Evaluating how placebos produce change. Logical and causal traps and understanding cognitive explanatory mechanisms

An account of medical treatment, with a preliminary account of medical conditions

In this article, I present a philosophical account of medical treatment. In support of this account, I offer a suggestive account of medical conditions. The account of medical treatment uses three desiderata to demarcate treatment from non-treatment. Namely, a treatment should: (1) be describable by features that enable it to be standardized and characterized as a discrete intervention, (2) target a specific medical condition, and (3) have the possibility of being effective. The account of medical conditions underlies the second desideratum and attempts to tie medical conditions closely to biological dysfunction, while also including some conditions for which biological dysfunction is absent or its presence uncertain. I offer a simple typology of treatments and show how the accounts are relevant to treatment effectiveness, disease, placebos, contested treatments, and treatment standardization.

Placebos Without Deception: Outcomes, Mechanisms, and Ethics

Scientific research indicates that open-label and dose-extending placebos (that patients know are placebos) can elicit behavioral, biological, and clinical outcome changes. In this chapter, we present the state-of-the-art evidence and ethical considerations about open-label and dose-extending placebos, discussing the perspective of giving placebos with a rational, as dose extension of active drugs, or expectancy boosters. Previous comprehensive reviews of placebo use have considered how to harness placebo effects in medicine and the need to focus on elements of the clinical encounter as well as patient-clinician relations. Here, we illustrate the similarities and differences between standard (deceptive) placebos, open-label placebos and dose-extending placebos. We conclude that placebos without deception would override ethical barriers to their clinical use. This paves the way to future large-scale, pragmatic randomized trials that investigate the potential of ethical open-label and dose-extending placebos to improve patients' outcomes, and reduce side effects.

Effects of placebos without deception compared with no treatment: A systematic review and meta-analysis

OBJECTIVE

To investigate the clinical efficacy of open-label placebos compared with no treatment in a systematic review and meta-analysis.

METHODS

We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations (OvidSP), EMBASE (OvidSP), and clinical trials registers and screened reference lists. The search was run on 27^th April 2015. We included all randomized controlled trials of any medical condition with open-label placebo and no-treatment groups. Authors independently assessed records and extracted data. We excluded nonrandomized trials and nonclinical studies. Risk of bias was assessed using Cochrane criteria. We used random-effects model for meta-analysis.

RESULTS

We screened 348 publications, assessed 24 articles for eligibility and identified five trials (260 participants) that met inclusion criteria. The clinical conditions were: irritable bowel syndrome, depression, allergic rhinitis, back pain, and attention deficit hyperactivity disorder. The risk of bias was moderate. We found a positive effect for nondeceptive placebos (standardized mean difference 0.88, 95% CI 0.62 to 1.14, P < 0.00001, I² = 1%).

CONCLUSIONS

Open-label placebos appear to have positive clinical effects compared to no treatment. Caution is warranted when interpreting these results due to the limited number of trials identified, lack of blinding, and the fact that positive messages were included alongside open-label placebos. Larger definitive trials are now warranted to explore the potential patient benefit of open-label placebos, to investigate the relative contributions of positive suggestions, and ethical implications.

Nonspecific Feelings Expected and Experienced during or Immediately after Electroacupuncture: A Pilot Study in a Teaching Situation

BACKGROUND

Some feelings elicited by acupuncture-type interventions are "nonspecific", interpretable as resulting from the placebo effect, our own self-healing capacities-or, indeed, the flow of qi. Expectation is thought to contribute to these nonspecific effects. Here we describe the use of two innovative 20-item questionnaires (EXPre₂₀ and EXPost₂₀) in a teaching situation.

METHODS

Respondents were acupuncture students or practitioners on electroacupuncture (EA) training courses (N = 68). EXPre₂₀ and EXPost₂₀ questionnaires were completed before and after receiving individualised treatment administered by colleagues. Respondents were also asked about their prior experience of EA or transcutaneous electroacupuncture stimulation (TEAS).

RESULTS

Respondents expected significantly more items to change than not to change, but significantly fewer were experienced as changing. Increases in given questionnaire items were both expected and experienced significantly more often than decreases. "Tingling", "Relaxation", and "Relief" or "Warmth" were most often expected to increase or were experienced as such, and "Pain" and "Tension" to decrease or experienced as decreasing. Expectations of change or no change were confirmed more often than not, particularly for "Tingling" and "Tension". This was not the result of the personal respondent style. Cluster analysis suggested the existence of two primary feeling clusters, "Relaxation" and "Alertness".

