Black patients were more than twice as likely to be diagnosed with schizophrenia as non-Latino white patients, according to new data.
“In the United States, African American individuals in clinical venues are disproportionately diagnosed with schizophrenia compared with white individuals,” the researchers wrote.
Michael A. Gara, PhD, and colleagues gathered data on patients aged 16 to 45 years who self-identified as black (n=241), non-Latino white (n=220) and Latino (n=149). Patients were included in the study if they exhibited significant affective symptoms.
Gara and colleagues collected patients’ medical records from six US clinical settings. At each site, trained clinical interviewers completed the Diagnostic Interview for Genetic Studies and additional questionnaires for each patient. The medical records and interview transcripts were sent to the University of Cincinnati, where editors deleted all references to people, names, places and linguistic idiosyncrasies, phrasing or syntax that might signal to ethnicity. The redacted material was then distributed to two independent diagnostic experts — masked to the study — who rated patients’ symptoms and diagnoses through consensus.
The researchers used logistic regression models to determine whether higher rates of schizophrenia in blacks would continue after controlling for a number of confounding variables, including blinded expert diagnoses of serious affective illness.
Results show that black patients were significantly more likely to be diagnosed with schizophrenia than non-Latino white patients (OR=2.7; 95% CI, 1.5-5.1). Similar differences in diagnoses between black patients and white patients occurred when schizophrenia was “more broadly defined,” according to researchers (OR=2.5; 95% CI, 1.4-4.5). The effect did not extend to Latino patients. Black patients did not differ significantly from white patients in overall severity of manic and depressive symptoms, but black patients exhibited more severe psychosis.
The researchers concluded that psychotic symptoms in black patients may be overvalued by clinicians, skewing diagnoses toward the schizophrenia-spectrum, even if the severity of black patients’ symptoms is the same as that of white patients.
“The results strongly support the need for a national approach to enhance quality of mental health care by eliminating disparities in psychiatric diagnoses that occur systematically in this vulnerable population,” the researchers wrote. “Moreover, these results remind clinicians to consistently challenge their own diagnostic assessments, particularly in patients from other ethnic groups or in those who are failing to respond to treatment.”
Disclosure: Refer to the study for a complete list of financial disclosures.