Prescribing factors influencing hospital length of stay in patients initiating lithium therapy for acute bipolar or schizoaffective mood episodes

Abstract Introduction Lithium has long been considered the gold standard mood stabilizer in the treatment of acute mood episodes related to bipolar (BD) and schizoaffective disorder. Previous research has primarily focused on lithium loading strategies and their effects on symptom severity and inpatient length of stay (LOS). However, less is known about specific prescribing practices at lithium initiation that may influence LOS. Methods This retrospective study aimed to evaluate three initiation-related prescribing factors of lithium and their association with changes in LOS among adult inpatients experiencing acute mood episodes of BD or schizoaffective disorder. The factors were lithium initiation within 48 hours of admission, achieving a therapeutic level-producing dose within 48 hours of admission, and receiving intensive initial lithium dosing (≥900 mg/day). The Mann-Whitney U test was used to assess statistical significance. The timing of antipsychotic coprescribing in mania was also evaluated. Results Sixty-eight patients were included in this study. Lithium initiation within 48 hours of admission significantly decreased hospital LOS (7.2 vs 13.4 days; P < 0.001). Lithium optimization to a dose that produced a therapeutic drug level within 48 hours of admission also significantly decreased LOS (6.2 vs 9.1 days; P < 0.01). Intensive initial dosing did not significantly affect LOS. Of patients with mania, 51.5% were trialed on antipsychotics before starting lithium. Conclusion Early lithium initiation and optimization in patients with acute bipolar mood episodes significantly reduced hospital LOS. Prospective studies are needed to address potential confounders to confirm whether early lithium optimization directly reduces LOS.