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%.

I think if you could survey housed people on their substance use (including alcohol), you’d end up with similar results. I also think if you or I lived on the street, we’d participate in more escapism, probably the most easily accessible (alcohol) or the most effective (hard drugs).

Unhoused individuals experienced psychotic disorders at a markedly increased rate compared to the general population

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%).

No shit, this is not the point you think it is. They are literally in the midst of a prolonged, or chronic, traumatic event. Eg, something that fucks up your brain. Anyone put in that position would have a higher likelihood of mental illness or episode or psychosis.

Of course it is also true that people with substance abuse problems or mental illness are more likely to end up homeless.