Introduction to placebo effects in medicine: mechanisms and clinical implications

The effects of low-level laser therapy on muscle strength and functional outcomes in individuals with knee osteoarthritis: a double-blinded randomized controlled trial

The purpose of this study was to compare the therapeutic effects of low-level laser therapy (LLLT) with 808 and 660 nm wavelength on muscle strength and functional outcomes in individuals with knee osteoarthritis (OA). A total of 47 participants were randomly assigned to the 808 nm, 660 nm, and sham control groups. Two LLLT groups received continuous LLLT with a mean power of 300 mW in different wavelengths at the knee joint 15 min a session three days per week for eight weeks, while the control group received the sham LED treatment. The knee strength and functional performance involving 30-s sit-to-stand, 40 m fast-paced walk, stair climbing, and the TUG test were measured at the baseline and one week after the interventions were completed. The results showed that knee extensor strength was more improved in the 808 nm group as compared to the 660 nm group (p < 0.001, d = 0.57) and the sham control (p < 0.001, d = 0.40), while increased flexor strength was demonstrated in the 808 nm (p = 0.009, d = 0.67) and sham control groups (p < 0.001, d = 0.97). The number of 30-s sit-to-stand was increased only in the 660 nm group (p = 0.006, d = 0.49). All three groups exhibited improvements in the other three functional performance-based tests after the interventions with no statistically significant differences among the groups. In conclusion, both intervention groups improved muscle strength and functional performance as compared to the control group. The 808 nm wavelength group showed better results in knee extensor strength. Therefore, laser therapy is suggested to be integrated into rehabilitation programs to improve muscle strength and functional performance in the population with knee OA.

Adjunctive Bright Light Therapy for Non-Seasonal Major Depressive Disorder: A Randomized Controlled Trial

This double-blind, randomized controlled trial assessed bright light therapy (BLT) augmentation efficacy compared with placebo light in treating non-seasonal major depressive disorder. The study participants belonged to a subtropical area (24.5°-25.5°N) with extensive daylight and included outpatients who had received stable dosages and various regimens of antidepressive agents for 4 weeks before enrollment. The outcomes were the 17-item Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale, and Patient Health Questionnaire-9, which were assessed at weeks 1, 2, and 4. A total of 43 participants (mean age 45 years, ranging from 22-81) were randomized into the BLT [n = 22] and placebo light groups [n = 21]. After a 4-week administration of morning light therapy (30 min/day), depressive symptoms did not reduce significantly, which might be due to the small sample size. Nonetheless, this study had some strengths because it was conducted in warmer climates, unlike other studies, and examined diverse Asians with depression. Our findings suggest that several factors, such as poor drug response, different antidepressive regimens, duration of BLT, and daylength variability (i.e., natural daylight in the environment) may influence the utility of add-on BLT. Researchers may consider these important factors for future non-seasonal depression studies in subtropical environments.

A double-blinded randomized clinical trial of pain perception during orthodontic treatment

Abstract Introduction Orthodontic movement can cause painful symptoms, especially in the early stages of treatment. Objective This study aimed to compare the performance of chewing gum and ibuprofen in pain control during the initial period of orthodontic treatment. Material and method A randomized blind clinical trial, with an allocation ratio of 1:1, was developed with patients aged ≥18 years old. The sample size was established considering a significance level of 5% and test power of 80%, resulting in a minimum of 30 volunteers per group (n=90). Participants were paired regarding sex, age, the severity of malocclusion, defined by the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN), and crowding, determined by Little’s irregularity index. The sample was randomly allocated to three groups: Group I (control) placebo; Group II chewing gum; and Group III Ibuprofen. Pain perception was evaluated by the Visual Analog Scale (VAS) in the first 24, 36, and 48 hours after activation of the orthodontic appliance. The data were analyzed by generalized linear models for repeated measures in time. Result No statistically significant difference (p>0.05) was observed among the groups for the methods of pain therapy evaluated in 24, 36, and 48 hours post-activation. Conclusion There was no difference among the method used for pain control during the orthodontic treatment.

