Changes in memory performance over a 12-month period in relation to achieving symptomatic remission after a first-episode psychosis

With the introduction of a clear definition of symptomatic remission from the Remission in Schizophrenia Working Group (RSWG), studies have sought to characterize cognitive functioning in remitted and non-remitted schizophrenia patients. However, most investigations of cognition and remission are cross-sectional or have studied samples of chronically ill patients. Therefore, the aim of this study was to compare cognitive performance between remitted and non-remitted first-episode psychosis (FEP) patients longitudinally. Seventy patients were categorized as remitted (n = 17) or non-remitted (n = 53) using the full RSWG criteria after being treated for approximately 15 months, during which cognition was evaluated twice. Since our previous investigations in FEP have isolated verbal memory as a potential cognitive marker of symptomatic remission, analyses were limited to verbal, visual and working memory. We have found that non-remitted patients had a significantly worse verbal memory performance than remitted patients after 3 months (F(1,68) = 6.47, p = 0.006) and 15 months of treatment (F(1,68) = 19.49, p < 0.001). Visual memory was also significantly lower in non-remitted patients compared to those in remission but only at initial assessment (F(1,68) = 8.21, p = 0.003) while working memory performance was similar at both time points. Our findings suggest that verbal memory may be a specific and stable marker of clinical remission in FEP patients. This cognitive domain can easily be evaluated at treatment intake in the hope of identifying early on patients who are less likely to remit.