An exploratory study on the effects of an expectancy manipulation on chemotherapy-related nausea

Distinguishing Immunologic and Behavioral Effects of Vaccination

The interpretation of vaccine efficacy estimands is subtle, even in randomized trials designed to quantify the immunologic effects of vaccination. In this article, we introduce terminology to distinguish between different vaccine efficacy estimands and clarify their interpretations. This allows us to explicitly consider the immunologic and behavioral effects of vaccination, and establish that policy-relevant estimands can differ substantially from those commonly reported in vaccine trials. We further show that a conventional vaccine trial allows the identification and estimation of different vaccine estimands under plausible conditions if one additional post-treatment variable is measured. Specifically, we utilize a "belief variable" that indicates the treatment an individual believed they had received. The belief variable is similar to "blinding assessment" variables that are occasionally collected in placebo-controlled trials in other fields. We illustrate the relations between the different estimands, and their practical relevance, in numerical examples based on an influenza vaccine trial.

A Basis for Strengthening Coping Strategies and Treatment Expectations in Patients Undergoing Emetogenic Pelvic-Abdominal Radiotherapy: A Longitudinal Study

Objectives: To study the relationship between coping strategies and nausea during emetogenic pelvic-abdominal radiotherapy, and to describe the patients' rationales for their expectations regarding nausea. Methods: Patients (n = 200: 84% women, mean age 64 years, 69% had gynecological, 27% colorectal, and 4% had other malignances) longitudinally participated during pelvic-abdominal radiotherapy. We measured adopted coping strategies using the Mental Adjustment to Cancer scale and the patients' rationales for their expectations regarding nausea at baseline. The patients registered nausea and vomiting daily during the radiotherapy period (mean 36 + Standard Deviation 10 days). Results: Patients who experienced nausea (n = 128, 64%) during the radiotherapy period graded a lower score on "Fighting Spirit" (median, md, score 51, P = .031) and a higher score on "anxious preoccupation" (md 18, P = .040) compared to patients who did not experience nausea (n = 72, 36%), md 54 and md 17. More of the patients for whom "Helpless-Hopeless" represented the most predominant response experienced nausea (100%) or vomited (56%) compared to patients adopting "Fighting Spirit": 62% experienced nausea (P = .011) and 20% vomited (P = .014). Only four (6%) of the nausea-free patients had expected themselves to be at increased risk for nausea. Of the patients who became nauseous, 22 (17%) patients had expected themselves to be at increased risk for nausea (P = .017), based on previous experience. Conclusion: Patients adopting maladaptive coping strategies or patients expecting nausea based on previous experiences, were more likely to experience nausea than other patients when undergoing emetogenic pelvic-abdominal radiotherapy. Cancer care professionals may identify patients adopting maladaptive coping strategies or having high nausea expectations by applying the MAC scale and self-assessment of expected nausea risk and guide these patients to adopt adaptive coping strategies and strengthen their expectations on successful prevention of nausea.Trial registration number: Clinicaltrials.gov: NCT00621660.

Understanding Placebo and Nocebo Responses Based on a Randomized Sham-Controlled Study on Acupuncture in Integrative Cancer Care

Objective: Since placebo and nocebo-responses during acupuncture therapy are rarely studied in clinical contexts, the objective was to investigate placebo and nocebo-responses in a clinical context through comparing positive and negative side-effects between genuine and sham acupuncture, and to identify factors modifying placebo and nocebo-responses. Methods: Patients reported positive side-effects (non-intended positive effects) or negative side-effects (non-intended negative effects) of genuine (penetrating; n = 109) or sham (telescopic non-penetrating; n = 106) acupuncture during 5 weeks of chemoradiation for cancer. Results: The genuine and the sham acupuncture group reported rather similar frequencies of positive (P-values .223-.800) or negative (P-values .072-1.0) side-effects: relaxation 59%/57% of the patients, improved mood 46%/38%, improved sleep 38%/38%, pain-reduction 36%/28%, tiredness 42%/42%, feeling cold 37%/31%, sweating 23%/21%, and dizziness 20%/12%. Positive side-effects occurred in 79% of patients who highly believed acupuncture to be effective, compared to in 0% of patients who did not believe. Other factors associated with placebo-response were female sex (P = .042), anxious mood (P = .007), depressed mood (P = .018), and blinding-success (P = .033). Factors associated with nocebo response were female sex (P = .049), younger age (P = .010), and needle-induced pain (P = .014). Sham-treated patients experiencing positive side-effects experienced better quality of life at the end of the treatment period (mean, m 64 on a scale 0-100 millimetres, Standard Deviation, SD, ±26.1 mm) than those who did not (m 48 ± 25.5 mm), P = .048 (adjusted for other characteristics). Conclusions: Clinically significant levels of placebo and nocebo effects commonly occurred during acupuncture therapy in integrative cancer care and this paper identified factors modifying these responses. This implicates that acupuncture-delivering therapists striving to maximize placebo-responses and minimize nocebo-responses may considering strengthen the patient's treatment expectations, and offer a pleasant, pain-free, acupuncture treatment.

