The placebo puzzle: putting together the pieces

A phenomenology of the 'placebo effect': taking meaning from the mind to the body

Most mainstream attempts to understand the "placebo effect" invoke expectancy theory, arguing that expecting certain outcomes from a treatment or intervention can manifest those outcomes. Expectancy theory is incompatible with the phenomena of placebo responses, more appropriately named "meaning responses." The expectancy account utilizes reflexive consciousness to connect a world of conceptual representations to mechanical physiology. An alternative account based upon Merleau-Ponty's motor intentionality argues that the body understands and is capable of responding to meanings without the need for any conceptual or linguistic content. A motor intentional framework of meaning poses dramatic implications for the interpretation of clinical trials and in the clinical practice of medicine. Most strongly, it argues that the empathic physician can facilitate the physiologic effects of treatments through skillful participation and manipulation of the meaning response.

Unexpected effects of methylphenidate in attention-deficit/hyperactivity disorder reflect decreases in core/secondary symptoms and physical complaints common to all children

Abstract Hypotheses concerning unexpected, psychostimulant-related effects reported in previous studies were examined by separating behavioral/physical complaints highly specific to methylphenidate (MPH) from those that (a) may mimic core/secondary symptoms of the disorder, or (b) are commonly reported by unmedicated children in the general population. Sixty-five children with attention-deficit/hyperactivity disorder (ADHD) participated in a double-blind, placebo-controlled, within-subject (crossover) experimental design and received a placebo and four MPH doses in counterbalanced order following baseline assessment. Behavioral and physical complaints were significantly higher under baseline relative to placebo and the four immediate-release MPH conditions (5 mg, 10 mg, 15 mg, and 20 mg) across three symptom categories: ADHD core/secondary symptoms; symptoms commonly reported in the general population, including unmedicated children with ADHD; and symptoms highly specific to MPH. No significant differences were found among active drug conditions. Past unexpected findings of psychostimulant effects in ADHD may be due to the inclusion of scale items that reflect core/secondary features of ADHD and normally occurring behavioral/physical complaints in children.

Patient satisfaction with primary care: a comparison between conventional care and traditional Chinese medicine

OBJECTIVES

The evaluation of patient satisfaction with traditional Chinese medicine (TCM) versus conventional medicine (COM) in Swiss primary care.

DESIGN

A cross-sectional study was performed with questionnaires aimed at fulfilment of expectations, perceived treatment effects, and patient satisfaction.

SETTING

Participants were 51 certificated TCM physicians, 71 COM physicians, and 2530 adult patients.

RESULTS

Among patients seeking primary care in Switzerland, those who choose a conventional physician with additional certification in TCM have a higher chance of being completely satisfied with their treatment than patients who choose a physician educated only in COM.

CONCLUSIONS

Physicians who supply TCM in addition to COM are able to satisfy the needs of their patients more completely than solely COM-practicing physicians. Explanations for this difference include less frequent side effects in TCM, better TCM physician-patient interaction with longer duration of consultation, and different treatment expectations of patients seeking TCM.

Chemotherapy-Induced Nausea and Vomiting

Despite treatment advances, nausea and vomiting, especially anticipatory nausea and vomiting, delayed nausea and vomiting and nausea alone, are still the most common, expected and feared side effects among patients receiving chemotherapy. Of the 70 to 80% of cancer patients who experience chemotherapy-induced nausea and vomiting many will delay or refuse future chemotherapy treatments and contemplate stopping all treatments because of fear of further nausea and vomiting. The purpose of this chapter is to provide an overview of the patho-psychophysiology of CINV, the recommended guidelines for standard treatment, and highlight newer targeted treatment approaches.

Do Bach flower remedies have a role to play in pain control?

This paper explores the potentiality of Bach flower remedies as a means of pain relief through a retrospective case-study analysis to establish how clients suffering with painful conditions responded to the therapy.

RESULTS

Of 384 subjects, 41 suffered pain. Of these, 46% felt treatment had relieved their pain; in 49% the physical outcome was unknown. About 88% of all subjects reported an improvement in their emotional outlook.

DISCUSSION

The role of placebo and its influence on the study's key features: focus shift from physical pain to emotional outlook, and the importance of the client-practitioner relationship and belief in the therapy.

