Can we predict relapse in single episode psychosis patients with stable maintenance treatment for at least one year?

Abstract

Introduction: Medication discontinuation in remitted single episode patients after a period of maintenance therapy is a major clinical decision and therefore the identification of risk factors controlling for medication status is important.Methods: Following a first/single episode with DSM-IV schizophrenia and related psychoses, remitted patients who had remained well on mainte-nance medication for at least 1 year were randomized to receive either maintenance therapy (with quetiapine 400 mg/day), or placebo for 12 months.Results: A total of 178 patients were randomized into quetiapine (n = 89) or placebo groups (n = 89). Potential predictors were initially identified in univariate Cox regression models (p < 0.1) and were subsequently entered into a multivariate Cox regression model for measuring the relapse risk. Significant relapse predictors were placebo treatment (hazard ratio, 0.349; CI, 0.202–0.601), pre-morbid schizoid and schizotypal traits (hazard ratio, 3.081; CI, 1.712–5.545), logical memory (hazard ratio, 0.913; CI, 0.86–0.969), blink rate (hazard ratio, 1.009, CI, 1.002–1.016) and schizophrenia diagno-sis (hazard ratio, 1.816; CI, 1.096–3.008).Conclusions: Current data on relapse predictors may help to inform clini-cal decisions about discontinuation of maintenance therapy specifically for patients with a first/single episode psychosis following at least 1 year of maintenance therapy. However, predictive capacity of them is relatively modest and further work will be required to identify more powerful predictors.Acknowledgement: The study was supported by investigator initiated trial award from AstraZeneca and the Research Grants Council Hong Kong (Project number: 765505).