Clinical outcomes of long-acting injectable risperidone in patients with bipolar I disorder: A 1-year retrospective cohort study

•Risperidone long-acting injection is prescribed for severe bipolar I patients.•Risperidone LAI significantly lowers rehospitalization rate of bipolar I patients.•Risperidone LAI significantly lowers emergency visit of bipolar I disorder patients.•Risperidone LAI reduces manic and depression severity in bipolar I disorder patients.

ObjectivesWe explored the effect of risperidone long-acting injection (LAI) treatment on patients with bipolar I disorder in a real-world setting.MethodsIn this retrospective cohort study, 469 patients with bipolar I disorder were enrolled and treated with risperidone LAI and different oral antipsychotics and followed for 1 year. Concomitant medications, such as mood stabilizers, antidepressant, anxiolytics, hypnotics, or anticholinergics, were administered. On the basis of risperidone LAI use and treatment compliance, the patients were classified into 4 groups: the first long-acting injectable antipsychotics (LAI1) group (compliant patients receiving risperidone LAI treatment) (N=44), the second long-acting injectable antipsychotics (LAI2) group (non-compliant patients receiving risperidone LAI treatment) (N=33), the first non-LAI (NLAI1) group (compliant patients receiving oral medications) (N =337), and the second non-LAI (NLAI2) group (non-compliant patients receiving oral medications) (N=55). The rate of re-hospitalization, length of hospital stay, and rate of emergency room visit were assessed.ResultsCompared with the non-LAI groups, the LAI groups had longer mean duration of illness (8.5 years, P=0.0001), higher rate of admission due to mood episodes (P<0.0001), depressive episodes (P<0.0001), or manic episodes (P=0.0002), and higher rate of emergency room visit (P=0.0003) before enrollment. After a 1-year follow-up, re-hospitalization rates were significantly lower in the LAI1 group than that before enrollment for any episodes (P=0.0001), manic episodes (P=0.005), and depressive episodes (P=0.002). The rates of emergency room visit were significantly lower in the LAI1 (P=0.0001), LAI2 (P=0.013), and NLAI1 (P=0.0001) groups compared with those before enrollment.ConclusionsRisperidone LAI reduces the clinical severity of bipolar I disorder.