Background. Life events (LE) have consistently been found to influence course and outcome of psychotic disorders. However, the mechanism through which they operate is not known. The present study investigated whether LE have their effect by impacting on the emotional sensitivity for daily hassles.

Method. Patients with clinically remitted psychotic illness (N=42) were studied with the Experience Sampling Method (a structured diary technique assessing current context and mood in daily life) to assess: (1) appraised subjective stress related to daily events and activities; and (2) emotional reactivity conceptualized as changes in both negative affect (NA) and positive affect (PA). LE were assessed with the Brown & Harris Life Event and Difficulties Schedule.

Results. Multilevel regression analyses showed that previous exposure to LE influenced the appraised stressfulness of neither daily events nor the activities in which the subjects were involved. However, a history of LE did modify the emotional reaction to daily life stress, both in models predicting NA and in models predicting PA.

Conclusions. By their cumulative effect on emotional reactivity to daily activities and events, LE may render individuals more vulnerable to the onset or persistence of psychotic experiences.