Young adults at risk for suicide when taking high doses of SSRI antidepressants
May 1, 2014
Antidepressant therapy has long been associated with increased risk of suicide in people under 25. There has not been a clear reason why some drugs are more likely than others to have this result and why only a subset of the young adult population is vulnerable.
A collaboration of researchers at The University of North Carolina at Chapel Hill and Harvard schools of public health has found that one reason for increased suicide risk occurs when young patients are started at a higher dose than is recommended.
Dr. Til Stürmer
The study, led by Til Sturmer, MD, PhD, professor of epidemiology and director of the UNC Center for Pharmacoepidemiology at the UNC Gillings School of Global Public Health, and Matthew Miller, MD, DSc, associate professor of health policy and management at Harvard School of Public Health, was published online April 28 in the Journal of the American Medical Association Internal Medicine.
The authors reviewed information on 162,625 people in the U.S., ages 10 to 64 years, who had initiated antidepressant therapy with selective serotonin reuptake inhibitors (SSRI) between 1998 and 2010. They then used medical claims – at one-month, three-month and one-year intervals after first prescription – to assess the incidence of suicide attempts.
The particular SSRIs analyzed were citalopram hydrobromide (Celexa) sertraline hydrochloride (Zoloft) and fluoxetine hydrochloride (Prozac), as those three drug formulations were prescribed in 67 percent of those initiating SSRIs.
In children and adults 24 years and younger, the researchers found the rate of deliberate self-harm to be twice as high among those who began with high doses of antidepressant therapy, as compared with those who began with modal, or median, doses. In adults ages 25 to 64 years, the overall risk of suicidal behavior was far lower and the difference between high-dose vs. modal-dose risk negligible.
Findings from the study, the authors say, “offer clinicians an additional incentive to avoid initiating pharmacotherapy at high-therapeutic doses and to closely monitor patients starting antidepressants, especially youth, for several months.”
The article is accompanied by an editorial by David A. Brent, M.D., of the University of Pittsburgh, and Robert Gibbons, PhD, of the University of Chicago, highlighting the sound methodology of the study and the importance of the findings.
Co-authors in addition to Sturmer and Miller are Sonja A. Swanson, ScM, of the Harvard School of Public Health’s Department of Epidemiology; Deborah Azrael, PhD, of Harvard’s Department of Health Policy and Management; and Virginia Pate, MSc, of the UNC Gillings School’s Department of Epidemiology.
Gillings School of Global Public Health contact: David Pesci, director of communications, (919) 962-2600 or dpesci@unc.edu.