CONCLUSIONS

Feelings experienced during or immediately after acupuncture-type interventions may depend both on prior experience and expectation.

Placebo/Nocebo Symptom Reporting in a Sham Herbal Supplement Trial

The present study examined reports of placebo and nocebo symptoms in a college sample. The study was presented under the guise of a clinical trial to evaluate the effectiveness of an over-the-counter herbal supplement intended to enhance cognitive performance. Participants were informed they would be receiving either an herbal supplement or a placebo, and each was provided with a mock list of possible beneficial and adverse effects of the “supplement.” In fact, all participants received placebo. Symptoms were endorsed by a significant majority of participants following placebo ingestion. More important, results indicated that the few participants who believed they received an herbal supplement endorsed (via self-report) significantly more symptoms than those who believed they received a placebo. Neither anxiety nor social desirability was significantly related to symptom reporting. Results suggest that beliefs concerning treatment received may subsequently affect the degree of placebo response in a no-treatment group. Implications for clinical trials and future research are discussed.

Effect of sexual diary keeping and self-evaluation on female sexual function and depression: A pilot study

OBJECTIVES

The aim of the trial was to assess the effect of self-evaluation and sexual diary keeping on female sexual function and depressive symptoms in women diagnosed with sexual dysfunction.

METHODS

A single-arm non-randomised trial included 30 women (53 ± 7 years of age) with female sexual dysfunction (Female Sexual Function Index [FSFI] < 27) and a stable partnership duration of 5-40 years. Female sexual function was assessed by sexual, psychological and gynaecological history taking and validated questionnaires including the FSFI, Female Sexual Distress Scale (FSDS) and Hamilton Depression Scale (HDS), before and after 4 weeks of sexual diary keeping.

RESULTS

A subjective improvement in communication of sexual problems was reported by 60% of participants; no participants reported any worsening of communication. FSFI and FSDS scores were, respectively, 18.0 ± 7.7 and 22.0 ± 10.0 at baseline and 20.2 ± 7.2 and 20.6 ± 11.5 after 4 weeks. HDS score decreased from 6.0 ± 4.0 at baseline to 4.4 ± 2.7 after 4 weeks (p = 0.042).

CONCLUSIONS

Self-evaluation and sexual diary keeping may improve aspects of sexual life, such as couple communication, without a direct effect on variables measured with validated questionnaires on different domains of sexual function.

Genetics and the placebo effect: the placebome

Placebos are indispensable controls in randomized clinical trials (RCTs), and placebo responses significantly contribute to routine clinical outcomes. Recent neurophysiological studies reveal neurotransmitter pathways that mediate placebo effects. Evidence that genetic variations in these pathways can modify placebo effects raises the possibility of using genetic screening to identify placebo responders and thereby increase RCT efficacy and improve therapeutic care. Furthermore, the possibility of interaction between placebo and drug molecular pathways warrants consideration in RCT design. The study of genomic effects on placebo response, 'the placebome', is in its infancy. Here, we review evidence from placebo studies and RCTs to identify putative genes in the placebome, examine evidence for placebo-drug interactions, and discuss implications for RCTs and clinical care.

Understanding and translating the knowledge about placebo effects: the contribution of psychology

PURPOSE OF REVIEW

Recent articles have summarized the literature on the neurobiological mechanisms involved in placebo effects. In this article, we review and evaluate the status of the psychological mechanisms in theory and research regarding placebo effects.

RECENT FINDINGS

Currently, the placebo effect literature concentrates more on neurobiological mechanisms than on psychological mechanisms. Both theoretical and empirical coverage of the psychological mechanisms are typically limited to two variables: conditioning and verbally induced expectations. Because psychological processes take center stage in mediating the link between the therapeutic context and placebo responding, greater effort is needed to build empirically derived and theoretically complex psychological process models. Such models would include a broader array of psychological constructs and mechanisms.

SUMMARY

Research and theory on placebo effects has illuminated much regarding the neurobiological mechanisms. The psychological mechanisms, however, have received much less attention. Expanding our knowledge regarding the psychological processes involved in placebo responding would open up opportunities for developing nondeceptive intervention techniques that encourage placebo responses. Ultimately, a concerted empirical effort to clarify the psychological model underlying placebo effects could merge with the evolving neurobiological model to fulfill the promise that placebo effects have for improving patient outcomes.

