Effect of an Institutional Medication Adherence Program for Long-Acting Injectable Risperidone on Adherence and Psychiatric Hospitalizations: Evidence from a Prospective Cohort Study

Background: Long-acting injectable (LAI) atypical antipsychotics are associated with improved adherence and reduced relapse rates in schizophrenia but reminder-based interventions may further improve outcomes.

Objectives: To assess an institutional medication adherence program's (IMAP) effectiveness on adherence and psychiatric hospitalizations among schizophrenia patients taking risperidone LAI (RLAI).

Methods: Between 2009 and 2010, we recruited patients meeting DSM-IV criteria for schizophrenia treated with RLAI receiving outpatient care from psychiatric centres in France. The IMAP consisted of calling patients 48 hours prior to their scheduled RLAI injections and within 3 days of a missed appointment. Centres applying the IMAP to ≥50% of scheduled patient injections were deemed compliant. Patients were followed up to one year for adherence (≥80% of scheduled RLAI injections received within 5 days of the scheduled date) and psychiatric hospitalizations.

Results: Among 506 patients recruited from 36 centres, the hospitalization rate was 32.5 per 100 person-years. 15 centres treating 243 patients were IMAP compliant and 21 centres treating 263 patients were not. IMAP compliance was associated with lower psychiatric hospitalization rates (crude RR: 0.64 [95% CI: 0.44-0.93]; adjusted RR: 0.78 [95% CI: 0.47-1.27]). Nearly 75% of patients were adherent to RLAI. While patient adherence had little impact on hospitalization rates (adjusted RR: 0.92 [95% CI: 0.59-1.44]), IMAP compliance was more effective among non-adherent (adjusted RR: 0.45 [95% CI: 0.16-1.28]) than adherent (adjusted RR: 0.88 [95% CI: 0.51-1.53]) patients.

Conclusions: IMAPs may improve patient adherence and reduce psychiatric hospitalizations, particularly among patients with difficulties adhering to LAI antipsychotics.