Psilocybin microdosing does not affect emotion-related symptoms and processing: A preregistered field and lab-based study

BACKGROUND

Microdoses of psychedelics (i.e. a sub-hallucinogenic dose taken every third day) can reduce symptoms of depression, anxiety and stress according to anecdotal reports and observational studies. Research with medium to high doses of psilocybin points towards potential underlying mechanisms, including the modulation of emotion and interoceptive processing.

AIMS

In this preregistered study, we investigated whether psilocybin microdoses alter self-reported interoceptive awareness and whether repeated microdosing over 3 weeks modulates emotion processing and reduces symptoms of anxiety and depression.

METHODS

We used a double-blind, placebo-controlled, within-subject crossover design. Participants completed the Multidimensional Assessment of Interoceptive Awareness Questionnaire 1½ h after self-administering their second dose (or placebo), and the emotional go/no-go task and the shortened Depression Anxiety Stress Scale 1½ h after self-administering their seventh dose.

RESULTS

Our confirmatory analyses revealed that psilocybin microdosing did not affect emotion processing or symptoms of anxiety and depression compared with placebo. Our exploratory analyses revealed that psilocybin microdosing did not affect self-reported interoceptive awareness, that symptoms of depression and stress were significantly reduced in the first block compared with baseline, that participants broke blind in the second block and that there was no effect of expectations. Further research in a substance-naïve population with clinical range anxiety and depressive symptoms is needed to substantiate the potential beneficial effects of microdosing.

Efficacy of Auricular Acupuncture and Lavender Oil Aromatherapy in Reducing Preinterventional Anxiety in Cardiovascular Patients: A Randomized Single-Blind Placebo-Controlled Trial

Introduction: Auricular acupuncture at the "relaxation point" and lavender oil aromatherapy can reduce preoperative anxiety associated with increased mortality and morbidity. Data on the effect of combined auricular acupuncture and lavender oil aromatherapy in patients undergoing cardiovascular interventions with the use of local anesthesia or under conscious sedation are sparse. The authors sought to evaluate the efficacy of auricular acupuncture and lavender oil aromatherapy in reducing preinterventional anxiety in cardiovascular patients. Materials and Methods: Data of 80 consecutive patients undergoing diagnostic coronary angiography (n = 56) with or without percutaneous coronary intervention (n = 9) and right heart catheterization (n = 6), transcatheter aortic valve replacement (n = 17) and percutaneous mitral valve repair (MitraClip; n = 2) were analyzed. Patients were prospectively randomized to receive either preinterventional auricular acupuncture and lavender oil (Lavandula angustifolia) aromatherapy (verum group, n = 39) or combined sham auricular acupuncture and placebo oil aromatherapy (placebo group, n = 41). For the verum group bilateral auricular acupuncture was performed at the "relaxation point." State anxiety and blood pressure were assessed before and at 30 min after acupuncture and presternal oil application. State anxiety was defined as primary outcome measure and assessed using the Spielberger State Anxiety Inventory (STAI) for Adults form Y6. Intervention-specific anxiety was assessed by a 10-point numerical rating scale, and perceived treatment success by a single dichotomous question. Clinical blood pressure was further assessed. Results: After the intervention, the verum group had significantly decreased anxiety on the STAI compared with the placebo group (Δ = -4.18; 95% confidence interval = -8.31 to -0.05; p = 0.047). Significantly more patients reported subjective treatment success in the verum group (87.2%) than in the placebo group (65.9%, p = 0.035). No significant differences were observed regarding intervention-specific anxiety and blood pressure between the two groups. No serious adverse events occurred in any group. Conclusions: Combined auricular acupuncture and lavender oil aromatherapy can decrease preinterventional anxiety in cardiovascular patients and requires further investigation. German Clinical Trials Register (registration no. DRKS00023686).

