Homelessness and Mental Illness: A Challenge to Our Society

Posted: November 19, 2018
Homelessness and Mental Illness: A Challenge to Our Society

What is the prevalence of mental illness among people experiencing homelessness in the U.S.?

According to a 2015 assessment by the U.S. Department of Housing and Urban Development, 564,708 people were homeless on a given night in the United States. At a minimum, 140,000 or 25 percent of these people were seriously mentally ill, and 250,000 or 45 percent had any mental illness. By comparison, a 2016 study found that 4.2 percent of U.S. adults have been diagnosed with a serious mental illness.

What are the most common types of mental illness among people experiencing homelessness?

Affective disorders such as depression and bipolar disorder, schizophrenia, anxiety disorders and substance abuse disorders are among the most common types of mental illness in the homeless population.

How are homelessness and mental illness connected?

Most researchers agree that the connection between homelessness and mental illness is a complicated, two-way relationship. An individual’s mental illness may lead to cognitive and behavioral problems that make it difficult to earn a stable income or to carry out daily activities in ways that encourage stable housing. Several studies have shown, however, that individuals with mental illnesses often find themselves homeless primarily as the result of poverty and a lack of low-income housing. The combination of mental illness and homelessness also can lead to other factors such as increased levels of alcohol and drug abuse and violent victimization that reinforce the connection between health and homelessness.

Can homelessness exacerbate an existing mental illness?

Studies do show that homelessness can be a traumatic event that influences a person’s symptoms of mental illness. Having ever been homeless and the time spent homeless can be related to higher levels of psychiatric distress, higher levels of alcohol use and lower levels of perceived recovery in people with previous mental illness.

How do homelessness and mental illness influence a person's interactions with police and the justice system?

In general, homelessness among people with mental illness can lead to more encounters with police and the courts. For instance, rates of contact with the criminal justice system and victimization among homeless adults with severe symptoms such as psychosis, are higher than among housed adults with severe mental illness. Homeless adults with mental illness who experienced abuse or neglect in childhood are more likely to be arrested for a crime or be the victim of crime.

How does homelessness affect mental illness within families?

One of the biggest impacts of homelessness on mental illness comes through its effect on the mothers of families. For instance, mothers who experience postpartum depression during the first year after birth are at higher risk for homelessness or factors leading to homelessness such as evictions or frequent moves in the two to three years after the postpartum year. One of the largest studies of children and homelessness (17,000 children in Denmark) found a higher incidence of psychiatric disorders, including substance abuse, among adolescents with a mother or both parents with a history of homelessness.

What kinds of interventions help people with mental illness experiencing homelessness?

Programs that provide long-term (a year or longer) stable housing for people with mental illnesses can help to improve mental health outcomes, including reducing the number of visits to inpatient psychiatric hospitals. A 2015 study concluded that services that deliver cognitive and social skill training, particularly in developing and maintaining relationships, would be useful in helping people with mental illnesses and homelessness regain housing.

Written By Peter Tarr, Ph.D.

Click here to read the Brain & Behavior Magazine's September 2018 issue



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