Expectancy, Self-Efficacy, and Placebo Effect of a Sham Supplement for Weight Loss in Obese Adults

This study examined the role of expectancy in the placebo effect of a sham dietary supplement for weight loss in 114 obese adults with metabolic syndrome. All participants received lifestyle education and were randomized to 1 of 3 conditions: (1) a daily placebo capsule and told that they were taking an active weight loss supplement, (2) daily placebo and told they had a 50% random chance of receiving either the active or placebo, or (3) no capsules. At 12 weeks, weight loss and metabolic outcomes were similar among the 3 groups. Participants in both groups that took capsules showed decreased weight loss self-efficacy and increased expectations of benefit from dietary supplements. Participants not taking capsules showed the opposite. Adverse events were more frequently reported in groups taking capsules than those who were not. These findings suggest that supplements without weight loss effects may have nocebo effects through diminished self-efficacy.

Validation of the Korean Version of the Acupuncture Expectancy Scale

Objectives

Expectancy has been shown to affect patients’ responses to acupuncture therapy. However, no validated measure of expectancy for acupuncture is available in the Korean language. The Acupuncture Expectancy Scale (AES), a 4-item self-reporting questionnaire, is the validated instrument for measuring expectancies regarding acupuncture therapy. We translated the AES into Korean and examined its test–retest reliability and construct validity.

Methods

The AES was translated using a forward and backward translation procedure. Internal consistency was assessed in 275 participants with item-total correlations. Construct validity was also assessed by performing principal component analysis and correlating scores on the scale with the participants’ intention to receive acupuncture therapy. Test–retest reliability was assessed in 33 participants by calculating Cronbach's α and Spearman rank correlation coefficients.

Results

Internal consistency was high (Cronbach's α=0.910). Principal component analysis showed that expectancy of acupuncture treatment accounted for 79.2% of the variance. The AES was positively correlated with participants’ intention to receive acupuncture treatment (r=0.695, p<0.001). Test–retest reliability in 33 of the 275 participants was adequate, with the Spearman rank correlation coefficient ranging from 0.500 to 0.737 (p<0.001).

Conclusions

The Korean version of the AES is a valid and reliable instrument for measuring patients’ expectancies regarding acupuncture treatment in the Korean population.

Adherence, expectations and the placebo response: why is good adherence to an inert treatment beneficial?

OBJECTIVE

The current study sought to better understand why good adherence to a placebo treatment has been reliably associated with health benefits. We proposed a model where initial expectations shape adherence, which then influences subsequent expectations that affect placebo response.

DESIGN

Seventy-two participants were told that they were enrolling in a study of physical activity and memory, and were asked to increase their physical activity by 35% for two weeks (placebo treatment).

MAIN OUTCOME MEASURES

Adherence to this physical activity target was measured by pedometer. Expectations and short-term memory (free recall) were assessed before and after physical activity.

RESULTS

Initial expectations predicted adherence to physical activity (r = .27, p < .03), but adherence did not predict subsequent expectations (r = .06, p = .60). Testing a multi-step meditational model revealed that initial expectations predicted better memory even after controlling for adherence, subsequent expectations, baseline memory and gender (c' = 1.10, 95% CI = .46-1.74). Stronger expectations for memory improvement predicted better memory performance, but adherence and later expectations did not mediate this association.

CONCLUSIONS

Good adherence to a placebo may reflect strong treatment expectations which may convey benefits by enhancing the non-specific effects of treatment.

Developing a patient-centered outcome measure for complementary and alternative medicine therapies I: defining content and format

BACKGROUND

Patients receiving complementary and alternative medicine (CAM) therapies often report shifts in well-being that go beyond resolution of the original presenting symptoms. We undertook a research program to develop and evaluate a patient-centered outcome measure to assess the multidimensional impacts of CAM therapies, utilizing a novel mixed methods approach that relied upon techniques from the fields of anthropology and psychometrics. This tool would have broad applicability, both for CAM practitioners to measure shifts in patients' states following treatments, and conventional clinical trial researchers needing validated outcome measures. The US Food and Drug Administration has highlighted the importance of valid and reliable measurement of patient-reported outcomes in the evaluation of conventional medical products. Here we describe Phase I of our research program, the iterative process of content identification, item development and refinement, and response format selection. Cognitive interviews and psychometric evaluation are reported separately.