Myths and Truths about Placebo Effect in Rehabilitation for Musculoskeletal Pain

This commentary provides the authors' point of view about the biopsychosocial perspective of placebo effect on musculoskeletal pain in the rehabilitation field.

Precision medicine reaching out to the patients in allergology - a German-Japanese workshop report

An expert workshop in collaboration of the German Society of Allergy and Clinical Immunology (DGAKI) and the Japanese Society of Allergy (JSA) provided a platform for key opinion leaders of both countries aimed to join expertise and to highlight current developments and achievements in allergy research. Key domains of the meeting included the following seven main sections and related subchapters: 1) basic immunology, 2) bronchial asthma, 3) prevention of allergic diseases, 4) food allergy and anaphylaxis, 5) atopic dermatitis, 6) venom allergy, and 7) upper airway diseases. This report provides a summary of panel discussions of all seven domains and highlights unmet needs and project possibilities of enhanced collaborations of scientific projects.

The Becoming of Online Healthcare through Entangled Power and Performativity: A posthumanist agential realist perspective

In this article we adopt Barad’s theory of agential realism to explore how power and performativity are simultaneously processual and ontologically entangled. We use the hyphenated term power-performativity to mobilize an exploration of how power is not an ‘outcome’ or ‘effect’ of, but an inseparable flow within, the processes of performativity through which the world is continuously becoming. This moves us beyond the traditional, anthropocentric take on the relationship between power and performativity which emphasizes human agency and linear cause-effect, toward an alternative understanding of organizational phenomena as always enacted through myriad intra-acting more-than-human actants. To empirically mobilize this approach, we explore power-performativity within online healthcare, enacted through personal online healthcare communities (POHCs). We explore multiple ‘diffraction gratings’ through which particular outcomes of online healthcare come to matter, while others are prevented from mattering. In doing so, we posit the suitability of Barad’s agential realism for further explorations of the dynamics of power and performativity in modes of organizing and organizational life and offer tools for how these may be done.

Sociability-based fitness approach in Parkinson's disease: Comparison with conventional rehabilitation

BACKGROUND AND PURPOSE

The effect of a sociability-based fitness approach on parkinsonian disability in patients with Parkinson's disease (PD) was assessed.

METHODS

Eighty patients diagnosed with PD were randomly assigned to either the group-based rehabilitation (GBR) group (n = 40) or the individual-based rehabilitation (IBR) group (n = 40). The primary outcome was the difference between the two groups in the mean change from baseline to post-training in the total score on the Unified Parkinson's Disease Rating Scale (UPDRS). The secondary outcomes included the change in mental status and the difference in the mean change from baseline to month 3 and month 6 in the total score on the UPDRS.

RESULTS

The mean (±SD) UPDRS scores were 72.0 ± 21.0 in the GBR group and 72.1 ± 18.6 in the IBR group. The UPDRS scores from baseline to post-training were 22.8 ± 13.5 in the GBR group and 10.9 ± 8.8 in the IBR group (difference 11.8 points; 95% confidence interval [CI] 5.0-18.6; p = 0.001). The difference between the groups from baseline to month 3 (difference 10.06 points; 95% CI 3.3-16.8) and the difference between the groups from baseline to month 6 (difference 11.7 points; 95% CI 4.9-18.5) were also significant (p = 0.004 and p = 0.001, respectively). The scores of cognitive function and depression had not changed significantly.

CONCLUSIONS

Patients receiving GBR demonstrated significant improvements in parkinsonian symptoms, suggesting that the sociability-based fitness can be applied to clinical treatment by sustaining the motivation in PD.

