Despite having a much higher risk of HIV than the general population, people with severe mental illness are tested for the virus at only a slightly higher rate. This represents a potential missed opportunity to identify people living with HIV and get them on treatment that can improve their health and vastly lower their risk of transmitting the virus to others.

Publishing their findings in Psychiatric Services, researchers conducted a retrospective cohort study of the records of 56,895 people enrolled in the California Medicaid program who were on one or more antipsychotic medications.Their analysis covered October 2010 through September 2011. The participants ranged in age between 18 and 67; 42 percent were older than 48.

During the one-year study period, 6.7 percent of the cohort received HIV testing. By comparison, 5.2 percent of Californians reported receiving HIV testing in 2011.

Previous research has concluded that people with severe mental illness in the United States have an HIV prevalence rate of 1.8 to 6 percent. The general population has a prevalence rate of about 0.4 percent.

The authors in the new paper found that men in the study were 32 percent less likely to be tested for HIV than women. Compared with whites, Asian and Pacific Islanders were 53 percent less likely and Blacks were 82 percent more likely to be tested. Those who had substance abuse disorders were more likely to be tested than those who did not have such disorders. The strongest predictor of getting an HIV test was receiving nonpsychiatric medical care.

“Public health administrators must prioritize HIV testing for early identification of HIV infection and prevention of HIV transmission,” the study authors concluded.

To read a press release about the study, click here.

To read the study abstract, click here.