Background: Predominant negative symptoms (PNSs) in schizophrenia can affect the patients' psychosocial functioning immensely and are less responsive to treatment than positive symptoms.
Aims: The aim of the study was to observe negative symptoms and psychosocial functioning in PNS schizophrenia patients and to understand whether PNS can be improved and with what treatment strategies.
Methods: This was a 1-year, prospective, multicentric cohort study conducted in Slovakia. Adult outpatients with diagnosis of schizophrenia according to ICD-10 and PNS evaluated using the criteria by the European Psychiatric Association's (EPA) guidance were included. Change in negative symptoms, functionality, and treatment patterns were observed. Treatment effectiveness was evaluated using the modified Short Assessment of Negative Domain (m-SAND), the Self-evaluation of Negative Symptoms (SNS) scale, the Personal and Social Performance (PSP) scale, and the Clinical Global Impression - Severity (CGI-S) and the Clinical Global Impression - Improvement (CGI-I) scales. Least-squares (LS) means were calculated for the change from baseline to final visit for the outcomes.
Results: The study included 188 patients. Functionality improved as, by the end of the study, fewer patients were unemployed (53%) and more worked occasionally (21%). PNS improved significantly according to both physicians and patients (LS mean change from baseline in m-SAND total score: -10.0 (p-value <0.0001)). Most patients received polytherapy throughout the study. Cariprazine was utilized most (20% monotherapy and 76% polytherapy). Only a few patients discontinued treatment due to adverse drug reactions.
Conclusions: With the right treatment strategy, it is possible to achieve improvement in PNS and everyday functioning in schizophrenia outpatients.
Keywords: antipsychotic medication; negative symptoms; observational study; schizophrenia.