a1 Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, St Louis, MO, USA
a2 Department of Epidemiology and Public Health, Queensland Institute for Medical Research, Brisbane, Australia
Background Few genetically informative studies have examined the effects of different types of trauma on risk for depression over time. The aim of the present study was to examine the relative contributions over time of assaultive trauma, non-assaultive trauma, and familial effects to risk for depression.
Method Histories of depression and trauma were obtained during structured diagnostic interviews with 5266 (mean age 29.9 years, s.d.=2.4) members of a volunteer Australian twin panel from the general population. Age at first onset of a DSM-IV major depressive episode was the dependent variable. Associations of depression with traumatic events were examined while accounting for the temporal sequence of trauma and depression and familial effects.
Results Assaultive traumatic events that occurred during childhood had the strongest association with immediate and long-term risk for depression, and outweighed familial effects on childhood-onset depression for most twins. Although men and women endorsed equal rates of assaultive trauma, women reported a greater accumulation of assaultive events at earlier ages than men, whereas men reported a greater accumulation of non-assaultive events at all ages.
Conclusions Early exposure to assaultive trauma can influence risk for depression into adulthood. Concordance for early trauma is a significant contributor to the familiality of early-onset depression.
(Received January 29 2008)
(Revised April 25 2008)
(Accepted May 03 2008)
(Online publication June 04 2008)
c1 Address for correspondence: V. V. McCutcheon, Ph.D., Midwest Alcoholism Research Center, Department of Psychiatry, Washington University School of Medicine, 660 South Euclid Ave., Campus Box 8134, St Louis, MO 63110, USA. (Email: firstname.lastname@example.org)
Portions of this paper were presented as a poster at the 97th Annual American Psychopathological Association Meeting, New York, NY, 1 March 2007, and were based in part upon work completed for the first author's doctoral dissertation in Social Work at Washington University.