Psychological Medicine

Original Article

Early childhood factors associated with the development of post-traumatic stress disorder: results from a longitudinal birth cohort

a1 Department of Society, Human Development, and Health and Epidemiology, Harvard School of Public Health, Boston, MA, USA
a2 Department of Psychiatry, Boston University Medical Center, Boston, MA, USA
a3 Social, Genetic, and Developmental Psychiatry Research Centre, Institute of Psychiatry, King's College London, London, UK
a4 Department of Psychology, University of Wisconsin–Madison, USA
a5 Dunedin Multidisciplinary Health and Development Research Unit, Dunedin, New Zealand
a6 Department of Psychological Medicine, University of Otago, Dunedin, New Zealand

Article author query
koenen kc   [PubMed][Google Scholar] 
moffitt te   [PubMed][Google Scholar] 
poulton r   [PubMed][Google Scholar] 
martin j   [PubMed][Google Scholar] 
caspi a   [PubMed][Google Scholar] 


Background. Childhood factors have been associated with increased risk of developing post-traumatic stress disorder (PTSD). Previous studies assessed only a limited number of childhood factors retrospectively. We examined the association between childhood neurodevelopmental, temperamental, behavioral and family environmental characteristics assessed before age 11 years and the development of PTSD up to age 32 years in a birth cohort.

Method. Members of a 1972–73 New Zealand birth cohort (n=1037) who were assessed at ages 26 and 32 years for PTSD as defined by DSM-IV.

Results. We identified two sets of childhood risk factors. The first set of risk factors was associated both with increased risk of trauma exposure and with PTSD assessed at age 26. These included childhood externalizing characteristics and family environmental stressors, specifically maternal distress and loss of a parent. The second set of risk factors affected risk for PTSD only and included low IQ and chronic environmental adversity. The effect of cumulative childhood factors on risk of PTSD at age 26 was substantial; over 58% of cohort members in the highest risk quartile for three developmental factors had PTSD as compared to only 25% of those not at high risk on any factors. Low IQ at age 5, antisocial behavior, and poverty before age 11 continued to predict PTSD related to traumatic events that occurred between the ages of 26 and 32.

Conclusions. Developmental capacities and conditions of early childhood may increase both risk of trauma exposure and the risk that individuals will respond adversely to traumatic exposures. Rather than being solely a response to trauma, PTSD may have developmental origins.

(Published Online October 20 2006)

c1 Department of Society, Human Development, and Health, Harvard School of Public Health, 677 Huntington Avenue, Kresge 613, Boston, MA 02115, USA. (Email: