Specific response expectancies predict anticipatory nausea during chemotherapy for breast cancer.

Clinical research has demonstrated that large numbers of chemotherapy patients continue to experience nausea in the clinic prior to infusions. A better understanding of the mechanisms responsible for such anticipatory nausea (AN) is likely to provide critical information for identifying intervention targets. In the present study the authors investigated the contribution of expectancy, history of nausea, and distress to AN in 60 women with Stage I or II breast cancer receiving standard adjuvant chemotherapy. The predictors were each independently associated with AN (p < .05). However, only expectations significantly predicted AN in simultaneous regression analyses. Results suggest that interventions to reduce AN during chemotherapy should target patients' expectations.

Behavioral intervention for cancer treatment side effects.

The use of increasingly aggressive methods of cancer treatment during the last 20 years has brought clinical attention to the need for more effective management of pain, nausea, and other aversive side effects of state-of-the-art cancer therapy. One of the most promising approaches to effective management is nonpharmacologic intervention based on behavioral research and theory. The purpose of this review is to examine the effectiveness of behavioral intervention methods in the control of aversive side effects of cancer treatments. Fifty-four published studies using a variety of research designs were identified for review. Results indicated the following: 1) Behavioral intervention can effectively control anticipatory nausea and vomiting in adult and pediatric cancer patients undergoing chemotherapy; however, the evidence for the efficacy of behavioral intervention to control post-chemotherapy nausea and vomiting is less clear. 2) Behavioral intervention integrating several behavioral methods can ameliorate anxiety and distress associated with invasive medical treatments. 3) Although a variety of behavioral methods have been shown to reduce acute treatment-related pain, there is increasing evidence that these methods are not equally effective. Hypnotic-like methods, involving relaxation, suggestion, and distracting imagery, hold the greatest promise for pain management. Unfortunately, research is scant on the use of behavioral intervention to control prolonged pain associated with invasive medical procedures. It is clear that the application of behavioral theory and methods has an important place in the care of patients undergoing invasive cancer treatments.

A meta-analysis of hypnotically induced analgesia: how effective is hypnosis?

Over the past two decades, hypnoanalgesia has been widely studied; however, no systematic attempts have been made to determine the average size of hypnoanalgesic effects or establish the generalizability of these effects from the laboratory to the clinic. This study examines the effectiveness of hypnosis in pain management, compares studies that evaluated hypnotic pain reduction in healthy volunteers vs. those using patient samples, compares hypnoanalgesic effects and participants' hypnotic suggestibility, and determines the effectiveness of hypnotic suggestion for pain relief relative to other nonhypnotic psychological interventions. Meta-analysis of 18 studies revealed a moderate to large hypnoanalgesic effect, supporting the efficacy of hypnotic techniques for pain management. The results also indicated that hypnotic suggestion was equally effective in reducing both clinical and experimental pain. The overall results suggest broader application of hypnoanalgesic techniques with pain patients.

It won't happen to me: lower perception of heart disease risk among women with family histories of breast cancer.

BACKGROUND: The threat that breast cancer poses to American women, particularly to women with family histories of the disease, has received widespread attention in both medical and popular literatures. While this emphasis may have laudable consequences on breast cancer screening, it may also have a negative consequence, obscuring women's recognition of their risks for other health threats, such as heart disease. This study examined the possibility that women with family histories of breast cancer may be particularly susceptible to overestimating their risks of breast cancer while minimizing their risks of cardiovascular disease. METHODS: Healthy women with (n = 73) and without n = 104) family histories of breast cancer (64% African American, 26% Caucasian, 10% other ethnicities, mean age 41.7 years) were recruited from medical centers in New York City, and completed questionnaires concerning their family histories and perceptions of risk. RESULTS: Consistent with the study hypothesis, women with family histories of breast cancer had significantly higher perceived lifetime risk of breast cancer (P<0.0002) but lower perceived lifetime risk of heart disease (P<0.002) than women without family histories. Additionally, women with family histories of breast cancer had lower perceived colon cancer risk (P<0.02), suggesting that women with family histories of breast cancer may be underestimating their risks for a variety of diseases. CONCLUSION: The emphasis on breast cancer risk, especially for women with family histories of the disease, may need to be balanced by educational efforts concerning women's risk of other diseases, particularly cardiovascular disease.

An analysis of factors that contribute to the magnitude of placebo analgesia in an experimental paradigm.