Chemotherapy-induced Emesis: Experienced Burden in Life, and Significance of Treatment Expectations and Communication in Chemotherapy Care

OBJECTIVE

Because antiemetics have become more effective and integrative therapies such as acupuncture are used in combination with antiemetics, people receiving chemotherapy for cancer today might expect less emesis than in the past. It is not previously described if and how people receiving modern antiemetics during chemotherapy experience emesis. The objective of this study was to describe experiences regarding emesis among persons undergoing emetogenic chemotherapy, and how it affects their quality of life, daily life and work. A further aim was to describe views on the significance of treatment expectations and communication with healthcare personnel while undergoing chemotherapy for cancer.

METHOD

Fifteen participants (median age 62 years, n = 1 man and n = 14 women, with breast (n = 13) or colorectal (n = 2) cancer) undergoing adjuvant or neo-adjuvant highly or moderately emetogenic chemotherapy were interviewed individually. The data were then analyzed using inductive thematic analysis.

RESULTS

Three themes described the participants' experiences: "Your whole life is affected, or continues as usual," covering descriptions of emesis limiting some participants' everyday lives, while others experienced no emesis at all or had found ways to manage it. Overall, participants described satisfaction with their antiemetic treatment. "Experiences and expectations more important than information", that is, the participants reported wanting all the information they could get about possible adverse effects of treatment, although they believed previous experiences were more important than information in creating expectations about treatment outcomes. The participants reported that being seen as a unique person was of utmost importance: "Meet me as I am." This creates trust in healthcare personnel and a feeling of safety and security in the situation.

CONCLUSIONS

These findings underline the importance of person-centered care and support in creating positive treatment expectations. Future research is called for regarding the potential antiemetic effects of positive communication regarding strengthening positive treatment expectations during emetogenic chemotherapy.

Persistence of gastrointestinal symptoms in irritable bowel syndrome and ulcerative colitis: study protocol for a three-arm randomised controlled trial (SOMA.GUT-RCT)

INTRODUCTION

Ulcerative colitis (UC) and irritable bowel syndrome (IBS) are distressing chronic diseases associated with abdominal pain and altered bowel habits of unknown aetiology. Results from previous studies indicate that, across both diseases, increased levels of illness-related anxiety and dysfunctional symptom expectations contribute to symptom persistence. Thus, comparing both disorders with regard to common and disease-specific factors in the persistence and modification of gastrointestinal symptoms seems justified. Our primary hypothesis is that persistent gastrointestinal symptoms in UC and IBS can be improved by modifying dysfunctional symptom expectations and illness-related anxiety using expectation management strategies.

METHODS AND ANALYSIS

To assess the extent to which persistent somatic symptoms are modifiable in adult patients with UC and IBS, we will conduct an observer-blinded, three-arm randomised controlled trial. A total of 117 patients with UC and 117 patients with IBS will be randomised into three groups of equal size: targeted expectation management aiming to reduce illness-related anxiety and dysfunctional symptom expectations in addition to standard care (SC, intervention 1), non-specific supportive treatment in addition to SC (intervention 2) or SC only (control). Both active intervention groups will comprise three individual online consultation sessions and a booster session after 3 months. The primary outcome is baseline to postinterventional change in gastrointestinal symptom severity.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of the Hamburg Medical Association (2020-10198-BO-ff). The study will shed light onto the efficacy and mechanisms of action of a targeted expectation management intervention for persistent gastrointestinal symptoms in patients with UC and IBS. Furthermore, the detailed analysis of the complex biopsychosocial mechanisms will allow the further advancement of aetiological models and according evidence-based intervention strategies.

TRIAL REGISTRATION NUMBER

ISRCTN30800023.

Treatment expectations seem to affect bowel health when using acupuncture during radiotherapy for cancer: Secondary outcomes from a clinical randomized sham-controlled trial

OBJECTIVE

To investigate if frequent stools ("diarrhoea"), infrequent stools ("constipation"), capacity in daily activities and Quality of Life (QoL) differed between patients treated with verum or sham acupuncture, and if patients with more positive treatment expectations differed regarding frequent stools and infrequent stools from patients with less positive treatment expectations.

