PhD, University of Cincinnati, 2012, Medicine: Biostatistics (Environmental Health)

Background: Schizophrenia is a highly heterogeneous disorder with positive and negative symp-toms construed as distinct characteristic manifestations of the disease. Current antipsychotics work primarily by relieving positive symptoms; while negative symptoms are thought hard to treat. However, little is known about the heterogeneity and pattern of negative symptom response with respect to its linkage with the change in positive symptoms. This research work examined the temporal interplay between positive- and negative-symptom trajectories over a 1-year period in schizophrenic patients under antipsychotic treatment, and evaluated the potential utility of patient subgroups defined by the combined symptom trajectories. Methods: This post hoc analysis used data from an open-label, randomized, 1-year pragmatic trial of patients with schizophrenia spectrum disorder who were treated with first and second generation antipsychotics in the usual clinical settings. Data from all the medications were pooled with 399 patients having complete data on both the positive- and negative- subscale scores from the Positive and Negative Syndrome Scale (PANSS). Individual-based, growth mixture modeling combined with a interplay matrix was used to identify the latent trajectory subgroups in term of both the negative and positive symptoms. Baseline demographics, clinical and functional characteristics were examined among the above identified trajectory subgroups. Results: The negative- and positive-symptom trajectory interplay matrix suggests changes in negative and positive symptoms occurred mostly in tandem in the individual patient. Three ma-jor clinical subgroups were identified: (1) dramatic and sustained early improvement in both negative and positive symptoms (DSI); (2) mild and sustained improvement in negative and positive symptoms (MSI), with greater early improvement in positive rather than in negative symptoms, and (3) no improvement in negative and/or positive symptoms (NI). (open full item for complete abstract)

Committee: Paul Succop PhD (Committee Chair); Haya Ascher-Svanum PhD (Committee Member); Melissa Delbello MD (Committee Member); Kim Dietrich PhD (Committee Member) Subjects: Neurology