Psychiatric Disorders and Homelessness

Homelessness can predispose individuals to psychiatric disorders. Conversely, certain psychiatric disorders can increase the risk of becoming homeless. A recent article in JAMA Psychiatry by Rebecca Barry, Dallas Seitz, and colleagues provides important information about the prevalence of specific psychiatric disorders in persons who are experiencing homelessness.

These authors performed a meta-analysis of data reported in 85 research articles. They selected these articles because they fulfilled rigorous quality criteria and included diagnoses based on the International Classification of Disease (ICD), the Diagnostic and Statistical Manual of Mental Disorders (DSM), or standardized diagnostic instruments. They excluded studies on suicide, self-harm, cognitive impairment (except dementia), neurological disorders, and smoking. They also excluded studies where the entire population was likely to have a psychiatric diagnosis; for example, studies focusing on patients in psychiatric clinics. Most studies defined “homeless” as living in shelters or in places not intended as a permanent dwelling. The final analysis examined data from 48,414 unhoused adults (18 years and older).

Current psychiatric disorders

Overall, the investigators found that two-thirds (67%) of unhoused persons were diagnosed with a current psychiatric disorder. The most common was substance use disorder. Alcohol use disorder occurred in over 25% of these individuals, and substance use disorders, including alcohol use disorder, occurred in over 43%.

Unhoused individuals experienced psychotic disorders at a markedly increased rate compared to the general population. In some studies, about 14% of those experiencing homelessness were diagnosed with a psychotic disorder. In other studies, about 7% were diagnosed with schizophrenia and 8% with bipolar disorder. Although not specifically reported in this study, many individuals with psychotic disorders also have substance use disorders.

Antisocial personality disorder, major depression, anxiety disorders, and post-traumatic stress disorder were also common in unhoused individuals, occurring in about 26%, 19%, 14%, and 10.5%, respectively.

The overall lifetime prevalence of psychiatric disorders among individuals experiencing homelessness was estimated to be 75%. It was higher for men (86%) than for women (69%).

Important trends

The authors report that there are indications that the prevalence of current mental illness in unhoused populations may be increasing. In studies conducted prior to 2010, the prevalence was 48% compared with 76% in studies reported after 2010.

Implications

The great majority of unhoused individuals have a current psychiatric disorder. Homelessness may exacerbate psychiatric disorders, and certain psychiatric disorders may increase the risk of homelessness. For strategies addressing the mental health needs of unhoused individuals to be most successful, access to both housing and mental health treatment must be considered. In addition, better access to quality mental health care may help prevent some individuals from experiencing homelessness in the first place.

This column was written by Eugene Rubin MD, PhD, and Charles Zorumski MD.