Placebo effects in allergen immunotherapy-An EAACI Task Force Position Paper

The placebo (Latin "I will please") effect commonly occurs in clinical trials. The psychological and physiological factors associated with patients' expectations about a treatment's positive and negative effects have yet to be well characterized, although a functional prefrontal cortex and intense bidirectional communication between the central nervous system and the immune system appear to be prerequisites for a placebo effect. The use of placebo raises certain ethical issues, especially if patients in a placebo group are denied an effective treatment for a long period of time. The placebo effect appears to be relatively large (up to 77%, relative to pretreatment scores) in controlled clinical trials of allergen immunotherapy (AIT), such as the pivotal, double-blind, placebo-controlled (DBPC) randomized clinical trials currently required by regulatory authorities worldwide. The European Academy of Allergy and Clinical Immunology (EAACI) therefore initiated a Task Force, in order to better understand the placebo effect in AIT and its specific role in comorbidities, blinding issues, adherence, measurement time points, variability and the natural course of the disease. In this Position Paper, the EAACI Task Force highlights several important topics regarding the placebo effect in AIT such as a) regulatory aspects, b) neuroimmunological and psychological mechanisms, c) placebo effect sizes in AIT trials, d) methodological limitations in AIT trial design and e) potential solutions in future AIT trial design. In conclusion, this Position Paper aims to examine the methodological problem of placebo in AIT from different aspects and also to highlight unmet needs and possible solutions for future trials.

Effect of zymomonas mobilis probiotic on cholesterol and its lipoprotein fractions and the intestinal regulation

Zymomonas mobilis have characteristics that classify it as probiotic. Thus, this study aimed to evaluate the effect of regular consumption of fermented broth of this strain on the intestinal function of individuals with changes in intestinal transit. This is a randomized, descriptive and quantitative clinical trial, a sample composed of undergraduate students from a university center in Caruaru. After screening for individuals with constipation according to the inclusion and exclusion criteria, only 13 agreed to participate in the study. They were divided into groups: group 1 received Zymomonas mobilis fermented broth once a day; group 2 also received the fermented broth in the same concentration cells being twice a day; group 3 received cell-free fermented broth once daily; and group 4, placebo, received saline once daily, all groups drank for fifteen days, and laboratory tests were performed to check lipid profile before and after that period. Observed an increase in evacuation days in all groups averaged in media 7.0-10.5 days. Groups 1 and 2 showed an increase in total cholesterol (0.5% and 5.0%, respectively), HDL cholesterol (4.1% and 24.1%), LDL cholesterol (4.9% and 8.4%), VLDL cholesterol (17.9% and 11.2%) and triglycerides (19.1% and 27.9%). In group 3, there was a reduction of total cholesterol (-2.4%), LDL cholesterol (-11.2%), VLDL cholesterol (-15.9%), triglycerides (-27.7%) and increase in HDL cholesterol (25.7%). Thus, the broth fermented with Zymomonas mobilis regulated the intestinal transit, but did not improve the lipid profile, while the without cells broth showed a better lipid profile.

A novel role of oxytocin: Oxytocin-induced well-being in humans

We review the involvement of a small molecule, oxytocin, in various effects of physical stimulation of somatosensory organs, mindfulness meditation, emotion and fragrance on humans, and then propose a hypothesis that complex human states and behaviors, such as well-being, social bonding, and emotional behavior, are explained by oxytocin. We previously reported that oxytocin can induce pain relief and described the possibility how oxytocin in the dorsal horn and/or the dorsal root ganglion relieves joint and muscle pain. In the present article, we expand our research target from the physical analgesic effects of oxytocin to its psychologic effects to upregulate well-being and downregulate stress and anxiety. For this purpose, we propose a “hypothalamic-pituitary-adrenal (HPA) axis-oxytocin model” to explain why mindfulness meditation, placebo, and fragrance can reduce stress and anxiety, resulting in contentment. This new proposed model of HPA axis-oxytocin in the brain also provides a target to address other questions regarding emotional behaviors, learning and memory, and excess food intake leading to obesity, aimed at promoting a healthy life.

