Remission criteria and functional outcome in patients with schizophrenia, a longitudinal study

Abstract

Background: The Remission in Schizophrenia Working Group (RSWG) has proposed remission criteria for schizophrenia, which were shown to be valid in terms of functional and clinical outcomes. However, studies investigating the association between dynamics in remission status in relation to longitudinal functional and clinical outcome are scarce. Methods: A total of 648 patients were allocated to four change-in-remission groups, i.e. remission/remission, remission/no-remission, no-remission/remission, and no-remission/no-remission. Remission status was based on PANSS ratings. Multilevel linear modelling techniques were used to investigate whether enduring remission was associated with more improvement in functional outcome at follow-up. Further, change in functional and clinical outcome at follow-up measurement was assessed for each remission category separately. Results: Both at baseline and at follow-up, remission status was associated with better functioning. At baseline, patients who subsequently moved out of remission status could be characterized by more severe psychopathology, disabilities, unmet needs and worse quality of life (QoL) compared with patients who continued to be in remission. The stable in-remission group was characterized by significantly better functioning and QoL, both at baseline and follow-up compared with all other remission groups. Nevertheless, QoL increased in all four patient categories. Conclusions: In a large sample of patients with a non-affective psychotic disorder, stable remission or moving into remission over time, based on the RSWG criteria, was associated with a favourable functional outcome and QoL, providing further support for the clinical validity of the RSWG remission criteria. The findings also suggest growing adaptation and self-management over time, despite ongoing difficulties.