Impact of rifaximin use following an initial overt hepatic encephalopathy hospitalization on rehospitalization and costs.

Aim: To assess the impact of rifaximin (± lactulose) use following discharge of an initial overt hepatic encephalopathy (OHE) hospitalization on OHE rehospitalizations and healthcare costs in a real-world setting.

Methods: Adults (18-64 years) with an OHE hospitalization were identified from MarketScan® Commercial claims (Q4'15-Q2'20), classified into two mutually exclusive treatment cohorts (i.e. rifaximin and no rifaximin treatment), and further stratified into four subgroups based on decreasing quality of care (QoC; i.e. Type 1 - rifaximin without delay post-discharge; Type 2 - rifaximin with delay post-discharge; Type 3 - lactulose only post-discharge; Type 4 - no rifaximin/lactulose treatment post-discharge). The impact of rifaximin use on 30-day and annualized OHE hospitalizations and healthcare costs were assessed between cohorts and by the QoC subgroup.

Results: Characteristics were similar between the rifaximin ( = 1,452; Type 1: 1,138, Type 2: 314) and no rifaximin ( = 560; Type 3:337, Type 4: 223) treatment cohorts. The 30-day risk of OHE rehospitalization was lower for the rifaximin vs. no rifaximin treatment cohort (odds ratio 0.56,  < .01) and increased with decreasing QoC. The annual rate of OHE hospitalizations was 59% lower for the rifaximin treatment cohort (incidence rate ratio 0.41,  < .01) and increased with decreasing QoC. Compared to the no rifaximin treatment cohort, the rifaximin treatment cohort had higher pharmacy costs, lower medical costs, and no difference in total healthcare costs.

Limitations: This was a claims-based study subject to common data limitations such as billing inaccuracies or omissions in coded claims. Total healthcare costs were reported from a payer's perspective, which do not capture indirect costs associated with patient burden.

Conclusions: Initiation of rifaximin after an OHE hospitalization was associated with reduced OHE hospitalizations both in the 30-days following and annually. Further, reduced medical costs offset increased pharmacy costs, and no annual cost differences were observed between cohorts.