Rethinking placebo in psychiatry: the range of placebo effects

This article, the first of two on placebo effects, provides a broad overview of placebo in the field of medicine. A brief conceptual history is followed by some basic facts about placebos. Problems of definition are identified. Additive and non-additive models of treatment effects, and problems of measurement of placebo effects are described. The role of placebo in the pharmacotherapy of depression and complementary and alternative medicine is discussed. The ‘efficacy paradox’ (that placebo treatments can have larger effects than ‘evidence-based treatments’) is introduced. Finally, ethical issues are discussed.

From Bench to Bedside: Converting Placebo Research into Belief Activation

Research on the placebo effect contains important elements that can be harnessed to improve clinical care. This paper proposes a new term, "Belief Activation," to describe the deliberate use of placebo effect tools by both patients and clinicians to catalyze healing. Belief Activation includes, but is not limited to, maximizing patient and practitioner expectations, classical and social conditioning, spirituality and prayer/intention, therapeutic relationship, healing environments, and minimizing the nocebo effect. This paper demonstrates ways in which Belief Activation is a form of evidence-based medicine and seeks to translate knowledge from placebo research into medical practice.

What techniques might be used to harness placebo effects in non-malignant pain? A literature review and survey to develop a taxonomy

OBJECTIVES

Placebo effects can be clinically meaningful but are seldom fully exploited in clinical practice. This review aimed to facilitate translational research by producing a taxonomy of techniques that could augment placebo analgesia in clinical practice.

DESIGN

Literature review and survey.

METHODS

We systematically analysed methods which could plausibly be used to elicit placebo effects in 169 clinical and laboratory-based studies involving non-malignant pain, drawn from seven systematic reviews. In a validation exercise, we surveyed 33 leading placebo researchers (mean 12 years’ research experience, SD 9.8), who were asked to comment on and add to the draft taxonomy derived from the literature.

RESULTS

The final taxonomy defines 30 procedures that may contribute to placebo effects in clinical and experimental research, proposes 60 possible clinical applications and classifies procedures into five domains: the patient’s characteristics and belief (5 procedures and 11 clinical applications), the practitioner’s characteristics and beliefs (2 procedures and 4 clinical applications), the healthcare setting (8 procedures and 13 clinical applications), treatment characteristics (8 procedures and 14 clinical applications) and the patientâ€"practitioner interaction (7 procedures and 18 clinical applications).

CONCLUSION

The taxonomy provides a preliminary and novel tool with potential to guide translational research aiming to harness placebo effects for patient benefit in practice.

Possible contribution of quantum-like correlations to the placebo effect: consequences on blind trials

Background

Factors that participate in the biological changes associated with a placebo are not completely understood. Natural evolution, mean regression, concomitant procedures and other non specific effects are well-known factors that contribute to the “placebo effect”. In this article, we suggest that quantum-like correlations predicted by a probabilistic modeling could also play a role.

Results

An elementary experiment in biology or medicine comparing the biological changes associated with two placebos is modeled. The originality of this modeling is that experimenters, biological system and their interactions are described together from the standpoint of a participant who is uninvolved in the measurement process. Moreover, the small random probability fluctuations of a “real” experiment are also taken into account. If both placebos are inert (with only different labels), common sense suggests that the biological changes associated with the two placebos should be comparable. However, the consequence of this modeling is the possibility for two placebos to be associated with different outcomes due to the emergence of quantum-like correlations.

Conclusion

The association of two placebos with different outcomes is counterintuitive and this modeling could give a framework for some unexplained observations where mere placebos are compared (in some alternative medicines for example). This hypothesis can be tested in blind trials by comparing local vs. remote assessment of correlations.

Predictors of positive opinion about Bach Flower Remedies in adults from three Latin-American countries: An exploratory study

The current study aimed to determine if positive opinions about BFR interacts with spirituality in adults from three Latin-American countries using a CHAID algorithm. Participants were 703 adults from Cuba (n = 319), Costa Rica (n = 252) and Chile (n = 132).

PREDICTORS

demographic data, received information, received treatment, spirituality, dispositional optimism and willingness to use a placebo intervention were measured and analyzed. A supervised classification which included a training phase (n = 423) and a test phase (n = 280) was employed. Received information about BFR, spirituality and education were selected as significant predictors of the positive opinion about BFR (>90% of correct classifications).

