With the exception of studies of individual traumatic events, the significance
of stress exposure in psychiatric disorder previously has not been effectively
To address the hypothesis that accumulated adversity represents an important
risk factor for the subsequent onset of depressive and anxiety disorders.
A community-based study of psychiatric and substance use disorders among
a large, ethnically diverse cohort representative of young adults in South
Florida. Adversity was estimated with a count of major and potentially traumatic
events experienced during one's lifetime and prior to the onset of disorder.
Most interviews took place in the homes of participants, with 30% conducted
We obtained a random sample of individuals aged 18 to 23 years from
a previously studied representative sample of young adolescents. Because participants
in the prior study were predominantly boys, a supplementary sample of girls
was randomly obtained from the early-adolescence school class rosters. A total
of 1803 interviews were completed, representing a success rate of 70.1%.
Main Outcome Measures
Depressive and anxiety disorders were assessed through computer-assisted
personal interviews using the DSM-IV version of the
Michigan Composite International Diagnostic Interview.
Level of lifetime exposure to adversity was found to be associated with
an increased risk of subsequent onset of depressive and/or anxiety disorder.
This association remained clearly observable when childhood conduct disorder,
attention-deficit/hyperactivity disorder, prior substance dependence, and
posttraumatic stress disorder were held constant and when the possibility
of state dependence effects was considered.
Evidence suggests that high levels of lifetime exposure to adversity
are causally implicated in the onset of depressive and anxiety disorders.