METHODS

In this randomized sham controlled trial, 200 patients received verum traditional penetrating acupuncture or sham acupuncture using a telescopic non-penetrating sham-needle 2-3 times a week during abdominal-pelvic radiotherapy (12 needling sessions during median 5 radiotherapy weeks). The patients registered stool frequency once a week, and registered capacity in daily activities and QoL at the start and end of radiotherapy, and at a one-month follow-up.

RESULTS

In the verum acupuncture group, 29 of 96 answering patients (30 %) experienced frequent stools and 7 (7 %) experienced infrequent stools at least one week of radiotherapy. In the sham acupuncture group, 21 of 97 (22 %) experienced frequent stools (p = 0.175) and 10 (10 %) experienced infrequent stools (p = 0.613). Patients with low treatment expectancy were more likely than other patients to experience frequent stools (60 % versus 26 %, p = 0.014) but not to experience infrequent stools (25 % versus 12 %, p = 0.334).

CONCLUSION

Penetrating acupuncture was not effective for frequent stools or for infrequent stools and did not improve capacity in daily activities or QoL in patients undergoing pelvic-abdominal irradiation for cancer more than non-penetrating acupuncture. Since patients with low acupuncture treatment expectations were more likely to experience frequent stools compared to other patients, non-specific treatment effects warrant further studies.

Optimizing expectations about endocrine treatment for breast cancer: Results of the randomized controlled psy-breast trial

Background

Medication side effects are strongly determined by non-pharmacological, nocebo mechanisms, particularly patients’ expectations. Optimizing expectations could minimize side effect burden. This study evaluated whether brief psychological expectation management training (EXPECT) optimizes medication-related expectations in women starting adjuvant endocrine therapy (AET) for breast cancer.

Method

In a multisite randomized controlled design, 197 women were randomized to EXPECT, supportive therapy (SUPPORT), or treatment as usual (TAU). The three-session cognitive-behavioral EXPECT employs psychoeducation, guided imagery, and side effect management training. Outcomes were necessity-concern beliefs about AET, expected side effects, expected coping ability, treatment control expectations, and adherence intention.

Results

Both interventions were well accepted and feasible. Patients’ necessity-concern beliefs were optimized in EXPECT compared to both TAU and SUPPORT, d = .41, p < .001; d = .40, p < .001. Expected coping ability and treatment control expectations were optimized compared to TAU, d = .35, p = .02; d = .42, p < 001, but not to SUPPORT. Adherence intention was optimized compared to SUPPORT, d = .29, p = .02, but not to TAU. Expected side effects did not change significantly.

Conclusion

Expectation management effectively and partly specifically (compared to SUPPORT) modified medication-related expectations in women starting AET. Given the influence of expectations on long-term treatment outcome, psychological interventions like EXPECT might provide potential pathways to reduce side effect burden and improve quality of life during medication intake.

Placebo and Nocebo Effects Across Symptoms: From Pain to Fatigue, Dyspnea, Nausea, and Itch

Placebo and nocebo effects are, respectively, the helpful and harmful treatment effects that do not arise from active treatment components. These effects have thus far been researched most often in pain. It is not yet clear to what extent these findings from pain can be generalized to other somatic symptoms. This review investigates placebo and nocebo effects in four other highly prevalent symptoms: dyspnea, fatigue, nausea, and itch. The role of learning mechanisms (verbal suggestions, conditioning) in placebo and nocebo effects on various outcomes (self-reported, behavioral, and physiological) of these different somatic symptoms is explored. A search of experimental studies indicated that, as in pain, the combination of verbal suggestion and conditioning is generally more effective than suggestion alone for evoking placebo and nocebo effects. However, conditioning appears more and verbal suggestions less relevant in symptoms other than pain, with the exception of placebo effects on fatigue and nocebo effects on itch. Physiological measures, such as heart rate, lung function, or gastric activity, are rarely affected even when self-reported symptoms are. Neurobiological correlates are rarely investigated, and few commonalities appear across symptoms. Expectations generally predict placebo and nocebo effects for dyspnea and itch but seem less involved in fatigue and nausea. Individual characteristics do not consistently predict placebo or nocebo effects across symptoms or studies. In sum, many conclusions deriving from placebo and nocebo pain studies do appear to apply to other somatic symptoms, but a number of important differences exist. Understanding what type of learning mechanisms for which symptom are most likely to trigger placebo and nocebo effects is crucial for generalizing knowledge for research and therapies across symptoms and can help clinicians to optimize placebo effects in practice.

Individual Factors Contributing to Nausea in First-Time Chemotherapy Patients: A Prospective Cohort Study

Objective

The expectation of developing side effects can enhance the likelihood to develop them – a phenomenon referred to as nocebo effect. Whether nocebo effects can be reduced by lowering negative expectancies, is not clear. The aim of this prospective study was to learn more about the factors contributing to nausea expectancy and their potential role in actual occurrence of nausea in patients undergoing chemotherapy for the first time in their life.

