Treatment effectiveness and adherence in patients with schizophrenia treated with risperidone long-acting injection.

This study investigated the variables related to the effectiveness and adherence to treatment with risperidone long-acting injection (RLAI) in patients with schizophrenia. We performed a retrospective medical chart review of 137 patients with schizophrenia who were prescribed RLAI between July 2004 and December 2006. Cox regression analysis showed that the effectiveness of treatment in patients treated with RLAI was affected significantly by the provision of home care and the use of illicit drugs. The adherence of patients to treatment with RLAI was affected most by the provision of home care. Bayesian analysis showed that patients who received the provision of home care or who had no history of illicit drug use continued treatment for, on average, 15.27 and 17.14days longer, respectively, than those who did not receive such care or take illicit drugs. Patients who received the provision of home care adhered to treatment for 343.98 more days than those who did not. Even though patients taking RLAI show better adherence than those taking oral risperidone, home care services can have a significant additional effect on adherence. Randomized clinical follow-up trial studies are necessary to explore the risk factors for nonadherence in more detail.