People with hostile personality traits who watch more television than their peers may be at a greater risk for injury, potentially because they are more susceptible to the influence of television on violence and risk-taking behaviors, a University of Pittsburgh Graduate School of Public Health analysis discovered.

The research, published online in the International Journal of Injury Control and Safety Promotion, suggests that a reduction in television viewing and content rating systems geared not just to age, but also personality traits, may reduce injury risk.

“Television viewing is very pervasive, with televisions in almost 99 percent of American households. And injuries cause more than half the deaths among people ages 1 through 44. This means that even modest reductions in television viewing, particularly among people predisposed to hostility, could have major positive outcomes for public health,” said lead author Anthony Fabio, Ph.D., M.P.H., assistant professor of epidemiology at Pitt Public Health.

Dr. Fabio and his colleagues analyzed data from 4,196 adults recruited from Birmingham, Ala., Chicago, Minneapolis, and Oakland, Calif., who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. For 15 years starting in 1990, the participants periodically reported their television viewing habits and completed in-depth questionnaires to assess their personality traits. The researchers also recorded all injuries requiring hospitalization.

As the amount of television viewing increased, so did the risk of injuries in the next five years. Notably, this relationship risk was greater for those in the “high hostility” group, which was determined by a scientific questionnaire. For example, for high-hostile individuals, watching more TV at year five was associated with 40 percent higher odds of injury at year 10. Additionally, watching more TV at year 15 was associated with a doubling in the odds of injury at year 20. This association did not occur in individuals with less hostile personalities.

Dr. Fabio and his team point to several research-backed explanations for why increased television watching may be responsible for such a pronounced increase in injuries among people predisposed to hostility, including that:

People often imitate new behaviors that they witness, leading them to participate in more high-risk behaviors if they watch more television.

Media violence and high-risk activities increase psychological arousal, intensifying subsequent behavior, such as aggressive risk-taking or impulsivity.

Images on television may desensitize people to violence or risk-taking.

“Prevention programs should target both the content of television programs and the amount of time people spend watching television,” said Dr. Fabio. “In addition, future studies should be conducted to determine the impact of modifying television viewing habits, particularly in relation to the personality traits of viewers.”