Additive effects between prematurity and postnatal risk factors of suicidal behavior

Background: Pre- and perinatal insults increase suicide risk. The main objective of the present study is to investigate if prematurity interacts in an additive fashion with postnatal risk factors of suicidal behavior. Method: Sample and procedure: 857 adult suicide attempters consecutively hospitalized for a suicide attempt were included. Studied characteristics of suicide attempts included use of a violent mean, age at first suicide attempt, and number of suicide attempts. Risk factors of suicidal behavior included indexes of pre- and perinatal adversity, childhood maltreatment as measured with the Childhood Trauma Questionnaire, personality traits as measured with the Tridimensional Personality Questionnaire, and family history of suicidal behavior. Statistical analyses: Comparisons between the different patterns of suicide attempts characteristics were made using logistic regression with crude and adjusted odds ratios and 95% confidence intervals. Results: The risk of violent suicide attempts increased significantly in patients born prematurely (OR [95%] = 2.38[1.12-5.081). There were additive effects for very preterm birth and 1) emotional abuse (OR [95% CI] = 4.52 [1.75-11.601), 2) novelty seeking (OR [95% CI] = 8.92[3.09-25.7]), and 3) harm avoidance (OR [95% CI] = 5.81 [2.43-13.90]) on the age at first suicide attempt, after adjustment for potential confounders. Conclusions: Very preterm birth appears to be the first step in a cascade of stressors across lifetime, which affects the risk and the severity of suicidal behavior. Furthermore, very preterm birth, childhood maltreatment and personality traits have additive effects that influence the age at onset of suicide attempt. Our findings may have potential consequences for preventive policies. (C) 2013 Elsevier Ltd. All rights reserved.