Low Intelligence Test Scores in 18 Year old men and Risk of Suicide: Cohort Study

The authors studied the association between intelligence test scores & subsequent suicide in 987,308 Swedish men measured at age 18 & followed up for 5-26 years. 2811 suicides occurred during follow up. The risk of suicide was 2 to 3 times higher in those with the lowest compared with the highest intelligence test scores. The strongest associations were seen with the logic test: for each unit increase in test score the risk of suicide decreased by 12%. Greatest risks were seen among poorly performing offspring of well educated parents. (15 refs)