Psychological factors predicting nausea and vomiting in breast cancer patients on chemotherapy

A series of 100 breast cancer patients were included in a study to test the hypothesis that incidence of anticipatory nausea and vomiting during chemotherapy and towards the end of a patient's course of treatment is influenced by patient expectation, anxiety level and coping response. The role of psychological factors in postinfusional nausea and vomiting was also examined. Incidence of postinfusional and anticipatory nausea was high overall, with vomiting less frequently reported; 43% of patients reported nausea or vomiting before treatment at some stage over their chemotherapy cycles and 77% reported post-treatment symptoms. Anticipatory nausea was described by 47% of those experiencing it as being of moderate or severe intensity at some point throughout chemotherapy. Postinfusional side-effects were more intense; 21 and 10 patients, respectively, described severe or very severe levels as occurring at some point during their treatment. The majority of patients experiencing postinfusional symptoms indicated that these persisted for more than 24 h and were worse a day or two after chemotherapy administration. Incidence of anticipatory nausea or vomiting was found to relate directly to experience of nausea or vomiting during preceding cycles. Psychological variables were associated with symptoms of anticipatory nausea mid-treatment, but not with postinfusional symptoms. In particular, trait anxiety and a baseline expectation that nausea would be experienced during treatment were predictive in a multivariate model. Despite this, the overwhelming factor influencing ANV and PNV both mid- and towards the end of treatment was that of previous experience of the symptoms at earlier courses.