Comparison of patients undergoing switching versus augmentation of antipsychotic medications during treatment for schizophrenia

Haya Ascher-Svanum, Alan JM Brnabic, Anthony H Lawson, Bruce J Kinon, Virginia L Stauffer, Peter D Feldman, Katarina Kelin

Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana, USA

Abstract: It is often difficult to determine whether a patient may best benefit by augmenting their current medication or switching them to another. This post-hoc analysis compares patients’ clinical and functional profiles at the time their antipsychotic medications were either switched or augmented. Adult outpatients receiving oral antipsychotic treatment for schizophrenia were assessed during a 12-month international observational study. Clinical and functional measures were assessed at the time of first treatment switch/augmentation (0–14 days prior) and compared between Switched and Augmented patient groups. Due to low numbers of patients providing such data, interpretations are based on effect sizes. Data at the time of change were available for 87 patients: 53 Switched and 34 Augmented. Inadequate response was the primary reason for treatment change in both groups, whereas lack of adherence was more prevalent in the Switched group (26.4% vs 8.8%). Changes in clinical severity from study initiation to medication change were similar, as indicated by Clinical Global Impressions–Severity scores. However, physical and mental component scores of the 12-item Short-Form Health Survey improved in the Augmented group, but worsened in the Switched group. These findings suggest that the patient’s worsening or lack of meaningful improvement prompts clinicians to switch antipsychotic medications, whereas when patients show some improvement, clinicians may be more likely to try bolstering the improvements through augmentation. Current findings are consistent with physicians’ stated reasons for switching versus augmenting antipsychotics in the treatment of schizophrenia. Confirmation of these findings requires further research.

Keywords: augmentation, drug substitution, polypharmacy, schizophrenia, switching