CONCLUSION

The use of Bach flower remedies has brought about positive emotional changes in the majority of clients in this study. Whilst it is difficult to draw a definitive conclusion as to significance of the therapeutic value of these remedies in relation to pain above that of a placebo, the results are encouraging. In particular, relief of negative emotions and promotion of positive thought including how clients opened up about, and dealt with, emotional issues. The indication is that potential for Bach flower remedies as a therapeutic agent in the relief of pain does exist and is worthy of further qualitative and quantitative investigation through robust, purpose-designed studies to replicate and progress the results shown here.

Correlates of placebo response in the treatment of sexual dysfunction in women: a preliminary report

INTRODUCTION

Placebo responses have been large across a number of clinical trials for treatment of women's sexual dysfunction. Studying placebo responses may elucidate predictors of symptom reduction and responsiveness to intervention.

AIM

To determine the correlates of placebo response in participants enrolled in a clinical trial for female sexual dysfunction.

METHODS

We analyzed data from 16 women with sexual arousal and orgasmic dysfunction who were randomized to receive 8 weeks of placebo treatment within a larger randomized controlled trial. Using nonparametric correlations, we tested whether age, length of relationship, psychological symptoms, and scores on self-report measures predicted change in sexual function with placebo treatment.

MAIN OUTCOME MEASURE

Female Sexual Function Index.

RESULTS

Consistent with findings from other studies, we found a significant improvement in sexual function scores after 8 weeks of treatment with placebo. We also found that age and length of relationship predicted the magnitude of change in sexual function across treatment. Changes in relationship adjustment, but not relationship adjustment at baseline, predicted the magnitude of improvement in sexual function scores. We observed no relationship between psychological symptom severity and change in sexual function.

CONCLUSIONS

Participant age and length of relationship predicted subsequent magnitude of change in sexual function scores during treatment with placebo. In addition, relationship adjustment covaried with changes in sexual function. Our findings suggest that "placebo effects" may represent underlying factors that influence the way in which women respond to the process of treatment.

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.

Dispositional predictors of placebo responding: a motivational interpretation of flower essence and gratitude therapy

OBJECTIVES

The aim of this study was to test a motivational interpretation of placebo responding using two different types of placebo therapy, one using flower essences and the other a nonspecific psychological therapy. The motivational concordance interpretation is that therapeutic rituals that are consistent with self-defining or self-actualizing goals have a nonspecific therapeutic benefit independently of expectancy.

METHODS

Study 1 was a replication of an earlier flower essence outcome study but with additional outcome and predictor variables: 167 people completed questionnaires in return for free flower essence treatment. Predictor variables consisted of two measures of spirituality, optimism, expectancy, and attitudes and beliefs to complementary medicine. Outcome was assessed after 3 weeks. In Study 2, 90 people took part in "gratitude therapy" for improved sleep quality over one night in return for questionnaire completion (trait gratitude, spirituality, and expectancy).

RESULTS

Study 1 confirmed previous research: Trait spirituality predicted perceived improvement. This improvement was independent of optimism (P<.001), cannot be explained by acquiescence or social desirability, and was independent of a highly conservative test of expectancy (P=.02). In Study 2, trait gratitude predicted perceived sleep improvement independently of expectancy (P=.01): Spirituality did not correlate with improvement.

CONCLUSIONS

These data suggest that in addition to expectations, degree of engagement in a positive, therapeutic ritual determines the extent of the placebo response. The placebo response depends in part on the interaction (i.e., the degree of concordance) between the type of therapy and the participant's personality: Dispositional predictors vary with the type of placebo therapy.

What is a health expectation? Developing a pragmatic conceptual model from psychological theory

INTRODUCTION

Examination of the existing literature in respect of health expectations revealed both ambiguity in relation to terminology, and relatively little work in respect of how abstract theories of expectancy in the psychological literature might be used in empirical research into the influence of expectations on attitudes and behaviours in the real world. This paper presents a conceptual model for the development of health expectations with specific reference to Alzheimer's disease.

METHOD

Literature review, synthesis and conceptual model development, illustrated by the case of a person with newly diagnosed, early-stage Alzheimer's disease, and her caregiver.

