Preventive effect of aripiprazole once monthly on rehospitalization for bipolar disorder: A multicenter 1‐year retrospective mirror image study

Aim We conducted a 1‐year retrospective mirror‐image study to investigate the effect of aripiprazole once monthly (AOM) on rehospitalization for bipolar disorder. Methods Participants were recruited from psychiatric emergency and acute care hospitals in western Japan. We included 39 participants with bipolar disorder who had been administered AOM for at least 1 year with no missing medical records during the observational period. The primary outcomes were rehospitalization rate, number of rehospitalizations, total hospitalization days, and time to rehospitalization in the context of overall psychiatric readmissions. The significance level was set at p