From QAAPAPLE 1 to QAAPAPLE 2: how do we move from one algorithm to another one with Long Acting Antipsychotics (LAIs)

Comparative effectiveness and safety of antipsychotic drugs in patients with schizophrenia initiating or reinitiating treatment: A Real-World Observational Study

OBJECTIVE

To compare the effectiveness and safety of various second-generation antipsychotics (SGAs), newer oral and long-acting injectable (LAI) SGAs, and first-generation antipsychotics (FGAs) treatments in patients with schizophrenia or schizoaffective disorder (SCZ).

METHODS

This retrospective cohort study included medical administrative information for patients with a diagnosis of SCZ living in Quebec (Canada), initiating or reinitiating at least one antipsychotic (AP) drug (with a clearance baseline period of 12 months without any APs). Effectiveness was defined by a reduced risk of hospitalization for mental disorder and discontinuation, and safety by a reduced risk of all-cause death and hospitalization for non-mental disorder, 2 years after AP initiation or reinitiation. Cox proportional hazard models were used to estimate the events associated with different antipsychotics compared with oral olanzapine.

RESULTS

The study cohort included 19,615 patients initiating or reinitiating an antipsychotic drug between January 2006 and December 2015. Results showed better effectiveness of clozapine (adjusted HR 0.36, 95% CI 0.30-0.42, p < 0.0001) and LAI SGAs (adjusted HR 0.56, 95% CI 0.51-0.61, p < 0.0001) compared with oral olanzapine when adding discontinuation to hospitalizations for mental disorder as a composite measure of effectiveness, as opposed to oral FGAs (adjusted HR 1.36, 95% CI 1.27-1.46, p < 0.0001) and LAI FGAs (adjusted HR 1.22, 95% CI 1.12-1.32, p < 0.0001). Most APs were as safe as oral olanzapine.

CONCLUSION

The effectiveness of LAI SGAs and clozapine appears to justify their use and are as safe as a recognized treatment (oral olanzapine) in Quebec (Canada).

Antipsychotic utilization trajectories three years after initiating or reinitiating treatment of schizophrenia: A state sequence analysis approach

OBJECTIVE

This study aims to describe the utilization patterns of antipsychotic (AP) medication in patients with schizophrenia (SCZ), three years after initiating or reinitiating a given AP.

METHODS

Based on medico-administrative information on patients living in Quebec (Canada), this retrospective cohort study included 6444 patients with a previous diagnosis of SCZ initiating or reinitiating AP medication between January 1, 2012, and December 31, 2014, with continuous coverage by public drug insurance. For each day of follow-up (1092 days), patient was either exposed to one of the chosen categories of APs, or to none. This patient's sequence of AP exposure overtime has been referred to as the "antipsychotic utilization trajectory". These trajectories were analyzed using a State Sequence Analysis, an innovative approach which provides useful visual information on the continuation and discontinuation patterns of use over time.

RESULTS

Clozapine and long-acting injectable second-generation APs had the best continuation and discontinuation patterns over 3 years among all other groups, including less switching of APs, while oral first-generation APs had the poorest patterns. These findings were comparable among incident and non-incident cohorts. Oral second-generation antipsychotics, excluding clozapine, had a poorer continuation and discontinuation pattern than long-acting injectable antipsychotics.

CONCLUSION

State Sequence Analysis provides a clear representation of treatment adherence in comparison with dichotomous indicators of adherence or discontinuation. Consequently, this innovative method has shed light on the impact of the AP chosen to initiate or reinitiate treatment in SCZ, which has been identified as a key factor for long-term treatment continuation and discontinuation.