Discharge Delays and Costs Associated with Outpatient Parenteral Antimicrobial Therapy for High priced Antibiotics.

BACKGROUND Outpatient parenteral antimicrobial therapy (OPAT) is a widely-used safe and cost-effective treatment strategies. Most public and private insurance providers require prior authorization (PA) for OPAT, yet impact of the inpatient PA process is not known. This study aimed to characterize discharge barriers and PA delays associated with high-priced OPAT antibiotics. METHODS IRB-approved study of adult patients discharged with high-priced OPAT antibiotics from January to December 2017. Antibiotics included: daptomycin, ceftaroline, ertapenem, and the novel beta-lactam beta-lactam inhibitor combinations. Patients with an OPAT PA delay were compared to patients without. Primary endpoint: total direct hospital costs from the start of treatment. Secondary outcomes: discharge delay and 30-day readmission or mortality. RESULTS Two-hundred patients included: 141 (71%) no OPAT delay vs 59 (30%) OPAT delay. More patients with a PA delay were discharged to a sub-acute care facility compared to an outpatient setting: 37 (63%) vs 52 (37%), p=0.001. Discharge delays and median total direct hospital costs were higher in patients with OPAT delays: 31 (53%) vs 21 (15%), p<0.001; and $19,576 vs (IQR 10,056-37,038) vs $7,770 (IQR 3,031-13,974), p<0.001. In a multiple variable regression, discharge to a sub-acute care facility was associated with an increased odds of discharge delay while age over 64 years was associated with a decreased odds of discharge delay. CONCLUSIONS OPAT with high-priced antibiotics requires significant care coordination. PA delays for these antibiotics are common and contribute to discharge delays. OPAT transitions of care represent an opportunity to improve patient are and address access barriers.