OUTCOME

Our model envisages the development of a health expectation as incorporating several longitudinal phases (precipitating phenomenon, prior understanding, cognitive processing, expectation formulation, outcome, post-outcome cognitive processing).

CONCLUSION

Expectations are a highly important but still relatively poorly understood phenomenon in relation to the experience of health and health care. We suggest a pragmatic conceptual model designed to clarify the process of expectation development, in order to inform future research into the measurement of health expectations and to enhance our understanding of the influence of expectations on health behaviours and attitudes.

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.

Goal activation, expectations, and the placebo effect

Motivational factors receive little attention in current theories of the placebo effect. Reasons for this position are reviewed, and an argument is made for reconsidering the influence of motivation on the placebo effect. The authors hypothesize that nonconscious goals alter reactions to a placebo expectation. Specifically, the authors predict that the placebo effect is most likely to occur when individuals have a goal that can be fulfilled by confirmation of the placebo expectation. The authors tested this notion in 5 experiments. The results demonstrate the role of motivation in the placebo effect across a variety of symptom domains and via 4 different goal activation techniques. Moreover, this moderating effect occurred for both positive and negative placebo expectations, across different placebo effect measures, and in brief laboratory experiments as well as in lengthier studies. It is argued that theories regarding the placebo effect should incorporate motivational factors.

Effectiveness of fludrocortisone and salt in preventing syncope recurrence in children: a double-blind, placebo-controlled, randomized trial

OBJECTIVES

We sought to evaluate the effectiveness of salt and fludrocortisone versus placebo in the prevention of syncope recurrence in children.

BACKGROUND

Intravascular volume expansion with fludrocortisone and salt has been reported to be effective in the treatment of syncope in children. However, no pediatric placebo-controlled data are available on the effectiveness of this mode of therapy.

METHODS

Thirty-three children with syncope or severe presyncope were randomized in a double-blinded fashion to receive either fludrocortisone 0.1 mg/day and salt 1 g/day or placebo two capsules per day for one year. All children had a positive tilt test before enrollment.

RESULTS

Thirty-two children (20 female) had follow-up. Their age was (mean +/- SD) 13.9 +/- 2.5 years. The number of syncopal episodes before therapy was 4.4 +/- 4.8. Therapy was continued for 176 +/- 117 days, and follow-up including time after discontinuation of medications was 1.2 +/- 0.8 years. The demographics were similar in the 18 children treated with fludrocortisone and salt compared with the 14 children on placebo. Data for up to one year of randomization were included in analyses. Symptoms recurred in 10 of 18 children on fludrocortisone and salt and in 5 of 14 children on placebo (p < 0.04). Children on placebo had no symptoms until they discontinued their study medications.

CONCLUSIONS

These data, coupled with the reported comparable effect of many medications used in the treatment of syncope, raise the potential of a significant placebo effect with pharmacologic therapy.

Patient expectation is a strong predictor of severe nausea after chemotherapy

BACKGROUND

Patients may use their past experiences with nausea, as well as information about the incidence of nausea from chemotherapy that other patients have experienced, to form a prediction, or response expectancy, of nausea from their own upcoming chemotherapy. Mounting evidence suggests that these expectancies relating to nausea are significant predictors, and, likely, contributing factors to the development of treatment-related nausea.

METHODS

The patients in the current study were participants in the control arm of a multicenter clinical trial conducted between November 1999 and July 2001 by the University of Rochester Community Clinical Oncology Program. All patients in the current report were age >/= 18 years and were about to begin a first cancer treatment regimen containing doxorubicin.

RESULTS

Expectancy of nausea assessed before patients received their first doxorubicin-based chemotherapy treatment was found to be a strong predictor of subsequent nausea and in fact was stronger than previously reported predictive factors, including age, nausea during pregnancy, and susceptibility to motion sickness. Women who believed it was "very likely" that they would have severe nausea from chemotherapy were five times more likely to experience severe nausea than fellow patients who thought its occurrence would be "very unlikely."

CONCLUSIONS

Further studies confirming an expectancy of nausea as a risk factor are warranted as are studies examining the benefit to a patient's quality of life from modifying antiemetic treatment guidelines to take into account symptom expectancies. Finally, ethically acceptable interventions that are designed to reduce patients' nausea expectancies or increase their expectancies of nausea control should be developed and studied.