METHODS

From a database of patient interviews (n = 177) from six diverse CAM studies, 150 interviews were identified for secondary analysis in which individuals spontaneously discussed unexpected changes associated with CAM. Using ATLAS.ti, we identified common themes and language to inform questionnaire item content and wording. Respondents' language was often richly textured, but item development required a stripping down of language to extract essential meaning and minimize potential comprehension barriers across populations. Through an evocative card sort interview process, we identified those items most widely applicable and covering standard psychometric domains. We developed, pilot-tested, and refined the format, yielding a questionnaire for cognitive interviews and psychometric evaluation.

RESULTS

The resulting questionnaire contained 18 items, in visual analog scale format, in which each line was anchored by the positive and negative extremes relevant to the experiential domain. Because of frequent informant allusions to response set shifts from before to after CAM therapies, we chose a retrospective pretest format. Items cover physical, emotional, cognitive, social, spiritual, and whole person domains.

CONCLUSIONS

This paper reports the success of a novel approach to the development of outcome instruments, in which items are extracted from patients' words instead of being distilled from pre-existing theory. The resulting instrument, focused on measuring shifts in patients' perceptions of health and well-being along pre-specified axes, is undergoing continued testing, and is available for use by cooperating investigators.

Placebo expectations and the detection of somatic information

In a laboratory study we examined the hypothesis that placebo expectations enhance the initial identification of placebo-relevant sensations over placebo-irrelevant sensations. Participants (N = 102) were randomly assigned to one of three expectation groups. In the first group, participants ingested a placebo capsule and were told it was caffeine (deceptive expectation). In a second group, participants ingested a placebo capsule and were told it may be caffeine or it may be a placebo (double-blind expectation). Participants in the third group were given no expectation. All participants then tallied the placebo-relevant and placebo-irrelevant sensations they experienced during a 7-min period. Participants in the deceptive expectation group identified more placebo-relevant sensations than placebo-irrelevant sensations. No-expectation participants identified more placebo-irrelevant sensations than placebo-relevant sensations. Participants given the double-blind expectation identified an equal amount of placebo-relevant and irrelevant sensations. The amount of both placebo-relevant and placebo-irrelevant sensations detected mediated the relationship between the expectation manipulation and subsequent symptom reports. These data support the position that expectations cause placebo responding, in part, by altering how one identifies bodily sensations.

A controlled trial of working memory training for children and adolescents with ADHD

This study assessed the efficacy of a 5-week, intensive working memory training program for 52 children and adolescents (ages 7-17) who had Attention-Deficit/Hyperactivity Disorder (ADHD) and other comorbid diagnoses. This study provided a treatment replication since the waitlist control group also completed training and was included in the follow-up data analyses. Parents and teachers completed paper-and-pencil measures of working memory, executive functioning, and ADHD symptoms at baseline, posttreatment, and 4-month follow-up. Parent ratings indicated that participants improved on inattention, overall number of ADHD symptoms, initiation, planning/organization, and working memory. Teacher ratings approached significance at posttreatment and at 4-month follow-up on and Initiate scale. Working memory training appears promising as an intervention in improving executive functioning and ADHD symptoms.

From medicine to psychotherapy: the placebo effect

If placebos have been squeezed out of medicine to the point where their official place in in clinical trials designed to identify their own confounding effect, the placebo effect nevertheless thrives in psychotherapy. Not only does psychotherapy dispose of placebo effects that are less available to medicine as it becomes increasingly technological and preoccupied with body parts, but factors of the sort inhibiting the use of placebos in medicine have no equivalent in psychology. Medicine today is disturbed by the placebo effect in a way psychotherapy is not. Psychotherapy does not have to grapple with such a disconcerting paradox as successful sham surgery, and unlike those physicians who once pretended to treat the patient's body while actually attempting to treat the mind, the psychotherapist can treat the mind in all frankness. Perhaps it is because psychotherapy is less burdened by doubts about the placebo effect that it was able to come to its aid when it was orphaned by medicine. It is vain to expect something with so long a history as the placebo effect to disappear from the practices of healing.