Placebo analgesia was produced by conditioning trials wherein heat induced experimental pain was surreptitiously reduced in order to test psychological factors of expectancy and desire for pain reduction as possible mediators of placebo analgesia. The magnitudes of placebo effects were assessed after these conditioning trials and during trials wherein stimulus intensities were reestablished to original baseline levels. In addition, analyses were made of the influence of these psychological factors on concurrently assessed pain and remembered pain intensities. Statistically reliable placebo effects on sensory and affective measures of pain were graded according to the extent of surreptitious lowering of stimulus strength during the manipulation trials, consistent with conditioning. However, all of these effects were strongly associated with expectancy but not desire for relief. These results show that although conditioning may be sufficient for placebo analgesia, it is likely to be mediated by expectancy. The results further demonstrated that placebo effects based on remembered pain were 3 to 4 times greater than those based on concurrently assessed placebo effects, primarily because baseline pain was remembered as being much more intense than it actually was. However, similar to concurrent placebo effects, remembered placebo effects were strongly associated with expected pain levels that occurred just after conditioning. Taken together, these results suggest that magnitudes of placebo effect are dependent on multiple factors, including conditioning, expectancy, and whether analgesia is assessed concurrently or retrospectively.

Surreptitious observation of responses to hypnotically suggested hallucinations: a test of the compliance hypothesis.

Suggestions for arm levitation and for visual, auditory, tactile, and taste hallucinations were administered twice via audiotape to a group of high suggestible students and low suggestible simulators. During one of the administrations, participants were led to believe they were alone, but their behavior was surreptitiously recorded on videotape and observed on a video monitor. During the other administration, they were observed openly by an experimenter who had not been informed about group assignment. When unaware that they were being observed, simulators were significantly less responsive to suggestion and engaged in substantially more role-inappropriate behavior. In contrast, the responsiveness of nonsimulating students was not affected by the presence of an experimenter, and they exhibited little role-inappropriate behavior even when alone. These data indicate that the responses of suggestible individuals reflect internally generated changes in experience and are not due to simple intentional compliance (i.e., faking).

Patients' pretreatment expectations of chemotherapy-related nausea are an independent predictor of anticipatory nausea.

Based on extensive research with animals, classical conditioning theorists have come to regard contingency as the primary factor in the development of conditioned responses. However, recent experimental work with humans has suggested the possibility that participant expectations may also directly contribute to the development of conditioned responses. To date, this phenomenon has not been investigated in clinical settings. Anticipatory nausea (AN) in chemotherapy patients, widely viewed as the best established example of classical conditioning in clinical medicine, provides an opportunity to examine the contributions of patient expectations to the development of a conditioned response outside the laboratory. The present study of 59 breast cancer patients supported the hypothesis that pretreatment patient expectations make a significant (p < .03) contribution to the development of AN after statistically controlling for the strongest conditioning predictor, contingency. These data imply that patient expectations should be considered when evaluating conditioned responses to aversive medical treatments.

Classical conditioning and the placebo effect.

Stimulus substitution models posit that placebo responses are due to pairings of conditional and unconditional stimuli. Expectancy theory maintains that conditioning trials produce placebo response expectancies, rather than placebo responses, and that the expectancies elicit the responses. We tested these opposing models by providing some participants with information intended to impede the formation of placebo expectancies during conditioning trials and by assessing placebo expectancies. Although conditioning trials significantly enhanced placebo responding, this effect was eliminated by adding expectancies to the regression equation, indicating that the effect of pairing trials on placebo response was mediated completely by expectancy. Verbal information reversed the effect of conditioning trials on both placebo expectancies and placebo responses, and the magnitude of the placebo effect increased significantly over 10 extinction trials. These data disconfirm a stimulus substitution explanation and provide strong support for an expectancy interpretation of the conditioned placebo enhancement produced by these methods.

The development of anticipatory nausea in patients receiving adjuvant chemotherapy for breast cancer.

Previous research on anticipatory nausea in cancer patients has focused on its occurrence in the clinic before chemotherapy infusions. The present study is the first, to our knowledge, to examine the development of anticipatory nausea across eight chemotherapy infusions for three time periods (night before, morning of, and immediately prior to each infusion). Based on classical conditioning experiments conducted with animal subjects, we hypothesized that the severity of anticipatory nausea would increase as the time for scheduled infusions approached. Eighty-two women diagnosed with Stage I or II breast cancer were assessed for the intensity of anticipatory nausea at three time periods prior to eight scheduled infusions of outpatient adjuvant chemotherapy. Analyses indicated a significant interaction between number of infusions experienced and temporal proximity to the infusion, supporting the hypothesis. Changes in the severity of anticipatory nausea across infusions were consistent with conditioned learning predictions. These results contribute to a growing recognition of the importance of conditioning principles for understanding side effects of chemotherapy for cancer and may have implications for the management of side effects secondary to a variety of pharmacotherapies in clinical practice.