Introduction: Psychosis is a multifaceted clinical phenomenon in which the various symptoms may show a differential response to treatment. Important information may be lost when heterogeneous symptoms are grouped together in global sum scores when studying treatment effects.Aims: The aim of this study was to compare the level and rate of change in the two separate symptoms hallucinations and delusions during the acute psychotic phase, and to explore whether potential temporal differences depend on diagnosis or patients being previously medicated with antipsychotics or not.Method: Patients admitted with active symptoms of schizophrenia or related psychotic disorders were included in the Bergen Psychosis Project (BPP) (N = 226), a prospective, pragmatic, study of four second-generation antipsychotics. The Positive and Negative Syndrome Scale were assessed at baseline, one, three and six months.Results: Over the total follow-up period, latent growth curve models showed greater reductions in delusions than in hallucinations. However, the percentage of the total reduction was found to be larger in hallucinations than that of delusions in the first interval (91% vs. 64%). The levels and changes in these variables were dependent on diagnosis and whether or not patients had a life-time history of antipsychotic use.Conclusion: Focusing on separate symptoms rather than general symptom clusters could offer clinicians a useful approach when evaluating the early response of antipsychotics.ClinicalTrials.gov ID: NCT00932529; URL: http://www.clinicaltrials.gov/.
Keywords: PANSS; Schizophrenia; antipsychotic medication; antipsychotic naïve; latent growth curve modelling.