Incidence and predictors of anticipatory nausea and vomiting in Asia Pacific clinical practice--a longitudinal analysis.

PURPOSE: Some patients experience nausea and/or vomiting (NV) before receipt of chemotherapy. Our objective was to evaluate the impact of prior chemotherapy-induced NV (CINV) on the incidence of anticipatory NV in later cycles.
METHODS: This multicenter, prospective non-interventional study enrolled chemotherapy-naïve adults scheduled to receive highly or moderately emetogenic chemotherapy (HEC/MEC) for cancer in six Asia Pacific countries, excluding those with emesis within 24 h before cycle 1 chemotherapy. On day 1 before chemotherapy, patients answered four questions regarding emesis in the past 24 h, nausea, expectation of post-chemotherapy nausea, and anxiety in the past 24 h, the latter three scored from 0-10 (none-maximum). Multivariate logistic regression was used to assess the impact of prior CINV on anticipatory NV in cycles 2 and 3.
RESULTS: Five hundred ninety-eight patients (59% female) were evaluable in cycle 2 (49% HEC, 51% MEC). The incidence of anticipatory emesis was low before cycles 2 and 3 (1.5-2.3%). The incidence of clinically significant anticipatory nausea (score of ≥3) was 4.8, 7.9, and 8.3% before cycles 1, 2, and 3, respectively, with adjusted odds ratio (OR), 3.95 (95% confidence interval (CI), 2.23-7.00; p < 0.001) for patients with clinically significant nausea in prior cycles, compared with none. The adjusted ORs for other anticipatory NV endpoints ranged from 4.54-4.74 for patients with prior CINV. The occurrence of clinically significant anxiety in the prior cycle also resulted in a significantly increased likelihood of anticipatory nausea.
CONCLUSIONS: These findings highlight the importance of preventing CINV in cycle 1 to reduce anticipatory NV in subsequent cycles.