Citation

Batty GD, Whitley E, Deary IJ, Gale CR, Tynelius P, Rasmussen F. Br. Med. J. BMJ 2010; 340(online): c2506.

Affiliation

Medical Research Council Social and Public Health Sciences Unit, University of Glasgow, Glasgow.

Copyright

(Copyright © 2010, BMJ Publishing Group)

DOI

unavailable

PMID

20522657

PMCID

PMC2881197

Abstract

OBJECTIVES: To explore associations between IQ measured in early adulthood and subsequent hospital admissions for attempted suicide and to explore the role of psychosis and examine associations of IQ with specific methods of attempted suicide. DESIGN: Cohort study. SETTING: Sweden. PARTICIPANTS: 1 109 475 Swedish men with IQ measured in early adulthood followed up for an average 24 years. MAIN OUTCOME MEASURES: Hospital admission for attempted suicide. RESULTS: 17 736 (1.6%) men had at least one hospital admission for attempted suicide by any means during follow-up. After adjustment for age and socioeconomic status, lower IQ scores were associated with an elevated risk of attempted suicide by any means (hazard ratio per standard deviation decrease in IQ=1.57, 95% confidence interval 1.54 to 1.60), with stepwise increases in risk across the full IQ range (P for trend<0.001). Similar associations were observed for all specific methods of attempted suicide. Separate analyses indicated that associations between IQ and attempted suicide were restricted to participants without psychosis and that IQ had no marked impact on risk of attempted suicide in those with psychosis. CONCLUSIONS: Low IQ scores in early adulthood were associated with a subsequently increased risk of attempted suicide in men free from psychosis. A greater understanding of the mechanisms underlying these associations may provide opportunities and strategies for prevention.

Language: en