Methods

Patients scheduled for moderately emetogenic chemotherapeutic regimens filled in questionnaires to assess state anxiety and quality of life and to rate the expectancy of nausea as a side effect of chemotherapy. Patient diaries were used to monitor the severity of post-chemotherapy nausea in the 4 days following chemotherapy administration. Bivariate analyses complemented by multiple regression analyses were performed to identify the relationship between nausea expectation and nausea occurrence.

Results

121 female patients (mean age 53 years) with completed questionnaires were included in the analyses. The majority of the patients had a diagnosis of breast cancer (86%). The two main sources for nausea expectancy were positive history of nausea in other situations and state anxiety. Patients with high expectancy levels (first quartile) experienced greater nausea than those with lower expectancy levels. Bivariate analyses revealed a weak but non-significant association between nausea expectation and post-chemotherapy nausea. When controlling for age, type of cancer, history of nausea, state and trait anxiety, and global quality of life, positive history of nausea (OR = 2.592; 95% CI, 1.0 to 6.67; p < 0.05), younger age (OR = 0.95; 95% CI, 0.92 to 0.99; p < 0.05), and a lower quality of life (OR = 0.97; 95% CI, 0.94 to 1.0; p < 0.05), but not nausea expectancy (OR = 1.014; 95% CI, 0.51 to 2.02; p = 0.969), predicted the occurrence of post-chemotherapy nausea.

Conclusion

In this female cohort, younger patients with lower initial quality of life and a positive history of nausea were at higher risk to develop nausea after first time chemotherapy. These patients may benefit from psychological co-interventions that aim to enhance quality of life.

Positive effects of acupressure bands combined with relaxation music/instructions on patients most at risk for chemotherapy-induced nausea

PURPOSE

Research by our group has shown that acupressure bands are efficacious in reducing chemotherapy-induced nausea (CIN) for breast cancer patients who expect nausea, and that their effectiveness in controlling CIN can largely be accounted for by patients' expectations of efficacy, i.e., a placebo effect. The present research examined if the effectiveness of acupressure bands could be enhanced by boosting patients' expectation of the bands' efficacy.

METHODS

Two hundred forty-two chemotherapy-naïve patients with breast cancer who expected nausea were randomized. Arms 1 and 2 received acupressure bands, plus a relaxation MP3 and written handout that were either expectancy-enhancing (arm 1) or expectancy-neutral (arm 2). Arm 3 was the control without bands or MP3 and received standard care. All participants received guideline-specified antiemetics.

RESULTS

Peak CIN for arms 1, 2, and 3 on a 1-7 scale was 3.52, 3.55, and 3.87, respectively (p = 0.46). Because no differences were observed between arms 1 and 2 (primary analysis), we combined these two arms (intervention) and compared them to controls for the following analyses. A significant interaction was found between intervention/control and receiving doxorubicin-based chemotherapy (yes/no) and pre-treatment anxiety (high/low). Intervention patients receiving doxorubicin had lower peak CIN than controls (3.62 vs. 4.38; p = 0.02). Similarly, intervention patients with high pre-treatment anxiety had a lower peak CIN than controls (3.62 vs. 4.62; p = 0.01).

CONCLUSIONS

In breast cancer patients undergoing chemotherapy and having high CIN expectation, acupressure bands combined with a relaxation recording were effective in reducing CIN for patients who received doxorubicin or had high anxiety.

Influencing Side-Effects to Medicinal Treatments: A Systematic Review of Brief Psychological Interventions

Background: Nocebo effects contribute to a large proportion of the non-specific side-effects attributed to medications and are mainly generated through negative expectations. Previous reviews show that interventions designed to change participants' expectations have a small effect on pain experience. They are also effective in reducing side-effects caused by exposure to sham medications. To date, there has been no review of the influence of such interventions on symptoms attributed to real medicinal treatments. Objective: To review studies using a randomized controlled design testing the effect of brief psychological interventions compared to usual practice on the side-effect experience to medicinal treatments in healthy volunteers and patients. Methods: We searched Web of Science, Scopus, Medline, PsycINFO, PsycARTICLES, and Cochrane CENTRAL using search terms for randomized controlled trials along with "nocebo," "placebo effect," "medication," "side-effects," and associated terms. Studies were eligible if they studied a human population, used an active medicine, delivered a brief psychological intervention intended to influence side-effect reporting compared to usual care or no intervention, and used a randomized controlled design. Because of the heterogeneity of the literature we used a narrative synthesis and assessed evidence quality using the GRADE approach. Results: Our database search and supplementary search of the reference sections of included studies retrieved 50,140 citations. After screening, full text review and manual reference searches, 27 studies were included. The quality of the studies and evidence was judged to be low. The strongest and most consistent effect came from omitting side-effect information, although surprisingly de-emphasizing side-effects did not affect side-effect reporting. Other techniques, including priming, distraction, and altering the perception of branding, produced mixed results. Conclusion: Brief psychological interventions can influence side-effect reporting to active medications. Research is currently investigating new ways to de-emphasize side-effects whilst still upholding informed consent, but larger confirmatory trials with suitable control groups are needed. The literature in this area would be improved by more detailed reporting of studies.

