Risk factors for relapse following treatment for first episode psychosis: a systematic review and meta-analysis of longitudinal studies

Background: Preventing relapse is an essential element of early intervention in psychosis, but relevant risk factors and precise relapse rates remain to be clarified. The aim of this study was to systematically compile and analyse risk factors for and rates of relapse in the early course of psychosis.

Methods: Systematic review and meta-analysis of English and non-English language, peer-reviewed, longitudinal studies, with a minimum 12-month follow-up and at least 80% of participants diagnosed with a first episode of psychosis (FEP) that reported risk factors for relapse.

Results: Of 153 potentially relevant articles, 29 were included in the study. Pooled prevalence of relapse of positive symptoms was 28% (range=12-47%), 43% (35-54%), 54% (40-63%) at 1, 1.5-2, and 3 years follow-up, in that order. A total of 109 predictors were analysed, with 24 being assessed in at least 3 studies. Of those, 20 predictors could be extracted for meta-analysis. Medication non-adherence, persistent substance use disorder, carers' critical comments (but not overall expressed emotion) and poorer premorbid adjustment, increased the risk for relapse 4-fold, 3-fold, 2.3-fold and 2.2-fold, respectively.

Conclusions: Clinical variables and general demographic variables have little impact on relapse rates. Conversely, non-adherence with medication, persistent substance use disorder, carers' criticism and poorer premorbid adjustment significantly increase the risk for relapse in FEP. Future studies need to address the methodological limitations of the extant research (e.g. definition of relapse), focus on the identification of protective factors and evaluate theoretically derived models of relapse.