Informed consent in complementary and alternative medicine

The objective of this study was to examine complementary and alternative medicine (CAM) practitioners' (i) attitudes toward informed consent and (ii) to assess whether standards of practice exist with respect to informed consent, and what these standards look like. The design and setting of the study constituted face-to-face qualitative interviews with 28 non-MD, community-based providers representing 11 different CAM therapeutic modalities. It was found that there is great deal of variability with respect to the informed consent process in CAM across providers and modalities. No unique profession-based patterns were identified. The content analysis yielded five major categories related to (i) general attitude towards the informed consent process, (ii) type and amount of information exchange during that process, (iii) disclosure of risks, (iv) discussions of alternatives, and (v) potential benefits. There is a widespread lack of standards with respect to the practice of informed consent across a broad range of CAM modalities. Addressing this problem requires concerted and systematic educational, ethical and judicial remedial actions. Informed consent, which is often viewed as a pervasive obligation is medicine, must be reshaped to have therapeutic value. Acknowledging current conceptions and misconception surrounding the practice of informed consent may help to bring about this change. More translational research is needed to guide this process.

Reconsidering the placebo response from a broad anthropological perspective

This paper considers how the full range of human experience may catalyze a placebo response. The placebo effect has been characterized as something to control in clinical research, something to cultivate in clinical practice and something present in all healing encounters. We examine domains in which the term 'placebo' is used in discourse: clinical research, clinical practice, media representations of treatment efficacy and lay interpretations of placebo--an underresearched topic. We briefly review major theoretical frameworks proposed to explain the placebo effect: classical conditioning, expectancy, the therapeutic relationship and sociocultural 'meaning.' As a corrective to what we see as an overemphasis on conscious cognitive approaches to understanding placebo, we reorient the discussion to argue that direct embodied experience may take precedence over meaning-making in the healing encounter. As an example, we examine the neurobiology of rehearsing or visualizing wellness as a mode of directly (performatively) producing an outcome often dismissed as a 'placebo response.' Given body/mind/emotional resonance, we suggest that the placebo response is an evolutionarily adaptive trait and part of healing mechanisms operating across many levels--from genetic and cellular to social and cultural.

Placebo effects: clinical aspects and neurobiology

Placebo effects are beneficial health outcomes not related to the relatively direct biological effects of an intervention and can be elicited by an agent that, by itself, is inert. Understanding these placebo effects will help to improve clinical trial design, especially for interventions such as surgery, CNS-active drugs and behavioural interventions which are often non-blinded. A literature review was performed to retrieve articles discussing placebo implications of clinical trials, the neurobiology of placebo effects and the implications of placebo effect for several disorders of neurological relevance. Recent research in placebo analgesia and other conditions has demonstrated that several neurotransmitter systems, such as opiate and dopamine, are involved with the placebo effect. Brain regions including anterior cingulate cortex, dorsolateral prefrontal cortex and basal ganglia have been activated following administration of placebo. A patient's expectancy of improvement may influence outcomes as much as some active interventions and this effect may be greater for novel interventions and for procedures. Maximizing this expectancy effect is important for clinicians to optimize the health of their patient. There have been many relatively acute placebo studies that are now being extended into clinically relevant models of placebo effect.

Do "placebo responders" exist?

The placebo effect has been the subject of much controversy. For a scientific investigation of placebo effects to advance it is important to establish whether a placebo response in any particular illness is reliable - i.e., if there is a response to a single placebo administration there will also be a placebo response to the repeated administration of a similar placebo in similar conditions. A positive answer would allow more sophisticated clinical trial designs and more precise basic research experiments on the placebo effect. This article reviews experiments that used multiple administrations of placebo to answer the question "do reliable placebo responders exist?" This paper also examines the evidence for the existence of a consistent placebo responder, i.e. a person who responds to placebo in one situation will respond in another condition or using a different type of placebo ritual. Much of the existing evidence for these two questions was performed before 1967. This early evidence is contradictory, methodologically weak and is sufficiently old to be considered medical history. Since 1969, at least eight experiments exposed asthma patients to multiple administrations of placebo given with deceptive suggestions that the "treatment" was an active medication. While the results of this research are not unequivocal, and may not be equivalent to non-deceptive conditions, this line of inquiry suggests that if a reliable and consistent placebo response exists it could be detected within this population. Finally, this paper proposes one model to rigorously investigate the stability of placebo responses.

