New University of Michigan research indicates black men are over-diagnosed with schizophrenia at least five times higher than any other group, a trend that dates back to the 1960s.

Jonathan Metzl, an associate professor of psychiatry and women’s studies, examined archives of Ionia State Hospital for the Criminally Insane and learned that black men, mainly from Detroit during the civil rights era, were taken there and often misdiagnosed with schizophrenia.

“Some patients became schizophrenic because of changes in their diagnosis rather than their clinical symptoms,” Metzl, a 2008 Guggenheim award recipient, said in a press release.

Events at Ionia mirrored national conversations that linked the disease with blackness, madness and civil rights, Metzl said.

How the psychiatric profession defined schizophrenia also changed during that period. From the 1920s to 1940s, doctors considered the illness as affecting non-violent white individuals - mainly women - but later changed the language to violent, hostile, angry and aggressive as a way to label black men, Metzl said in the release.

“It’s an easy thing to say this was racism, but it’s a much more complicated story … that’s still playing out in present day,” said Metzl, director of U-M’s Culture, Health and Medicine Program.

Despite increased efforts for cultural competency training, over-diagnosis of schizophrenia in black men has remained, the release said.

Metzl’s findings appear in the new book, “The Protest Psychosis How Schizophrenia Became a Black Disease.”