Understanding rationales for acupuncture treated individuals' beliefs in acupuncture effects, to be able to maximize therapeutic results: A qualitative analysis

OBJECTIVE

To investigate how individuals expressed rationales for their beliefs regarding efficacy of acupuncture.

METHODS

Qualitative data from participants of two different randomized sham-controlled trials, of relaxing (non-cancer volunteers of the general population) or antiemetic (patients with cancer undergoing radiotherapy) effects of acupuncture was analyzed. Participants (n = 441) received genuine (n = 120 and n = 100) or sham (n = 121 and n = 100) (telescopic blunt sham-needle) relaxing or antiemetic acupuncture. The participants (n = 428; 97% response rate) expressed their belief regarding the efficacy of acupuncture, and n = 264 delivered qualitative rationales for their belief, analyzed using qualitative content analysis.

RESULTS

Of the 428 participants, 35 (8%) believed entirely that the acupuncture was effective, 209 (49%) believed much, 136 (32%) believed moderately, 39 (9%) believed a little, and 9 (2%) did not believe that the acupuncture was effective. Five categories and seven subcategories represented the meaning units of the central message of the rationales for the treatment belief. Participants with positive beliefs (believed entirely/much, n = 244) presented rationales related to: "Experienced positive effects", "Knowledge regarding effect-mechanisms of acupuncture", and "General trustworthiness of acupuncture". Participants with more negative beliefs (believed a little or not, n = 48) presented rationales related to: "Lack of feasibility of the acupuncture", "Varying effects", and "The effect is individual, not available for everybody".

CONCLUSION

In order to strengthen acupuncture treated patients' beliefs in the efficacy of acupuncture during clinical practice or research, acupuncture therapists may consider emphasizing these aspects in the therapeutic situation.

Complementary and alternative medicine self-care strategies for nausea in patients undergoing abdominal or pelvic irradiation for cancer: A longitudinal observational study of implementation in routine care

OBJECTIVE

To longitudinally describe practice of Complementary and Alternative Medicine (CAM) self-care strategies for nausea during radiotherapy.

METHODS

Two hundred patients daily registered nausea and practice of CAM self-care strategies, beside conventional antiemetic medications, for nausea during abdominal/pelvic irradiation (median five weeks) for gynecological (69%) colorectal (27%) or other tumors (4%).

RESULTS

During radiotherapy, 131 (66%) experienced nausea, and 50 (25%) practiced self-care for nausea at least once, for a mean (m) of 15.9days. The six of 50 patients who stayed free from nausea practiced self-care more frequent (m=25.8days) than the 44 patients experiencing nausea (m=14.5) (p=0.013). The CAM self-care strategies were: modifying eating (80% of all self-care practicing patients, 80% of the nauseous patients versus 83% of the patients free from nausea; ns) or drinking habits (38%, 41% vs 17%; ns), taking rests (18%, 20% vs 0%; ns), physical exercising (6%, 2% vs 33%; p=0.035), acupressure (4%, 5% vs 0%; ns) and self-induced vomiting (2%, 2% vs 0%; ns).

CONCLUSION

A fourth of patients undergoing emetogenic radiotherapy practiced CAM self-care for nausea, mostly by modifying eating or drinking habits. The CAM self-care practicing patients who did not become nauseous practiced self-care more frequent than the nauseous patients did. To make such self-care evidence based, we need studies evaluating its efficacy.

Different Disclosed Probabilities to Receive an Antiemetic Equally Decrease Subjective Symptoms in an Experimental Placebo Study: To Be or Not to Be Sure

PURPOSE

The purpose of this study was to examine whether the disclosed probability of receiving an antiemetic affects nausea.

METHODS

Forty-eight healthy participants (mean [SD] age, 26.8 [5.4] years; 50% female) were exposed to 5 × 2 minutes of nauseogenic body rotations on 2 days. On day 2, participants were randomized to 3 experimental groups that were given different instructions concerning the probability of receiving an antiemetic remedy (100%, 50%, or 0% probability), whereas all received an inert substance. Subjective symptoms, behavioral (rotation tolerance) measures, and physiologic (electrogastrogram) measures of nausea were assessed and mediator and moderator analyses performed for effects of expectations and psychological characteristics on outcomes.

