Early prediction of clinical response in first episode schizophrenia (FES) patients receiving olanzapine

Abstract

Background: At present, schizophrenia guidelines recommend waiting for 8 weeks before considering a patient as non-responder. This study aims to detect the optimal early response threshold that best predict the final outcome of olanzapine.

Methods: The study was conducted for 8-week, four points follow up (week 2,3,4, and 8) prospective observational study. A reduction of 20, 25, 30% in Positive and Negative Syndrome Scale (PANSS) score from the base line at week 2,3, and 4 respectively were considered as early response. A reduction of 50% at week 8 was considered as responders. Receiver Operating Characteristics (ROC) curves were performed to detect the optimal threshold.

Results: Mean total baseline PANSS score was 106.66(95% CI; 100.4, 112.9). Week 2 (AUC = 50.5%, p > 0.964) and week 3 (AUC = 64.9, p > 0.13) responses failed to predict the 8th week response. Week 4 response (AUC = 92%, p < 0.001) can be taken for the prediction of 8th week response (specificity = 72%, sensitivity = 100%, Positive Predictive Value = 61.1%, Negative Predictive Value = 100% and Optimum Early Response (OER) = 29.4%). 25 patients (69%) achieved more than 50% reduction (responders) in PANSS score after 8 weeks of treatment.

Conclusions: Our study suggests that patients with early response at week 4 are likely to achieve positive response after 8 weeks. This may help in appropriate clinical decision making for early non-responders.

Key Points

• The early response can forecast the outcome at the endpoint for the treatment of FES

• A reduction of baseline PANSS score by 30% or more after four weeks are likely to have remission after week 8 with olanzapine therapy.

Keywords:

• Schizophrenia
• early response
• olanzapine
• PANSS

Acknowledgement

The authors thank our Dean & Professors, Faculty of Pharmacy, M S Ramaiah University of Applied Sciences who provided insight and expertise that greatly assisted the research. We thank Mrs. Radhika, Bio-statistician, Ramaiah Medical College for assistance with statistical analysis that greatly improved the manuscript.

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

This research work hasn’t received any kind of financial support.