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Up To 51% Of Schizophrenia Cases Misdiagnosed Before Reaching Specialty Clinic

Jon Olav Eikenes

About half the people referred to the clinic with a schizophrenia diagnosis didn’t actually have schizophrenia, Johns Hopkins Medicine researchers report in a small study.

Therapies can vary widely for people with schizophrenia, bipolar disorder, major depression or other serious types of mental illness, and a misdiagnosis can lead to inappropriate or delayed treatment.

The findings, the researchers say, suggest that second opinions at a specialized schizophrenia clinic after initial diagnosis are wise efforts to reduce the risk of misdiagnosis, and ensure prompt and appropriate patient treatment.

A Fad Diagnosis?

Schizophrenia is a chronic, severe and disabling disorder marked by disordered thinking, feelings and behavior. People who reported hearing voices or having anxiety were the ones more likely to be misdiagnosed.

“Because we’ve shined a spotlight in recent years on emerging and early signs of psychosis, diagnosis of schizophrenia is like a new fad, and it’s a problem especially for those who are not schizophrenia specialists because symptoms can be complex and misleading. Diagnostic errors can be devastating for people, particularly the wrong diagnosis of a mental disorder,”

said Krista Baker, L.C.P.C., manager of adult outpatient schizophrenia services at Johns Hopkins Medicine.

According to the National Institute of Mental Health, schizophrenia affects an estimated 0.5 percent of the world population, and is more common in men. It typically arises in the late teens, 20s and even as late as the early 30s in women.

Symptoms such as disordered thinking, hallucinations, delusions, reduced emotions and unusual behaviors can be disabling, and drug treatments often create difficult side effects.

Small Study Sample

The new study was prompted in part by anecdotal evidence among health care providers in Baker’s specialty clinic that a fair number of people were being seen who were misdiagnosed. These patients usually had other mental illnesses, such as depression.

To see if there was rigorous evidence of such a trend, the researchers looked at patient data from 78 cases referred to EPIC, their specialty clinic at Johns Hopkins Bayview Medical Center, for consultation between February 2011 and July 2017. Patients were an average age of 19, and about 69 percent were men.

This is a small sample size, non-representative cohort. Jumping to the conclusion that this tells us something about national trends is probably a bad idea.

However, if further study confirms the findings, it would lend support to the belief by the Johns Hopkins team that overdiagnosis may be a national problem, because they see patients from across the country who travel to Johns Hopkins for an opinion. They hope to examine the experience of other specialty consultation clinics in the future.

Seventy-four percent were white, 12 percent African American and 14 percent were another ethnicity. Patients were referred to the clinic by general psychiatrists, outpatient psychiatric centers, primary care physicians, nurse practitioners, neurologists or psychologists.

Each consultation by the clinic took three to four hours, and included interviews with the patient and the family, physical exams, questionnaires, and medical and psychosocial histories.

Feeling Anxiety, Hearing Voices

Of the patients referred to the clinic, 54 people came with a predetermined diagnosis of a schizophrenia spectrum disorder. Of those, 26 received a confirmed diagnosis of a schizophrenia spectrum disorder following their consultation with the EPIC team, which is composed of licensed clinicians and psychiatrists.

Fifty-one percent of the 54 cases were rediagnosed by clinic staff as having anxiety or mood disorders. Anxiety symptoms were prominent in 14 of the misdiagnosed patients.

One of the other most common symptoms that the researchers believe may have contributed to misdiagnosis of schizophrenia was hearing voices, as almost all incorrectly diagnosed patients reported auditory hallucinations.

“Hearing voices is a symptom of many different conditions, and sometimes it is just a fleeting phenomenon with little significance. At other times when someone reports ‘hearing voices’ it may be a general statement of distress rather than the literal experience of hearing a voice. The key point is that hearing voices on its own doesn’t mean a diagnosis of schizophrenia,”

said Russell L. Margolis, M.D., professor of psychiatry and behavioral sciences and the clinical director of the Johns Hopkins Schizophrenia Center at the Johns Hopkins University School of Medicine.

Checklist Psychiatry

In speculating about other reasons why there might be so many misdiagnoses, the researchers say that it could be due to overly simplified application of criteria listed in the Diagnostic Statistical Manual of Mental Disorders, a standard guide to the diagnosis of psychiatric disorders.

“Electronic medical record systems, which often use pull-down diagnostic menus, increase the likelihood of this type of error,”

said Margolis, who refers to the problem as “checklist psychiatry.”

Another possible explanation lies in the fact that schizophrenia can be preceded by a prodromal phase also called the at-risk mental state, in which people experience lesser symptoms of psychosis. Among individuals diagnosed in the at-risk state, only about 25% eventually develop full-blown psychosis, which menas about 75% of those experiencing considerable psychotic symptoms for some period of time will not actually develop schizophrenia.

Perhaps these non-experts who came up with the initial diagnoses may have been unfamiliar with the at-risk state since it is a relatively recent concept.

Dr. Margolis did caution that the study was limited to patients evaluated in one clinic.

“The big take-home message from our study is that careful consultative services by experts are important and likely underutilized in psychiatry. Just as a primary care clinician would refer a patient with possible cancer to an oncologist or a patient with possible heart disease to a cardiologist, it’s important for general mental health practitioners to get a second opinion from a psychiatry specialty clinic like ours for patients with confusing, complicated or severe conditions. This may minimize the possibility that a symptom will be missed or overinterpreted,”

he said.

[1] Coulter, Chelsey, Baker, Krista K., Margolis, Russell L. Specialized Consultation for Suspected Recent-onset Schizophrenia Diagnostic Clarity and the Distorting Impact of Anxiety and Reported Auditory Hallucinations. Journal of Psychiatric Practice, 2019 DOI: 10.1097/PRA.0000000000000363