Remission in schizophrenia: critical and systematic review

In 2005, the Remission in Schizophrenia Working Group published consensus criteria to define remission. These criteria have been widely accepted and utilized and have provided further insights about schizophrenia management and prognosis. We systematically reviewed studies that utilized these criteria, with the aim of assessing the remission rate in follow-up studies and the variables predicting or associated with remission. Remission has a reported rate of 17% to 78% (weighted mean = 35.6%) in first-episode schizophrenia and 16% to 62% (weighted mean = 37%) in multiple-episode patients, with no statistical difference between the two weighted means (p = .79). Patients who were treated with long-acting injectable risperidone showed high maintenance of remission status. Studies comparing second-generation antipsychotics versus haloperidol showed higher remission rates for the former. The variables most frequently associated with remission were better premorbid function, milder symptoms at baseline (especially negative symptoms), early response to treatment, and shorter duration of untreated psychosis. Variability in the length and frequency of follow-ups, as well as differences in dropout rates, could partially explain the differences in reported rates. Rates of symptomatic remission exceeded reported rates for functional recovery. Moreover, the majority of studies used Remission in Schizophrenia Working Group severity criteria only, neglecting duration. To enhance comparison between future research findings, we suggest further specifiers of the working group's criteria, to better define frequency and duration of follow-up, and proxy measures of remission.