Thirty-five months experience of risperidone long-acting injection in a UK psychiatric service including a mirror-image analysis of in-patient care

Objective: To report the use of risperidone long-acting injection (RLAI) in a UK psychiatric service. Method: Retrospective case note review of all patients prescribed RLAI over a 35-month period. In the mirror-image analysis patients initiated on RLAI as in-patients had the index admission attributed to previous treatment. Results: Patients prescribed RLAI had significantly higher baseline rates of drug misuse, alcohol misuse, unemployment and forensic markers than control patients prescribed oral antipsychotics. Most patients started RLAI because of poor compliance with oral antipsychotics. Inefficacy accounted for more discontinuations than intolerability. Fifty-eight percent (39/67) of patients were continuing RLAI 12 months after initiation. Mirror-image analysis (n = 74) showed that RLAI was associated with a reduction in the number of admissions (65 vs. 33, P < 0.005) and in total in-patient days (4550 vs. 2188 days, P < 0.005). The mean reduction in in-patient care was 29 days per patient-year of treatment, equivalent to a net financial saving over the acquisition and administration costs of RLAI of 1172 pound. Conclusion: Risperidone long-acting injection was associated with reduced in-patient care and was cost-effective.