Friday, July 11, 2008
Patient expectations & nausea
Cancer has a paper about patient expectations and how they relate to chemotherapy related nausea. The data come from a multi-center trial comparing several anti-nausea regimens. This analysis looked at ~670 first-time chemotherapy patients who were all asked at baseline how likely they thought they'd have nausea, and how severe they thought it would be. After chemotherapy patients kept a nausea log (per the treatment trial protocol). Patients who were most expectant of severe nausea did, in fact, have worse nausea (worse average and worse peak nausea) than the other patients (those who had no nausea or a 'moderate' expectation of nausea had similar rates). Vomiting was not measured as far as I can tell.
A few thoughts about this.... It's possible from this study that patients who expected the worst were also more likely to give higher nausea scores than patients who didn't (that is - they were more likely to give higher nausea scores no matter what due to some underlying characteristic - this is akin to acknowledging that one group's 7/10 pain may be different from a 2nd group's 7/10 pain). I'm not sure you could get around this by measuring vomiting although it would have been interesting if nausea scores were different but vomiting episodes were the same. Not that nausea alone isn't dreadful. One interpretation here of course is that expectation indeed does correlate with symptoms. If this is so, you could argue that clinicians should therapeutically minimize the possibility of nausea when discussing chemo with patients. A similar approach has been proposed with procedural pain: I can't remember the reference but there have been findings that the more clinicians say things like 'this is going to hurt....' the more patients, in fact, hurt. Shutting up during procedures has been proposed as a superior technique based on these findings.