A retrospective analysis of inpatient utilization of paliperidone palmitate

Purpose: This study evaluated pharmacoeconomic considerations, specifically drug cost and patient readmission rates, of the non-formulary agent paliperidone palmitate, within the Alegent Health system.  Pharmacy reimbursement rates for paliperidone palmitate are better on an outpatient versus inpatient basis.  Given the low reimbursement rates for inpatient psychiatric care and the high cost of paliperidone palmitate, the drug cost could be justified if patients who received the injection demonstrated a subsequent reduction in readmission. 

Methods: Thirty two patients have received at least one inpatient injection of paliperidone palmitate within the Alegent Health system from January 2010 – April 2012.  The electronic medical record was used to determine indication, dose, administration date, concurrent antipsychotics, length of stay (LOS), and time to readmission.  Finance reports determined hospital cost and reimbursement for each inpatient stay and pharmacy cost of each paliperidone palmitate injection. 

Results: The readmission rates for the paliperidone palmitate patients vs all patients at our institution with a drug related group (DRG) of psychoses were as follows: within 30 days, 22% vs 12.5%; 60 days, 15% vs 15%; and 90 days, 25% vs 18%, respectively.  The hospital experienced a net loss of roughly $5,610 per stay for the patients studied and paliperidone palmitate constituted approximately 15.9% of total hospital cost per stay. The average LOS was 18 days.

Conclusion: In this limited patient population, it appears inpatient administration of paliperidone palmitate increased hospital cost without significantly reducing readmission rates at 30, 60, or 90 days post-injection.  If patients are due for their monthly maintenance dose while institutionalized, the injection should be deferred to outpatient if discharge is anticipated within one week since product labeling states maintenance injections can be given 7 days after the monthly due date and outpatient reimbursement for the drug is superior.