April 30, 2013

Over-diagnosis and over-treatment of depression is common in the U.S.

Americans are over-diagnosed and over-treated for depression, according to a new study conducted at the Johns Hopkins Bloomberg School of Public Health. The study examines adults with clinician-identified depression and individuals who experienced major depressive episodes within a 12-month period. It found that when assessed for major depressive episodes using a structured interview, only 38.4 percent of adults with clinician-identified depression met the 12-month criteria for depression, despite the majority of participants being prescribed and using psychiatric medications. The results are featured in the April 2013 issue of Psychotherapy and Psychosomatics.

“Depression over-diagnosis and over-treatment is common in the U.S. and frankly the numbers are staggering,” said Ramin J. Mojtabai, PhD, author of the study and an associate professor with the Bloomberg School’s Department of Mental Health. “Among study participants who were 65 years old or older with clinician-identified depression, 6 out of every 7 did not meet the 12-month major-depressive-episodes criteria. While participants who did not meet the criteria used significantly fewer services and treatment contacts, the majority of both groups used prescription psychiatric medication.”

Using a sample of 5,639 participants from the 2009-2010 United States National Survey of Drug Use and Health, Mojtabai assessed clinician-identified depression based on questions about conditions that the participants were told they had by a doctor or other medical professional in the past 12 months. The study indicates that even among participants without a lifetime history of major or minor depression, a majority reported having taken prescription psychiatric medications.

“A number of factors likely contribute to the high false-positive rate of depression diagnosis in community settings, including the relatively low prevalence of depression in these settings, clinicians’ uncertainty about the diagnostic criteria and the ambiguity regarding sub-threshold syndromes,” said Mojtabai. “Previous evidence has highlighted the under-diagnosis and under-treatment of major depression in community settings. The new data suggest that the under-diagnosis and under-treatment of many who are in need of treatment occurs in conjunction with the over-diagnosis and over-treatment of others who do not need such treatment. There is a need for improved targeting of diagnosis and treatment of depression and other mental disorders in these settings.”

“Clinician-Identified Depression in Community Settings: Concordance with Structured-Interview Diagnoses,” was written by Ramin J. Mojtabai.

Media contact for Johns Hopkins Bloomberg School of Public Health: Natalie Wood-Wright at 410-614-6029 or nwoodwri@jhsph.edu.