Lack of housing serves as a social determinant of mental health. Being afflicted with a mental disorder, including substance use disorders, where mental health services are unavailable or difficult to access can also drive homelessness for the same reasons as disabilities. A United States federal survey in 2005 indicated that at least one-third of homeless men and women had serious psychiatric disorders or problems. Autism spectrum disorders and schizophrenia are the top two common mental disabilities among the U.S. homeless. Personality disorders are also very prevalent, especially Cluster A.E. Fuller Torey (2008): The Insanity Offense – How America's Failure to Treat the Seriously Mentally Ill Endangers Its Citizens, Substance abuse can also cause homelessness from behavioral patterns associated with addiction, that alienate an addicted individual's family and friends, who could otherwise provide support during difficult economic times.
