Post-traumatic stress disorder has been on psychiatry's books for just 23 years, and before the terrorist attacks of Sept. 11, 2001, no one ever entertained the possibility that watching disturbing images of trauma on TV could give rise to the disorder.
The notion remains controversial, but new research suggests that PTSD might indeed be transmitted over the airwaves. The study finds that those who spent more than six hours a day watching media coverage of the April 15 Boston Marathon bombing and its aftermath suffered more powerful stress reactions than did people who were directly involved but watched less news coverage of the events.
The study was published Monday in the journal PNAS.
Two to four weeks after the Boston Marathon bombings, researchers reached out to a nationwide cohort of 4,675 Americans who complete Web-based surveys in exchange for compensation or free Internet access, to gauge their lingering stress reactions and their media exposure in the wake of the bombings. The survey-takers were a representative sample of metropolitan Boston, New York City and the rest of the United States.
The heavy sampling of New Yorkers allowed researchers to test what impact exposure to a past community trauma would have on media consumers of Boston bombing coverage.
As much as a month after the Boston bombings, roughly 4.5% of respondents were reporting symptoms that met the psychiatric criteria for "high acute stress." After the researchers adjusted for the effects of direct exposure to a trauma and for exposure to past community trauma, they found that respondents with a prior history of mental health problems and those who had watched six or more hours of daily media coverage of the events surrounding the bombings were most likely to report high acute-stress symptoms.
Direct exposure to the bombings -- having been there or being in a close relationship with someone who was affected -- was a strong predictor of ongoing stress reactions. Another strong predictor was direct exposure to the events of Sept. 11 or the Dec. 14, 201,2 shootings at Sandy Hook Elementary School in Newtown, Conn. (but not to Superstorm Sandy, which devastated the New Jersey coast in October 2012).
But the single factor that most strongly predicted high stress reactions was having watched six or more hours a day of media coverage of the bombings and their aftermath.
The authors of the study, all from University of California, Irvine, suggested that 24/7 media coverage of traumatic events may exacerbate stress reactions among those who are already vulnerable to post-traumatic stress disorder by virtue of a past history of mental illness or past experience of traumas. Intensive viewing of such media coverage could not only sustain trauma reactions after they should begin to abate; it could "unintentionally spread negative impacts beyond the directly exposed area," they warned.
The authors acknowledged their findings do not demonstrate a cause-and-effect relationship between intensive consumption of media coverage of a trauma and PTSD. But they pointed to their own findings of post-traumatic stress after Sept. 11: that three years after those terrorist attacks, those who reported watching the most Sept. 11 coverage had the heaviest load of post-traumatic stress symptoms, such as intrusive thoughts, nightmares, anxiety triggered by cues associated with the incident and physical symptoms including sleep troubles and headaches.
The most plausible interpretation of the study's findings, say the authors, is that media coverage can be an unhelpful factor for those predisposed to PTSD in the first place.
"People who are most distressed in the aftermath of such an event are probably more likely to engage media coverage as a way of coping with the experience," they wrote. "Although this may be beneficial initially, over time the repeated media-based reexposures may contribute to a self-perpetuating cycle of distress."