Acupuncture expectancy scale: development and preliminary validation in China

OBJECTIVE

Expectancy has been shown to affect the response to psychological and medical interventions; however, the lack of validated measure of expectancy in the setting of acupuncture limits the quantitative evaluation of the effects of expectancy on clinical response to acupuncture therapy. We seek to develop and validate an instrument that measures patients' expected response from acupuncture.

SETTING/DESIGN

We developed the acupuncture expectancy scale by eliciting items from patients and then conducted a survey study in two phases to test the reliability and validity of the instrument among 200 subjects at six outpatient acupuncture clinics in Beijing, China.

RESULTS

Our final scale consisted of four items measuring the expectation of improvement of illness, enhanced coping, increased vitality, and symptom alleviation as a result of acupuncture therapy. Scores of acupuncture expectancy scales ranged from four to 20, with a median of 17, and 21% at the maximum score. No item had over 5% missing data. Internal consistency (Cronbach's alpha coefficient) was .82. Principal components analysis revealed one general component accounting for 64% of the variance. Expectancy of response was positively correlated with selected questions of perceived efficacy (0.44), satisfaction (0.49), and confidence in prescribed acupuncture therapy (0.51), all with P < .001.

CONCLUSION

We developed a simple four-item instrument with valid and reliable score that measures expectancy about acupuncture therapy and correlates to subject reported response. The reliability and validity of acupuncture expectancy scale score needs to be tested in other types of populations. Incorporating this instrument in clinical trials can evaluate the role of expectancy as part of the complex social-behavioral component of acupuncture therapy.

Further evidence for individual differences in placebo responding: an interactionist perspective

OBJECTIVE

A prior investigation found that individuals low in optimism are more likely to follow a negative placebo (nocebo) expectation. The present study tested the hypothesis that individuals high in optimism are more likely to follow a positive placebo expectation.

METHODS

Individuals (N=56) varying in their level of optimism were randomly assigned to one of three conditions. In the first condition, participants were given the expectation that a placebo sleep treatment would improve their sleep quality (placebo expectation condition). In the second condition, participants engaged in the same sleep treatment activity but were not given the positive placebo expectation (treatment control condition). Finally, a third group did not receive the positive placebo expectation and also did not engage in the placebo sleep treatment (no-placebo control condition).

RESULTS

Optimism was positively associated with better sleep quality in the placebo expectation condition (r=.48, P<.05). Optimism scores were not associated with better sleep quality in either the treatment control condition (r=-.17, P=.46) or the no-placebo control condition (r=-.24, P=.35).

CONCLUSION

Dispositional optimism relates to placebo responding. This relationship, however, is not manifested in a simple increase or decrease in all types of placebo responding. Rather, it appears that, as optimism increases, response to the positive placebo expectation increases, whereas response to nocebo expectation decreases. It is recommended that future research on personality and placebo effects consider the interaction between situational and dispositional variables.

Treatment-related changes in objectively measured parenting behaviors in the multimodal treatment study of children with attention-deficit/hyperactivity disorder

The present study examined treatment outcomes for objectively measured parenting behavior in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD). Five hundred seventy-nine ethnically and socioeconomically diverse children with ADHD-combined type (ages 7.0-9.9 years) and their parent(s) were recruited at 6 sites in the United States and Canada and randomly assigned to 1 of 4 treatment groups for 14 months of active intervention: medication management (MedMgt), intensive behavior therapy, combination of the 2 (Comb), or a community-treated comparison (CC). Baseline and posttreatment laboratory observations of parent-child interactions were coded by observers blind to treatment condition. Comb produced significantly greater improvements in constructive parenting than did MedMgt or CC, with effect sizes approaching medium for these contrasts. Treatment effects on child behaviors were not significant. The authors discuss the importance of changes in parenting behavior for families of children with ADHD and the need for reliable and objective measures in evaluating treatment outcome.

Expectations and Placebo Response: A Laboratory Investigation into the Role of Somatic Focus

It has been theorized that expectations are an important causal determinant of the placebo effect. Placebo expectations, however, do not always yield placebo effects. In a laboratory study, we tested the hypothesis that one's level of somatic focus moderates the effect of placebo expectations on placebo responding. We also varied whether participants were told the placebo was a drug, could either be a drug or placebo, or was a placebo. The results revealed that individuals who thought they were taking a drug (i.e., unconditional expectations) reported more placebo symptoms when they closely focused on their symptoms. Individuals told they may or may not be receiving a drug (i.e., conditional expectations) did not differ from control participants regardless of how closely they attended to their symptoms. The findings have theoretical implications for expectancy models of the placebo effect as well as for practical research comparing the type of expectations held by individuals in clinical trials and clinical practice.

