Incidence of chemotherapy-induced nausea and vomiting in Mexico: healthcare provider predictions versus observed.

OBJECTIVE: An understanding of the incidence of chemotherapy-induced nausea and vomiting (CINV) may assist healthcare providers (HCP) when making treatment decisions. We investigated the incidence of CINV after highly or moderately emetogenic chemotherapy (HEC or MEC), in comparison with predictions of CINV by HCP.

RESEARCH DESIGN AND METHODS: This prospective study was conducted at nine oncology centers in Mexico. Eligible patients were >/=18 years old and scheduled to receive a single, initial cycle of chemotherapy. Patients recorded nausea severity, episodes of emesis, and rescue medication use for the first 5 days after chemotherapy. HCP predicted the general incidence of acute (day 1) and delayed (days 2-5) CINV.

RESULTS: A total of 82 patients were enrolled, with complete data available for 73. Mean age was 50 years; 67 (92%) were women; and 57 (78%) received HEC, while 16 (22%) received MEC. HCP predictions were comparable to the incidence of acute CINV after HEC and MEC and of delayed CINV after MEC. However, HCP predictions underestimated delayed CINV after HEC. 75.4% of patients (95% CI: 62.2-85.9) reported delayed nausea and HCP predicted 41.7% (95% CI: 30.2-55.0); 63.2% of patients (95% CI: 49.3-75.6) reported delayed emesis and HCP predicted 31.8% (95% CI: 21.0-44.5). Limitations of the study include the small sample size, possible selection bias and lack of a standardized antiemetic regimen.

CONCLUSIONS: Healthcare providers underestimated the incidence of delayed CINV after HEC. There is a need for a better understanding of the incidence of delayed nausea and emesis, which remain common side-effects of chemotherapy.