Dec 05, 2014 10:57 AM EST By J Baulkman, UniversityHerald Reporter

People battling mental illness are more likely to have been tested for HIV than those without mental illness, according to a recent study.

Researchers from the University of Pennsylvania School of Medicine and the U.S. Centers for Disease Control and Prevention (CDC) found that the most seriously ill -- those with schizophrenia and bipolar disease -- had the highest rate of HIV testing.

"Our finding that persons with mental illness were tested for HIV at a higher rate than those without mental illness is encouraging and consistent with previous analyses," Baligh R. Yehia, lead author of the study and an assistant professor of Medicine at the Perelman School of Medicine at the University of Pennsylvania, said in a statement. "However, the large number of people with mental illness who still have not been tested necessitates increased public health prevention efforts, particularly in light of the increased HIV risk in this population."

For the study, researchers collected and analyzed data from nearly 22,000 adult respondents from the 2007 National Health Interview Survey (NHIS).

They found that 15 percent of respondents reported a psychiatric disorder. Of these, 89 percent had symptoms of depression and/or anxiety, 8.5 percent had bipolar disorder, and 2.6 percent had schizophrenia spectrum disorder. Among persons reporting at least one mental illness, 48.5 percent had been tested for HIV. The 48.5 percent rate compares to a testing rate of 35 percent among those without mental illness. More specifically, 64 percent of persons with schizophrenia, 63 percent of persons with bipolar disorder, and 47 percent of persons with depression and/or anxiety reported ever being tested for HIV.

Separate research has found that mentally ill individuals are more likely than others to engage in high-risk behaviors associated with HIV transmission, including unprotected sexual intercourse, injection drug use, and sex with multiple partners.

The findings are detailed in the journal AIDS Patient Care and STDs.

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