Summary: African American patients with major depressive disorder are disproportionately at risk of being diagnosed with schizophrenia. The Rutgers study indicates clinicians may prioritize psychotic symptoms over depressive symptoms when assessing Black patients, contributing to racial disparities in psychiatric diagnoses.

Source: Rutgers University

African American Patients with Severe Depression Are More Likely to Be Misdiagnosed with Schizophrenia

A new study from Rutgers University finds that African Americans who present with severe depressive symptoms are more often diagnosed with schizophrenia than white patients with comparable symptoms. The research, published online prior to its appearance in the February 2019 issue of Psychiatric Services, analyzed electronic medical records from a community behavioral health clinic where screening for major depression was part of the intake for patients evaluated for schizophrenia.

Researchers reviewed records for 1,657 clinic patients, including 599 Black patients and 1,058 non-Latino white patients. The clinic routinely screened new patients for major depression using the nine-item Patient Health Questionnaire (PHQ-9). The study compared rates of positive depression screens among patients ultimately diagnosed with schizophrenia or schizoaffective disorder.

Key Findings

The analysis revealed that among patients diagnosed with schizophrenia, African Americans were significantly more likely than non-Latino whites to screen positive for major depression (PHQ-9 score ≥ 15). In contrast, among patients diagnosed with schizoaffective disorder, the difference between racial groups was not statistically significant. These results suggest that clinicians may be under-recognizing mood symptoms in African American patients who are labeled with a schizophrenia diagnosis.

Michael Gara, Ph.D., a professor of psychiatry at Rutgers Robert Wood Johnson Medical School and a member of Rutgers University Behavioral Health Care, explained that schizophrenia is a diagnosis of exclusion. Clinicians should rule out mood disorders and other causes of symptoms before assigning a schizophrenia diagnosis. “There has been a tendency for clinicians to overemphasize the relevance of psychotic symptoms and overlook symptoms of major depression in African Americans compared with other racial or ethnic groups,” Gara said.

Possible Contributing Factors

The authors note that multiple factors may contribute to diagnostic disparities. These include genetic and environmental influences, socioeconomic factors such as poverty, and experiences of discrimination. Early-life conditions like infections or malnutrition may also affect symptom presentation. Additionally, the interpersonal dynamics of an assessment — including mistrust or hopelessness a patient might feel when evaluated by someone from a different racial group — could influence how symptoms are expressed and interpreted.

Importantly, the study does not claim that African Americans inherently have higher rates of depression co-occurring with schizophrenia. Rather, the pattern is consistent with prior research suggesting clinicians may place disproportionate weight on psychotic symptoms in African American patients, increasing the likelihood of schizophrenia diagnoses even when mood symptoms are present at similar levels to those seen in white patients.

Clinical and Public Health Implications

Misdiagnosis has meaningful clinical consequences. Treatments for mood disorders and schizophrenia differ substantially, and accurate diagnosis is critical to achieving the best outcomes. Patients with major depression with psychotic features or bipolar disorder who are misdiagnosed with schizophrenia may be denied appropriate mood-stabilizing or antidepressant treatments. This can worsen the underlying illness and elevate the risk of suicide. Conversely, antipsychotic medications commonly used for schizophrenia can have serious side effects, including metabolic issues such as weight gain and diabetes.

Based on their findings, the researchers recommend routine screening for major depression when evaluating Black patients for schizophrenia in community mental health settings. Implementing systematic depression screening could reduce racial disparities in diagnostic practices and help ensure patients receive the most appropriate treatment for their condition.

Study Methods

The investigators de-identified electronic medical record (EMR) data for 1,657 patients seen at Rutgers University Behavioral Health Care certified community outpatient clinics over a nine-month period beginning July 1, 2017. They used Fisher’s exact test to compare the proportion of patients who screened positive for major depression (PHQ-9 score ≥ 15) among African American and non-Latino white patients diagnosed with schizophrenia or schizoaffective disorder.

Conclusions

The study’s results align with a substantial body of literature indicating racial differences in the diagnosis of schizophrenia in the United States. These disparities appear to result in part from clinicians underemphasizing mood symptoms among African American patients. If replicated in other settings, the findings support a case for routine depression screening in community mental health clinics as a step toward reducing diagnostic disparities and improving treatment accuracy.

Source: Rutgers University
Media Contact: Patti Verbanas, Rutgers University
Original Research: “A Naturalistic Study of Racial Disparities in Diagnoses at an Outpatient Behavioral Health Clinic.” Michael A. Gara, Ph.D.; Shula Minsky, Ed.D.; Steven M. Silverstein, Ph.D.; Theresa Miskimen, M.D.; Stephen M. Strakowski, M.D. Published Online: 10 Dec 2018. DOI: 10.1176/appi.ps.201800223