Rapid emotional swings could precede violence

A tool from physics helps link patterns of psychiatric patients’ symptoms and the likelihood they will commit violent acts

Predicting whether patients with mental disorders will become violent is a dicey business, and one the legal system has thrust upon mental-health workers. A new study encouragingly suggests that swift swings in the intensity of symptoms can often peg which psychiatric patients are on the verge of threatening or hurting others.

Employing a statistical technique called dynamic systems modeling, the new work shows that among psychiatric patients with documented histories of committing violent acts, those whose symptoms of emotional distress rapidly and repeatedly fluctuated from mild to severe during a 26-week period were particularly apt to assault others or to threaten them with a weapon, say psychologist Candice Odgers of the University of California, Irvine and her colleagues.

In cases of rapid symptom fluctuation, patients went from peaks to valleys of emotional health about every two to four weeks, the team reports in a paper published online April 15 and slated to appear in the American Journal of Psychiatry.

Violence occurred less frequently among patients whose symptoms fluctuated from high to low points over longer stretches, which often lasted about 10 weeks.

Overall, patients whose symptoms rapidly ebbed and flowed were almost three times as likely to become violent than those whose symptoms oscillated slowly. Patients who displayed rapidly fluctuating psychiatric symptoms that also worsened during the study were especially likely to commit two or more violent acts during the study period.

Psychologist John Monahan of the University of Virginia in Charlottesville calls the new paper “one of the most original and important studies on psychiatric symptoms and violence published in the past decade.” Monahan has studied the relationship between psychiatric disorders and violence for more than 30 years.

“Our initial findings are promising,” Odgers says, “and may provide a new window into understanding the interplay between psychiatric symptoms and violence.”

Although researchers know that psychiatric symptoms typically wax and wane, earlier studies have examined only whether symptoms present at one point in time predict violence at a later point. Odgers’ team used the dynamic systems models to analyze change processes. Physicists use dynamic systems models to study processes such as shifts from fluid to solid and back again. Developmental psychologists have adapted this approach to examine milestones of individual development, such as ways in which infants go from crawling to walking.

Odgers and her coworkers studied 132 adults for 26 weeks after they were treated and released from a psychiatric hospital emergency room in 2000. Record reviews showed that all participants exhibited intense hostility and, in the two months before treatment, had heavily used alcohol and illicit drugs and had been involved in serious violence. Patients’ violent acts involved physical injuries, sexual assault or the use of weapons.

Each week during the study, the researchers interviewed a close family member or friend of each patient, as well as the patients themselves, for information on participants’ recent symptoms and violent behaviors. By the end of the 26 weeks, 78 patients had committed at least one violent act.

Although the new findings are intriguing, further research must clarify what percentage of psychiatric patients’ violent acts are accurately predicted by rapidly fluctuating and worsening symptoms, remarks psychiatrist Paul Appelbaum of Columbia University. Since Odgers’ team collected data on symptoms and violent acts at the end of each week, it’s possible that symptom fluctuations followed, rather than preceded, violence, Appelbaum notes.

In further research, Odgers plans to examine whether rapid symptom fluctuations begin before or after patients commit violent acts. She also wants to explore the relationship between symptom swings and stressful events, including job loss and fights with romantic partners. 

“Even if amplification and rapid oscillation of symptoms are ultimately shown to precede violence, they will not be useful as predictors unless symptom changes give clinicians at least a week’s warning,” Appelbaum says. Clinicians simply don’t have the resources to monitor and treat symptom fluctuations that speed up a few days or hours before violence flares up, he asserts.

Many factors, including hostility and paranoia, are already known to make small but statistically significant contributions to predicting whether psychiatric patients will commit violence, Appelbaum notes.

While it’s still difficult to predict which psychiatric patients will actually become violent, “Odgers and her colleagues have opened up an entirely new and potentially fruitful way to approach violence risk assessment,” Monahan says.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.

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