Effects of negative life experiences on phobia onset

Background: Conditioning theories, stress theories and social psychological theories each suggest that negative life experiences should influence phobia onset, though the patterns of effects suggested by each type of theory are different. Few previous studies have estimated the effects of a broad enough range of life experiences on onset of multiple types of phobia to evaluate patterns of effects. Methods: Retrospective data on life experiences and history of phobia from a representative sample of persons 15-54 years old from the US population (the National Comorbidity Survey) are analyzed using discrete-time event history methods. Results: The effects of 12 negative life events and ten chronic childhood adversities on onset of agoraphobia, specific phobia, and social phobia are presented. Three discrete events have unique effects on agoraphobia onset: life threatening accidents, combat in war (for men), and a fire/flood or other natural disaster. Two chronic experiences during childhood have unique effects on specific phobia onset: violence at the hands of one or more adults, and verbal aggression between parents. Sexual assault by a relative and verbal aggression between parents have unique effects on social phobia onset. The effect of sexual assault by a relative on social phobia is confined to women, and to phobias beginning before age 12. Conclusions: Unpredictable and uncontrollable events that threaten or result in physical harm influence agoraphobia onset. Potentially predictable but difficult to control childhood experiences (e.g., chronic parental violence) influence specific phobia onset. Blame is a likely mediator of the effect of sexual abuse on social phobia. No data on perceptions of predictability and controllability of life experiences, or of blame, were available for analysis. These conclusions are therefore based on speculations about social psychological processes that have been supported by previous research and theory.