A one year prospective study of the effect of life events and medication in the aetiology of schizophrenic relapse

Background. We set out to determine whether and to what degree life events independent of illness increase the risk of relapse in schizophrenia following withdrawal from medication in the previous 6 months, either by triggering a relapse in the following 4 weeks or by acting cumulatively over time. Method. Seventy-one patients fulfilling DSM-III-R criteria for schizophrenia with chronic illness were followed for 48 weeks and assessed on the LEDS scale. Half were treated with regular neuroleptic medication and half had been recently withdrawn from medication. A subgroup was randomised double-blind to treatment or placebo. Results. A proportional hazards regression model showed that life events made a significant cumulative contribution over time (P < 0.05) to the risks of relapse and that ceasing medication made an independent contribution. The risk of relapse increased in proportion to the number of life events but no interaction between medication status and events could be detected, i.e. life events were not more closely associated with relapse on medication than off medication. For those of the sample exposed to the mean rate of life events during the study period, it was estimated that 23% of the relapse risk could be attributed to life events, and for those with twice the mean rate of events, 41%. In contrast, patients who continued on regular medication had 80% less risk of relapse than those who had been withdrawn from medication either by choice or under double-blind controlled conditions. Conclusion. A contribution of life events to the risk of relapse in schizophrenia was confirmed by this study but the hypothesis that life events trigger relapse was not supported, nor was the hypothesis that life events are more relevant to relapse in patients on maintenance medication than in patients off medication.