Classmate suicide increased risk of suicide consideration, attempt

Youth who had a classmate commit suicide are more likely to consider or attempt suicide, according to findings in a recent study published in the Canadian Medical Association Journal.

“We found that exposure to suicide predicts suicidality,” researchers wrote. “This was true for all age groups, although exposure to suicide increased the risk most dramatically in the youngest age group, when baseline suicidality was relatively low.”

The study included 8,766 youth aged 12 to 13 years, 7,802 aged 14 to 15 years and 5,496 aged 16 to 17 years, using data from the Canadian National Longitudinal Survey of Children and Youth between 1998 and 1999 and 2006 and 2007 with 2-year follow-ups.

Researchers found that exposure to a classmate's suicide was linked to suicide ideation among youth aged 12 to 13 years (OR=5.06; 95% CI, 3.04-8.40), 14 to 15 years (OR=2.93; 95% CI, 2.02-4.24) and 16 to 17 years (OR=2.23; 95% CI, 1.43-3.48). Attempts of suicide also were more likely among those aged 12 to 13 years (OR=4.57; 95% CI, 2.39-8.71), 14 to 15 years (OR=3.99; 95% CI, 2.46-6.45) and 16 to 17 years (OR=3.22; 95% CI, 1.62-6.41).

At the 2-year follow-up of participants aged 12 to 15 years, a classmate’s suicide was still related to suicide attempts among those aged 12 to 13 years (OR=3.07; 95% CI, 1.05-8.96) and 14 to 15 years (OR=2.72; 95% CI, 1.47-5.04).

The researchers said they were surprised to find that the effect of being exposed to a schoolmate's suicide on suicidal thoughts or behavior was equally strong among those who personally knew the deceased and those who did not.

“Our findings support school- or community-wide interventions over strategies targeting those who personally knew the decedent, suggests that allocating resources following an event may be especially important during adolescence, and implies that schools and communities should be aware of an increased risk for at least 2 years following a suicide event,” the researchers wrote.

In an editorial accompanying the study, India Bohanna, PhD, of James Cook University in Australia, wrote that the study shows how important it is to include everyone exposed to suicide when post-intervention strategies are developed.

“The idea that suicide is contagious has always been controversial for various reasons; however this important study should put many, if not all, doubts to rest,” Bohanna wrote.

For more information:

Bohanna I. CMAJ. 2013;doi:10.1503/cmaj.130678.

Swanson SA. CMAJ. 2013;doi:10.1503/cmaj.121377.

Disclosure: The researchers report no relevant financial disclosures.