FINDINGS

Disclosed probabilities of both 100% and 50% significantly reduced subjective symptoms of nausea in an equal manner compared with the 0% probability group from day 1 to day 2. This effect was found for neither rotation tolerance nor myoelectric gastric activity. Expectations and psychological characteristics did not affect the results found. Post hoc analyses revealed that women only seem to be susceptible to this placebo effect.

IMPLICATIONS

Nausea is susceptible to placebo effects independent of the disclosed probability of receiving a drug and of explicit expectations. In line with placebo research, this effect is probably attributable to central mechanisms, and it is speculated that it could be related to the reward circuitry and social interactions.

Sources of Placebo-Induced Relief From Nausea: The Role of Instruction and Conditioning

OBJECTIVES

It is well documented that expectancies alter the nauseous response. However, the lack of integration in research examining sources of expectancy has limited our understanding of how expectancies are formed and, consequently, our ability to intervene. The present study explored the role of both instructions and conditioning in placebo-induced relief from nausea.

METHODS

The study used a 2 × 2 between-subjects design with instruction and conditioning as factors with 56 healthy volunteers. The instruction manipulation involved randomizing participants to receive information that a sham treatment (a peppermint essence vapor) would reduce nausea or no such instructions. The conditioning manipulation involved further randomizing participants to have the first administration of this sham treatment paired with a surreptitious reduction in galvanic vestibular stimulation (GVS) intensity or no prior pairing. Nausea was induced through GVS. On test, all groups received the same level of GVS with the sham treatment present.

RESULTS

On test, participants who received instruction had significantly lower nauseous response scores than those who did not (F(1,46) = 6.71, p = .013), and those who received conditioning also reported less nausea than those who did not (F(1,46) = 5.20, p = .027), with the interaction between the two not reaching statistical significance (F(1,46) = 2.33, p = .13).

CONCLUSIONS

These findings indicate that placebo responding in nausea can be induced both through positive instructions and as little as one pairing of a treatment with a reduction in nausea, as well as their combination. This suggests that using placebo effects to complement antiemetic therapy may offer an important method of further reducing nausea in the clinic.

Neuro-Bio-Behavioral Mechanisms of Placebo and Nocebo Responses: Implications for Clinical Trials and Clinical Practice

The placebo effect has often been considered a nuisance in basic and particularly clinical research. This view has gradually changed in recent years due to deeper insight into the neuro-bio-behavioral mechanisms steering both the placebo and nocebo responses, the evil twin of placebo. For the neuroscientist, placebo and nocebo responses have evolved as indispensable tools to understand brain mechanisms that link cognitive and emotional factors with symptom perception as well as peripheral physiologic systems and end organ functioning. For the clinical investigator, better understanding of the mechanisms driving placebo and nocebo responses allow the control of these responses and thereby help to more precisely define the efficacy of a specific pharmacological intervention. Finally, in the clinical context, the systematic exploitation of these mechanisms will help to maximize placebo responses and minimize nocebo responses for the patient's benefit. In this review, we summarize and critically examine the neuro-bio-behavioral mechanisms underlying placebo and nocebo responses that are currently known in terms of different diseases and physiologic systems. We subsequently elaborate on the consequences of this knowledge for pharmacological treatments of patients and the implications for pharmacological research, the training of healthcare professionals, and for the health care system and future research strategies on placebo and nocebo responses.

An investigation of the effects of therapeutic touch plan on acute chemotherapy-induced nausea in women with breast cancer in Isfahan, Iran, 2012-2013

INTRODUCTION

Nausea is the worst and most prevalent chemotherapy-induced complication experienced by 70-80% of patients despite mediation therapy. Reduction of nausea is one of the most important roles of oncologist nurses. Today, complementary therapies in addition to classic medicine, because of their lower costs, receive much attention. Nonetheless, their safety and effectiveness are not yet proven. The purpose of this research was to investigate the effect of therapeutic touch plan as a complementary therapy on acute nausea in women with breast cancer in 2012-2013 in Isfahan, Iran.

MATERIALS AND METHODS

A quasi-experimental, single-blind, randomized control trial with three groups (control, placebo and intervention) was performed at the Isfahan Seyedolshohada (AS) Teaching Hospital, Isfahan, in 2012-2013. The intervention was therapeutic touch plan on women with breast cancer, with the three groups receiving the same medicine regimen. Information was recorded by a checklist after infusion of chemotherapy drugs. Data analysis was performed by SPSS, ANOVA and Kruskal-Wallis tests.

