Changes in compliance with Japanese antiemetic guideline for chemotherapy-induced nausea and vomiting: a nationwide survey using a distributed research network

Abstract

Prophylaxis of chemotherapy (CT)-induced nausea and vomiting (CINV) is important for patient's quality of life and adherence to CT. Neurokinin receptor antagonist (NK1 antagonist) was marketed in Japan in December 2009 and the first guideline for antiemetics for CINV was released in May 2010 from Japan Society of Clinical Oncology (JSCO). We assessed changes in compliance with the JSCO guideline during the first 18 months from the launch of NK1 antagonist in Japan. Patient-level data was extracted locally using a nationwide distributed research network consisting of 39 hospitals. Monthly compliance rates for acute (day of CT) and delayed (days 2-5) phases were summarized according to the emetic risks. In total, 81,739 CTs for 9,978 patients were analyzed. Prescription of oral NK1 antagonist was started in 31/39 hospitals during the study period. The compliance in acute phase for high emetic risk (HER) CTs gradually improved up to 39.3% whereas it reached only to 10-15% in delayed phase. The extra use of antiemetics decreased inversely to the increased compliance. Better compliance for HER CTs was associated with opioid use, younger age, second or later cycles, and CT regimens. Compliance in acute phase was better in inpatient whereas that in delayed phase was better in outpatients. A multi-hospital survey revealed that more than half of the HER CTs remained without accompanying the standard antiemetic therapies. Association with the compliance and CINV outcomes would be also interesting to explore.