Understanding placebo, nocebo, and iatrogenic treatment effects

Placebo and nonplacebo treatments have both positive and negative effects on patient outcomes. To better understand the patterning of treatment effects, three specific interventions will be discussed that are reported to produce more harm than benefit: critical incident stress debriefing, group therapy for adolescents with conduct disorders, and psychotherapy for dissociative identity disorder. In each case, there is an interaction between mechanisms thought to underlie both placebo and specific treatment effects. Mechanisms hypothesized to underlie placebo and nocebo effects include patient expectancy, self-focused attention to symptoms, motivation to change, and sociocultural role-enactment cues. In the three treatments discussed, specific mechanisms interact with nonspecific mechanisms to produce iatrogenic effects. To advance knowledge, it is important both to specify the theory of treatment and its expected outcomes and to put the theory to test. Only with attention to the empirical findings from programmatic research of specific and nonspecific effects and their interaction is it possible to improve the outcomes of treatment beyond the status quo.

Reconsidering the role of personality in placebo effects: dispositional optimism, situational expectations, and the placebo response

OBJECTIVE

Prior investigations have failed to find reliable personality differences in placebo responding. The present study tests the hypothesis that personality and situational variables interact to determine placebo responding.

METHODS

Optimists and pessimists were randomly assigned to one of three conditions. In the first condition, the participants were told that they were to ingest a pill that would make them feel unpleasant (deceptive-expectation group). In the second condition, the participants were told that they were to ingest a pill that would make them feel either unpleasant or was an inactive substance (conditional-expectation group). Finally, a third group was told they were to ingest a pill that was inactive (control group).

RESULTS

Pessimists were more likely than optimists to follow a negative-placebo expectation when given a deceptive expectation, but not when given a conditional expectation.

CONCLUSION

The personality variable optimism-pessimism relates to placebo responding when individuals are given a deceptive but not a conditional expectation. This suggests that personality and situational variables interact to determine placebo responding.

One size does not fit all: aptitude x treatment interaction (ATI) as a conceptual framework for complementary and alternative medicine outcome research. Part 1--what is ATI research?

When multiple treatment choices are available, the question is not just "which treatment is the best?" but more importantly "best or better for whom, when, and why?" Aptitude (or attribute) by treatment interaction (ATI) is a research paradigm that attempts to examine exactly that--how outcome depends on the match or mismatch between patients' specific characteristics and the treatment they receive. The purpose of this two-part paper is to introduce ATI methods as a conceptual framework into complementary and alternative medicine/integrative medicine (CAM/IM) outcome research. Part 1 presents key concepts in ATI research. Part 2 will present ATI research designs and discusses their applications to the examination of the relationships between individuals and therapies, and the illumination of the mechanisms that make therapies differentially effective. Based on this examination, we conclude that ATI research offers invaluable insights into the multifaceted package of care typically delivered in contemporary medicine and therefore should be included in the portfolio of all CAM/IM outcome research.

Individual Differences in Response to Randomly Assigned Active Individualized Homeopathic and Placebo Treatment in Fibromyalgia: Implications of a Double-Blinded Optional Crossover Design

OBJECTIVE

To assess individual difference characteristics of subgroups of patients with fibromyalgia (FM) patients with respect to the decision to stay in or switch from randomly-assigned verum or placebo treatment during an optional crossover phase of a double-blinded homeopathy study.

DESIGN

Double-blinded, randomized, placebo-controlled, optional crossover clinical trial.

PARTICIPANTS

Fifty-three (53) community-recruited patients with FM entered the optional crossover phase.

INTERVENTION

Two homeopaths jointly selected an individualized homeopathic remedy for all patients. The pharmacy dispensed either verum LM remedy or indistinguishable placebo in accord with randomized assignment for 4 months and the patient's optional crossover decision for an additional 2 months.

OUTCOME MEASURES

Patients completed a battery of baseline state/trait questionnaires, including mood, childhood neglect and abuse, and trait absorption. They rated global health (whole person-centered) and tender point pain on physical examination (disease-specific) at baseline, 3 months, and 6 months.

