We recently completed a case–control study of 100 literally homeless and 100 never homeless indigent schizophrenic men in New York City, in which concurrent substance abuse and antisocial personality disorder were widespread. In this paper we probe the correlates of ‘pure’ schizophrenia (single disorder, N = 60), schizophrenia and substance abuse (double disorder, N = 89), and schizophrenia, substance abuse, and antisocial personality disorder (triple disorder, N = 50), across the homeless/never homeless distinction. Subjects were recruited from a homeless shelter and mental health service programmes in Upper Manhattan. Psychologist and social worker interviewers administered the Structured Clinical Interview for DSM-III-R, I, and II and other structured instruments to explore social, family and illness history, the current illness, and aspects of treatment and family support. Codisorder subjects emerged from more disadvantaged family backgrounds, experienced greater school difficulties, began drug use in early adolescence, were more prone to hyperactivity in childhood, and were more likely to have spent time in jail. While codisorder groups did not differ on key aspects of schizophrenia, the triple disorder group was found to suffer from a more severe form of substance abuse than double disorder subjects, associated with an earlier age of onset and abuse of a wider array of substances.
The widespread prevalence of codisorders among indigent schizophrenic men has major significance for clinical psychiatry. Study of the correlates of codisorders has revealed important differences in social, family, and illness history which may guide the development of more effective treatments and improved service delivery.