Clinical and economic burden of chemotherapy-induced nausea and vomiting among patients with cancer in a hospital outpatient setting in the United States.

OBJECTIVE: This study evaluated the overall burden of illness of chemotherapy-induced nausea and vomiting (CINV) and associated all-cause costs from a hospital's perspective (costs to the hospital) in patients with cancer treated with chemotherapy (CT) in the US hospital outpatient setting.
METHODS: Patients with a cancer diagnosis aged ≥18 years initiating CT in a hospital outpatient setting for the first time between April 1 2007 and March 31 2009 were extracted from the Premier Perspective Database. Patients were followed through eight CT cycles or 6 months post-index date, whichever occurred first. Within each CT cycle, the follow-up time for CINV event estimation was from day 1 (except rescue medication use that was identified from day 2) to cycle end. A multivariate regression model was developed to predict the CINV event rate per CT cycle in the study follow-up period. Associated total all-cause costs of managing CINV from a hospital's perspective were analyzed descriptively. Event rate and associated costs were estimated in the entire hospital setting (outpatient, inpatient, and emergency room). All-cause costs included inpatient, hospital outpatient, and ER visit costs (identified through a primary or secondary diagnosis code for nausea, vomiting, and/or volume depletion) and pharmacy cost (rescue medications for CINV treatment). All physician costs and non CINV-related treatment (pharmacy) costs were excluded from the analyses.
RESULTS: Among 11,495 study patients, 8,806 patients (76.6%) received prophylaxis for all cycles in the follow-up period. The overall base population had an average age of 63.3 years, was 51.0% female, and 72.7% White. The distribution of emetogenicity for cycle 1 CT cycle was 26.0% HEC, 46.1% MEC, and 26.4% LEC/MinEC combined. In the follow-up period, a total of 47,988 CINV events with an associated total all-cause treatment cost of $89 million were observed. Average daily treatment cost for all care settings was $1854.7. The regression model predicted a 20% CINV event rate per CT cycle in the follow-up period. Study limitations include potential lack of generalizibility, absence of data on certain confounders including alcohol consumption and prior history of motion sickness, lack of a control analysis group to estimate incremental use of resource utilization and associated costs, and a potential for cost under-estimation.
CONCLUSION: In the current study analysis, a 20% CINV event rate per CT cycle per patient was predicted with an associated all-cause average daily total cost of approximately $1850. Further studies on early and appropriate antiemetic prophylaxis on CINV rates and economic outcomes are warranted.