Personality, stressful life events, and treatment response in Major Depression.

摘要

Major Depression (MD) currently affects over 17 million individuals in North America (Greenberg et al., 2003). Identifying factors predictive of MD treatment response is important for developing more efficacious treatments and better understanding MD vulnerability. The goal of the present study was to examine the main and interactive effects of personality and stressful life events as predictors of MD treatment response. One hundred and thirty-one clinically depressed participants were randomly assigned to either 16-weeks of cognitive behavioural therapy (CBT), interpersonal psychotherapy (IPT), or pharmacotherapy (PT). Personality in the form of trait self-criticism, neediness, and connectedness was assessed at pre and post-treatment using the Depressive Experiences Questionnaire (DEQ; Blatt et al., 1976). Stressful life events experienced during treatment were assessed using the Life Events and Difficulties Schedule (LEDS; Bifulco et al., 1989). Results revealed that amongst individuals scoring lower in pre-treatment self-criticism, higher pre-treatment connectedness predicted superior treatment response. As well, amongst individuals scoring lower in pre-treatment neediness, higher pre-treatment connectedness predicted superior treatment response. In terms of personality change, both a reduction in neediness and a reduction in self-criticism over the course of treatment predicted superior treatment response. A personality x stressful life event interaction was also found such that amongst those experiencing a stressful life event during treatment, higher scores on pre-treatment self-criticism predicted poor treatment response. These results suggest that personality and stressful life events play an important role in the treatment of MD. Limitations and clinical implications are discussed.