Treatment Retention with Risperidone Long-acting Injection: 24-month Results from the Electronic Schizophrenia Treatment Adherence Registry (e-STAR) in Six Countries

Objective: To assess treatment retention on risperidone long-acting injection (RLAI) and outcomes in schizophrenia patients for whom 24 months of follow-up data in the electronic Schizophrenia Treatment Adherence Registry (e-STAR) were available.

Research Design And Methods: e-STAR is an ongoing, international, multicenter, prospective, observational registry assessing use of antipsychotics in patients with schizophrenia or schizoaffective disorder in a normal clinical practice setting. Parameters were assessed prior to and post-initiation of RLAI. Data presented are from six European countries that enrolled patients in e-STAR after they initiated treatment with RLAI.

Main Outcome Measures: Clinical and demographic information were collected at baseline and treatment-related data, including RLAI discontinuation, psychiatric hospitalization and medication utilization, were collected prospectively every 3 months. Data collection continued for 24 months, even for patients who discontinued RLAI therapy. Hospitalization and medication utilization were also collected retrospectively by chart review for the 12-month period prior to RLAI initiation.

Results: A total of 1659 patients (mean age, 39.2; 18.3% inpatients) completed the study. Twenty-four months after initiating therapy (initial RLAI dose = 33.6 mg) 85% of patients (n = 1410) remained on RLAI (completers) while 15% discontinued therapy. The main reasons for discontinuation were insufficient response (28.5%), patient/family choice (26.1%), adverse events (9.6%) and unacceptable tolerability (6.0%). At baseline, compared to completers, discontinuers were younger (37.4 vs. 39.6 years, p = 0.01), had schizophrenia for a shorter time (10.2 vs. 11.9 years, p = 0.02), had lower Global Assessment of Functioning (GAF) scores (43.5 vs. 48.0, p = 0.0001), higher utilization of benzodiazepines (56.5 vs. 43.3%) and more initiated therapy as inpatients (30 vs. 16%). With RLAI therapy GAF scores improved significantly (p < 0.001) for both groups but the 24-month value for discontinuers was lower than that of completers (55.4 vs. 67.2). Compared to the pre-RLAI initiation period, at 12 months post-initiation completers had greater reductions than discontinuers in the percent of patients hospitalized (66.2% reduction vs. 29.2%) and in the length (68% reduction vs. 0%) and number (80.0 vs. 14.3%) of hospital stays, differences that remained at 24 months. The most common adverse events while patients were taking RLAI were nervous system disorders (6.8%), psychiatric disorders (5.6%), weight increase (3.2%), reproductive system and breast disorders (2.5%) and gastrointestinal disorders (2.1%).

Conclusions: These observational data confirm that RLAI is an effective treatment in schizophrenia and high levels of adherence to therapy offers an opportunity for effective long-term disease management and significant sustained decreases in hospitalization.