Purpose: To evaluate the effectiveness of the Information Technology-Aided Program of Re lapse Prevention in Schizophrenia (ITAREPS).
Methods: Relapse-prone outpatients with schizophrenia or schizoaffective disorder were randomized to the active (n=75) or control group (n=71). In the active arm, according to the protocol, investigators were prompted to increase the antipsychotic dose upon occurrence of a pharmacological inter vention requiring event (PIRE) detected by ITAREPS.
Results: Intention-to-treat (ITT) analysis found no between-group difference in the hospitalization-free survival rate at 12 months. However, the trial suffered from high non-adherence of investigators in the active group, with no antipsychotic dose increase in 61% of PIREs. Furthermore, Cox regression analysis showed a 11-fold increased risk of hospitalization in the absence of pharmacological intervention following a PIRE (hazard ratio [HR]=10.8; 95% confidence interval [CI] 1.4-80.0; p=0.002). Therefore, a post-hoc as-treated analysis was performed, which demonstrated a nine-fold reduction in the risk of hospitalization in ITAREPS Algorithm-Adherers (IAAs, n=25) compared with the ITAREPS Non-interventional group (INIs, n=70; Kaplan-Meier survival analysis, HR=0.11, 95% CI 0.05-0.28, p=0.009; number needed to treat [NNT]=4, 95% CI 3-10). A significant difference in favor of the IAA group was seen in the number of inpatient days (p<0.05) and costs (p<0.05).
Conclusion: Future ITAREPS trials should target the underlying mechanisms that cause low investigator adherence to the program.
Trial registration: Clinical Trials NCT00712660.