RESULTS

Rates of optional crossover from verum to placebo or placebo to verum were comparable (p = 0.6; 31%, and 41%, respectively). The switch subgroups had greater baseline psychologic issues (emotional neglect in placebo-switch; depression and anger in verum-switch). The verum-stay subgroup scored highest on treatment helpfulness and included all six exceptional responders who fell, prior to crossover, into the top terciles for improvement in both global health and pain. Patients staying in their randomly assigned groups, active or placebo (n = 34), scored significantly higher in trait absorption than did those who switched groups (n = 19).

CONCLUSION

Individual difference factors may predict better and poorer responders with FM to specific and nonspecific effects of homeopathic and placebo treatment.

Fostering a healing presence and investigating its mediators

The purpose of this paper is the exploration and explication of the complex phenomena of "healing presence" and of appropriately supportive theoretical approaches to integrate emerging models for research design. Healing presence is described as an interpersonal, intrapersonal, and transpersonal to transcendent phenomenon that leads to a beneficial, therapeutic, and/or positive spiritual change within another individual (healee) and also within the healer. An integrated framework merging knowledge from diverse fields of research develops the multiple elements of healing presence, the healer, the healee's capacity for response and the healing effect as an entangled phenomenon. A conceptual systemic model is presented, and questions and dilemmas that emerge are delineated. An integrated qualitative-quantitative research design is proposed. A systemic relationship model, which includes the healer, the healee, and persons within the healee's environment is presented. The challenges are substantial, but the research questions are meaningful and worthwhile. The goal is to foster healing at bio-psycho-social-spiritual levels of the human being.

Affective disorder and epilepsy comorbidity: implications for development of treatments, preventions and diagnostic approaches

Concepts pertaining to affective disorder and epilepsy comorbidity are contributing appreciably to improvements in patient care. Several antiepileptic treatments have become important components of the management of bipolar affective disorder. In contrast, little progress has emerged in developing clinical applications of the anticonvulsant properties of the antidepressants in the treatment of the epilepsies. The slow onset of action of the antidepressants remains a major impediment to fully effective treatment of depressive episodes. Nevertheless, studies from experimental epileptology demonstrate that the anticonvulsant effects of the antidepressants occur rapidly and as a consequence of noradrenergic and/or serotonergic activation. These studies also demonstrate that adequate initial doses of the antidepressants are essential to rapid onset of anticonvulsant action. Pharmacokinetically valid loading dose paradigms are seemingly avoided with antidepressant drugs in humans because of potential toxicities and/or patient unacceptability. However, substantial progress has been made in reducing the adverse effect liability of the antidepressants. No longer is convulsive liability considered to stem from the therapeutic mechanisms of the anti-depressants. Rather, noradrenergic and serotonergic influences have demonstrable anticonvulsant properties. Other side effects may also be separable from the anticonvulsant and antidepressive effects of antidepressive treatments. The concept that the protracted process of antidepressant-induced beta-noradrenergic down-regulation is an essential prelude to the onset of mood benefit is no longer a sustainable premise. Nevertheless, increasing evidence underlies the possibility that knowledge of serotonergic and noradrenergic regulatory processes can be used to design strategies that will hasten the onset of antidepressive action. Similar optimism pervades efforts to determine the possibility that dual inhibition of serotonin and norepinephrine transporters will hasten onset of antidepressive action. Moreover, because noradrenergic and serotonergic systems are determinants of predisposition to seizures and to dysfunctional affective episodes, augmentation strategies may also be applicable to the use of antidepressant drugs in epilepsy and to the use of antiepileptic drugs such as carbamazepine in mood disorders. Recent studies have demonstrated that, in part, the therapeutic effectiveness of carbamazepine may stem from its marked capacity to elevate serotonin concentrations in the extracellular fluid of the brain via mechanisms that differ from those of the membrane reuptake inhibitors. Evidence suggests that the epilepsies and affective disorders may arise from a multiplicity of neurobiological abnormalities. A disorder in one individual may arise via different mechanisms than a phenomenologically similar disorder in another individual. Thus, diagnostic tools are needed to make mechanistic distinctions among individuals so that treatments can be appropriately developed and selected. In terms of epileptogenesis and affective disorder progression, neuroprotective paradigms for one individual may differ from those needed for another. Moreover, diagnostic technologies that are adequate to detect genetically and/or experientially determined vulnerability before the onset of a seizure or dysfunctional affective episode may be valuable steps toward achieving goals of prevention.