RESULTS

The ANOVA test showed that the therapeutic touch plan was significantly effective in reducing the duration of nausea compared with the control and placebo groups (P < 0.001). The Kruskal-Wallis test showed that the frequency of occurrence of nausea was also reduced in the intervention and placebo groups compared with the control group (P < 0.001). The therapeutic touch plan was significantly effective in delaying the onset of nausea compared with the control and placebo groups (P < 0.001).

CONCLUSION

This research showed that the therapeutic touch plan is effective in reducing acute chemotherapy-induced nausea; thus, education and implementation of the therapeutic touch plan is proposed for clinical nurses.

Placebo effects and their determinants in gastrointestinal disorders

Placebo effects in clinical trials have sparked an interest in the placebo phenomenon, both in randomized controlled trials (RCTs) and in experimental gastroenterology. RCTs have demonstrated similar short-term and long-term placebo response rates in gastrointestinal compared to other medical diagnoses. Most mediators and moderators of placebo effects in gastrointestinal diseases are also of similar type and size to other medical diagnoses and not specific for gastrointestinal diagnoses. Other characteristics such as an increase in the placebo response over time and the placebo-enhancing effects of unbalanced randomization were not seen, at least in IBS. Experimental placebo and nocebo studies underscore the 'power' of expectancies and conditioning processes in shaping gastrointestinal symptoms not only at the level of self-reports, but also within the brain and along the brain-gut axis. Brain imaging studies have redressed earlier criticism that placebo effects might merely reflect a response bias. These findings raise hope that sophisticated trials and experiments designed to boost positive expectations and minimize negative expectations could pave the way for a practical and ethically sound use of placebo knowledge in daily practice. Rather than focusing on a 'personalized' choice of drugs based on biomarkers or genes, it might be the doctor-patient communication that needs to be tailored.

The effectiveness of acupressure for the control and management of chemotherapy-related acute and delayed nausea: a randomized controlled trial

CONTEXT

Both positive and negative results have been reported in the literature from the use of acupressure at the P6 point, providing evidence of highly suggestive but not conclusive results.

OBJECTIVES

To clarify whether acupressure is effective in the management of chemotherapy-related nausea and vomiting.

METHODS

A randomized, three-group, sham-controlled trial was designed. Patients with cancer receiving chemotherapy were randomized to receive standardized antiemetics and acupressure wristbands, sham acupressure wristbands, or antiemetics alone. Primary outcome assessment (nausea) was carried out daily for seven days per chemotherapy cycle over four cycles. Secondary outcomes included vomiting, psychological distress, and quality of life.

RESULTS

Five hundred patients were randomized. Primary outcome analysis (nausea in Cycle 1) revealed no statistically significant differences between the three groups, although nausea levels in the proportion of patients using wristbands (both real and sham) were somewhat lower than those in the proportion of patients using antiemetics-only group. Adjusting for gender, age, and emetic risk of chemotherapy, the odds ratio of lower nausea experience was 1.18 and 1.42 for the acupressure and sham acupressure groups, respectively. A gender interaction effect was evident (P = 0.002). No significant differences were detected in relation to vomiting, anxiety, and quality-of-life measures.

CONCLUSION

No clear recommendations can be made about the use of acupressure wristbands in the management of chemotherapy-related nausea and vomiting as results did not reach statistical significance. However, the study provided evidence of encouraging signals in relation to improved nausea experience and warrants further consideration in both practice and further clinical trials.

TRIAL REGISTRATION

This trial is registered with the ISRCT register, number ISRCTN87604299.

Anticipatory nausea and vomiting due to chemotherapy

As a specific variation of chemotherapy-induced nausea and vomiting, anticipatory nausea and vomiting (ANV) appears particularly linked to psychological processes. The three predominant factors related to ANV are classical conditioning; demographic and treatment-related factors; and anxiety or negative expectancies. Laboratory models have provided some support for these underlying mechanisms for ANV. ANV may be treated with medical or pharmacological interventions, including benzodiazepines and other psychotropic medications. However, behavioral treatments, including systematic desensitization, remain first line options for addressing ANV. Some complementary treatment approaches have shown promise in reducing ANV symptoms. Additional research into these approaches is needed. This review will address the underlying models of ANV and provide a discussion of these various treatment options.

Optimizing expectations to prevent side effects and enhance quality of life in breast cancer patients undergoing endocrine therapy: study protocol of a randomized controlled trial

BACKGROUND

Adjuvant endocrine therapy can improve disease-free survival and time before recurrence in breast cancer patients. However, it is associated with considerable side effects that negatively affect patients' quality of life and cause non-adherence. The recently demonstrated effect of individual expectations on side-effect development (nocebo effect) suggests that psychological factors play a role in the prevention of side effects. The aim of this study is to evaluate cognitive-behavioral side-effect prevention training (SEPT) for breast cancer patients. This article describes the study protocol and applied research methods.

