Triggers or aggravators of symptoms?

This study attempts to replicate and extend the associations reported by Verbrugge among negative events, bad mood and symptoms. Employing the same symptomatology measure used in that study, but with more comprehensive event and mood questionnaires, we essentially replicated the same-day and lagged relationships reported by Verbrugge. One difference, however, was that undesirable events were a stronger predictor of symptom days than negative mood, whereas the opposite was true in Verbrugge's study. To further investigate the causal role of events and mood on symptoms, analyses were performed looking only at onset days of symptom episodes. This procedure greatly reduced same day event-symptom associations and eliminated event and mood's lagged relationships with symptoms. Our results do not, then, corroborate the triggering effect of events and mood for the onset of symptoms, although these variables may have a role in maintaining the duration of symptom episodes.