bring mentally ill people out of institutions (deinstitutionalization) and support them so that they can live in communities. This movement was made possible by the development of effective drugs, along with some change in attitude about the mentally ill. With this movement, greater emphasis has been placed on viewing mentally ill people as members of families and communities. A decision by the U.S. Supreme Court in 1999 significantly aided this change. This decision, called the Olmstead decision, requires states to provide mental health treatment in community settings whenever such placement is medically appropriate.
Research has shown that certain interactions between a person with mental illness and family members can improve or worsen mental illness. Therefore, family therapy techniques that prevent the chronically mentally ill from needing to be reinstitutionalized have been developed. Today, the family of a mentally ill person is more involved than ever as an ally in treatment. The family doctor also plays an important role in rehabilitating a mentally ill person into the community. In addition, mentally ill people who must be hospitalized are less likely to be isolated and restrained than in the past, and they are often discharged early into day treatment centers. These settings are less expensive because fewer staff members are needed, the emphasis is on group therapy rather than individual therapy, and people sleep at home or in halfway houses.
However, the deinstitutionalization movement has had its share of problems. Because laws now prevent mentally ill people who are not a danger to themselves or society from being institutionalized or treated against their will, many of these people have become homeless or ended up in the prison system. Many die young because of exposure or infection. Although these laws protect people's civil rights, they make it more difficult to provide needed treatment to many mentally ill people, some of whom may be extremely irrational when untreated. Homelessness also has an effect on society. Because of the problems related to deinstitutionalization, novel approaches to treatment, such as assertive community treatment (ACT), have been developed. They help provide a safety net for people with chronic serious mental illness. ACT uses a team of social workers, rehabilitation specialists, counselors, nurses, and psychiatrists (a multidisciplinary team). The team provides individualized services to people who have a serious mental illness and who cannot or will not go to a doctor's office or to a clinic for help. The services are provided in the person's own home or neighborhood—for example, in nearby restaurants, parks, or stores.
Everyone requires a social network to satisfy the human need to be cared for, accepted, and emotionally supported, particularly in times of stress. Research has shown that strong social support may significantly improve recovery from both physical and mental illnesses. Changes in society have diminished the traditional support once offered by neighbors and families. As an alternative, self-help groups and mutual aid groups have sprung up throughout the country.
Some self-help groups, such as Alcoholics Anonymous and Narcotics Anonymous, focus on addictive behavior. Others act as advocates for certain segments of the population, such as the handicapped and older people. Still others, such as the National Alliance for the Mentally Ill, provide support for family members of people who have a severe mental illness.
Last full review/revision December 2012 by Caroline Carney Doebbeling, MD, MSc