METHODS/DESIGN

In a randomized controlled trial, 184 female breast cancer patients are assigned to receive either SEPT, standard medical care or a manualized supportive therapy at the start of adjuvant endocrine treatment. SEPT consists of three sessions of cognitive-behavioral training including psychoeducation to provide a realistic view of endocrine therapy, imagination-training to integrate positive aspects of medication into daily life, and side-effect management to enhance expectations about coping ability. Side effects three months after the start of endocrine therapy serve as primary outcomes. Secondary outcomes include quality of life, coping ability and patients' medication adherence. Patients' expectations (i.e., expectations about side effects, coping ability, treatment and illness) are analyzed as mediators.

DISCUSSION

The optimization of expectations might be a potential pathway in health care to improve patients' quality of life during long-term medication intake. The results will provide implications for a possible integration of evidence-based prevention training into clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov, (NCT01741883).

Individual differences in chemotherapy-induced anticipatory nausea

Anticipatory Nausea (AN) is a severe side effect of chemotherapy that can lead cancer patients to discontinue their treatment. This kind of nausea is usually elicited by the re-exposure of the patients to the clinical context they need to attend to be treated. There has been considerable agreement that AN represents a paradigmatic example of Pavlovian conditioning, and within this framework, several behavioral interventions have been proposed in order to prevent this phenomenon. However, some studies have questioned the validity of the Pavlovian approach, suggesting that CS-US associations are neither necessary nor sufficient for AN to occur. The data and the alternative theories behind such criticisms are discussed. Additionally, it is suggested that animal models of AN could be enriched by taking into account rats' individual differences.

Development of the Stanford Expectations of Treatment Scale (SETS): A tool for measuring patient outcome expectancy in clinical trials

Background

A patient’s response to treatment may be influenced by the expectations that the patient has before initiating treatment. In the context of clinical trials, the influence of participant expectancy may blur the distinction between real and sham treatments, reducing statistical power to detect specific treatment effects. There is therefore a need for a tool that prospectively predicts expectancy effects on treatment outcomes across a wide range of treatment modalities.

Purpose

To help assess expectancy effects, we created the Stanford Expectations of Treatment Scale (SETS): an instrument for measuring positive and negative treatment expectancies. Internal reliability of the instrument was tested in Study 1. Criterion validity of the instrument (convergent, discriminant, and predictive) was assessed in Studies 2 and 3.

Methods

The instrument was developed using 200 participants in Study 1. Reliability and validity assessments were made with an additional 423 participants in Studies 2 and 3.

Results

The final six-item SETS contains two subscales: positive expectancy (α = 0.81–0.88) and negative expectancy (α = 0.81–0.86). The subscales predict a significant amount of outcome variance (between 12% and 18%) in patients receiving surgical and pain interventions. The SETS is simple to administer, score, and interpret.

Conclusion

The SETS may be used in clinical trials to improve statistical sensitivity for detecting treatment differences or in clinical settings to identify patients with poor treatment expectancies.

The nocebo effect and its relevance for clinical practice

Negative expectations deriving from the clinical encounter can produce negative outcomes, known as nocebo effects. Specifically, research on the nocebo effect indicates that information disclosure about potential side effects can itself contribute to producing adverse effects. Neurobiological processes play a role in the nocebo effect, and this article provides a selective review of mechanistic research on the nocebo effect. Comparatively little attention has been directed to clinical studies and their implications for daily clinical practice. The nocebo response is influenced by the content and the way information is presented to patients in clinical trials in both the placebo and active treatment conditions. Nocebo effects adversely influence quality of life and therapy adherence, emphasizing the need for minimizing these responses to the extent possible. Evidence further indicates that the informed consent process in clinical trials may induce nocebo effects. This article concludes with ethical directions for future patient-oriented research and routine practice.

Treatment of Nausea and Vomiting During Chemotherapy

Nausea and vomiting are two of the most troubling side effects patients experience during chemotherapy. While newly available treatments have improved our ability to manage nausea and vomiting, anticipatory and delayed nausea and vomiting are still a major problem for patients receiving chemotherapy. Many cancer patients will delay or refuse future chemotherapy treatments and contemplate stopping chemotherapy altogether because of their fear of experiencing further nausea and vomiting. The purpose of this article is to provide an overview of the patho-psychophysiology of chemotherapy-induced nausea and vomiting and the recommended guidelines for treatment.