Understanding associations between serious mental illness and HIV among patients in the VA Health System.

OBJECTIVE: This study compared the recorded prevalence of HIV among veterans with and without serious mental illness.
METHODS: This cross-sectional study examined data from a national sample of veterans who received a diagnosis of serious mental illness (schizophrenia, bipolar disorder, and other, nonorganic psychoses) in fiscal year 2002 (FY2002) (N=191,625) and from a national random sample of veterans in FY2002 who did not receive serious mental illness diagnoses (N=67,965). Logistic regression was used to evaluate the recorded prevalence and predictors of HIV.
RESULTS: HIV diagnoses were recorded for 1.0% of patients with serious mental illness and .5% of patients without serious mental illness. Multivariate analyses indicated that individuals with bipolar disorder were no more likely than those without serious mental illness to have a recorded HIV diagnosis (OR=1.08, CI=.93-1.24), whereas those with other psychoses were more likely to have one (OR=1.18, CI=1.01-1.38). An interaction was observed between schizophrenia and substance use disorder. Compared with patients who had neither schizophrenia nor a substance use disorder, those with schizophrenia without a substance use disorder were less likely to have a recorded HIV diagnosis (OR=.49, CI=.42-.58), whereas those with a substance use disorder were more likely to have a recorded HIV diagnosis (OR=1.22, CI=1.04-1.43).
CONCLUSIONS: Despite the elevated crude recorded prevalence of HIV, multivariate analyses suggested that HIV-related risk factors underlie the associations between HIV and the serious mental illness diagnoses. For patients with schizophrenia, this study is the first to demonstrate reduced HIV risk in the absence of a substance use disorder.