Depression is frequently overdiagnosed and overtreated in American adults, according to a national survey study.
The study explored whether patients identified as depressed by their clinicians also met the DSM-IV diagnostic criteria for 12-month major depressive episodes (MDE). Results showed that of the 5,639 participants with clinician-identified depression, only 38.4% actually met the MDE criteria. Additionally, a majority of participants reported using prescribed psychiatric medications, regardless of whether they met MDE conditions.
"This finding highlights the growing trends in prescription and use of psychiatric medications, and especially antidepressants, in the USA, even in the absence of a psychiatric diagnosis," wrote study author Dr. Ramin Mojtabai of the department of mental health at Johns Hopkins Bloomberg School of Public Health, Baltimore.
A sample of adult participants was drawn from the 2009 and 2010 National Survey of Drug Use and Health (NSDUH). Participants completed an assessment in the form of a computer-assisted in-person interview to determine whether they met DSM-IV criteria for major depressive episodes. Using questions derived from the Composite International Diagnostic Interview (CIDI) from the National Comorbidity Survey Replication, participants had to meet 5 of 9 symptom criteria and the DSM-IV clinical significance criteria (distress or impairment in functioning).
In addition to diagnostic criteria for depression, participants also were asked to report any inpatient or outpatient treatment or medications sought and prescribed over the past 12 months. Demographic information, such as education, general health, and employment status, also was collected.
Results showed that adults in the groups aged 35-49 years and 65 years and older were less likely to meet the 12-month MDE criteria than were adults aged 18-25 years.
"In contrast, participants who were out of the workforce, those who were divorced or separated, the more educated and those with poorer self-rated health were more likely to meet the 12-month MDE criteria," Dr. Mojtabai wrote.
He added that the rate of false-positive diagnosis found in this study echoes that of prior research, and that numerous factors could contribute to this high rate, such as a generally low incidence of depression in community settings, a lack of clinician knowledge about diagnostic criteria, and "ambiguity regarding subthreshold syndromes."
Dr. Mojtabai noted a few limitations to this study. First, he speculated that the true prevalence of clinician-diagnosed depression is likely much higher than is estimated in this study, as many doctors might not share their diagnostic impressions with patients. Second, he cautioned that structured interviews and clinician diagnoses are measures of "imperfect sensitivity." Third, the type of doctor was not specified in the NSDUH survey used to recruit participants. Fourth, some patients diagnosed with depression might in fact have another disorder, such as anxiety or adjustment disorder, which might benefit from antidepressant medication. And lastly, some adults with depression might require long-term treatment to prevent recurrence after remission.
He mentioned a more vigilant approach to diagnosing mental health disorders, originally suggested by Laura Batstra, Ph.D., and Dr. Allen Frances, "which allows clinicians to avoid labeling subthreshold symptoms and mild conditions with psychiatric diagnoses" and encourages the use of less intense psychological interventions when appropriate (Psychother. Psychosom. 2012;81:5-10).
Dr. Mojtabai explained that this study underscores the challenge of accurately diagnosing mental disorders, and as primary care starts to play a larger role in mental health care, special priority should be given to improved diagnosis and treatment of psychiatric conditions.
Dr. Mojtabai disclosed receiving consulting fees from Lundbeck Pharmaceuticals.
mrajaraman@frontlinemedcom.com
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