Suicide risk factors consistent across nations

Risk factors for suicidal thoughts, plans and attempts are consistent across countries, and include having a mental disorder and being female, younger, less educated, and unmarried. So says new research from a Harvard University professor and the World Health Organization (WHO) World Mental Health Survey Initiative. The study examined both the prevalence and the risk factors for suicide across 17 countries, and is the largest, most representative examination of suicidal behavior ever conducted.

Published in the February issue of the “British Journal of Psychiatry,” the study was led by Matthew Nock, associate professor of psychology in the Faculty of Arts and Sciences at Harvard, with data collected by the WHO World Mental Health Survey Initiative.

“Our research suggests that suicidal thoughts and behaviors are more common than one might think, and also that key risk factors for these behaviors are quite consistent across many different countries around the world,” says Nock.

Among those interviewed, 9.2 percent reported that they had seriously thought about suicide and 2.7 percent reported making a suicide attempt at some point in their lives. However, there was variation from country to country with regard to the rates of suicidal thoughts and behaviors. For instance, rates of suicidal thoughts ranged from 3.1 percent of people in China to 15.9 percent in New Zealand. A possible reason for this variation may be that different cultural standards exist with regard to the acceptability of telling others about suicidal thoughts. Therefore, among countries with lower rates of suicidal thoughts, it’s possible that some thoughts of suicide were not reported.

Across the countries included in the study, risk factors for suicidal behavior included female gender, younger age, fewer years of education, unmarried status and the presence of a mental disorder. Additionally, the risk of suicidal thoughts increased sharply during adolescence and young adulthood in every country studied.

The strongest risk factor associated with suicidal thoughts and behaviors were mood disorders in high income countries and impulse control disorders in low- and middle-income countries.

“We often think of suicidal thoughts and behaviors as occurring among people who are depressed, but across all of these countries, we found that it is not just depression that increases the risk of suicidal behaviors—impulse control disorders, substance use disorders, and anxiety disorders all are associated with a significantly higher risk of suicidal thoughts and attempts,” says Nock.

In fact, this study showed that among people with suicidal thoughts, the risk of making an attempt was highest not among those with a mood disorder, but in those with substance abuse and impulse-control disorders, suggesting that these disorders are most strongly associated with acting on suicidal thoughts when they are present.