Does the model of additive effect in placebo research still hold true? A narrative review

Personalised and contextualised care has been turned into a major demand by people involved in healthcare suggesting to move toward person-centred medicine. The assessment of person-centred medicine can be most effectively achieved if treatments are investigated using ‘with versus without’ person-centredness or integrative study designs. However, this assumes that the components of an integrative or person-centred intervention have an additive relationship to produce the total effect. Beecher’s model of additivity assumes an additive relation between placebo and drug effects and is thus presenting an arithmetic summation. So far, no review has been carried out assessing the validity of the additive model, which is to be questioned and more closely investigated in this review.

Initial searches for primary studies were undertaken in July 2016 using Pubmed and Google Scholar. In order to find matching publications of similar magnitude for the comparison part of this review, corresponding matches for all included reviews were sought.

A total of 22 reviews and 3 clinical and experimental studies fulfilled the inclusion criteria. The results pointed to the following factors actively questioning the additive model: interactions of various effects, trial design, conditioning, context effects and factors, neurobiological factors, mechanism of action, statistical factors, intervention-specific factors (alcohol, caffeine), side-effects and type of intervention.

All but one of the closely assessed publications was questioning the additive model. A closer examination of study design is necessary. An attempt in a more systematic approach geared towards solutions could be a suggestion for future research in this field.

A sham-controlled randomized trial of adjunctive light therapy for non-seasonal depression

BACKGROUND

The aim of the study was to examine the efficacy and safety of morning bright light therapy (BLT) in the treatment of patients with a current major depressive episode (MDE) in bipolar and unipolar disorder without a seasonal pattern. It was a randomized, sham-controlled trial.

METHODS

Adults, ages 18-70 years were randomized to treatment either with BLT or a sham negative ion generator (as a placebo control). The subjects were required to be on a stable and therapeutic dose of psychotropic medication for at least 4 weeks prior to enrollment and their treatment had to be insufficiently effective. Their clinical state was monitored at the baseline and at the end of treatment. The Hamilton Depression Rating Scale-21 items (HDRS-21), Montgomery-Asberg Depression Rating Scale (MADRS), Beck Depression Inventory (BDI-II), Clinical Global Impression-Severity (CGI-S) and Patient Global Impression (PGI) were used. The results were analyzed with an intention-to-treat (ITT) analysis.

RESULTS

Ninety-five patients were enrolled (50 diagnosed with bipolar disorder and 45 with unipolar depression). Fifty-two patients were randomized to treatment with BLT and forty-three were in the placebo group (ITT population). Eighty-three subjects completed the study. There were 12 dropouts (5 in the light group and 7 in the placebo group). After 14 days of treatment, a significant improvement was found in all groups (p<0.001). The subjects treated with BLT did not significantly differ in terms of improvement in HDRS-21 scores at the endpoint when compared to patients treated with placebo (p=0.2). However, further analysis demonstrated significantly higher response (50% v. 27.9%, p=0.02) and remission rates (28.8% v. 11.6%, p=0.04) among patients treated with morning BLT when compared to placebo group. It should be noted that in the population of drug-resistant patients, BLT was more efficacious than placebo. There were no statistically significant differences between unipolar and bipolar disorders (p=0.4).

CONCLUSION

Although overall improvement in HDRS-21 scores were not superior in the BLT group, both response and remission rates were significantly higher among patients treated with BLT relative to those receiving the sham intervention. BLT was also more efficacious than placebo in the population of patients with drug-resistant depression. Further studies to define the subpopulation of patients with non-seasonal depression who may benefit the most from BLT are needed.

Individualized Homeopathy: A Consideration of Its Relationship to Psychotherapy

OBJECTIVES

The benefit and potential mechanisms of action of homeopathy have long been debated. Almost entirely neglected has been the study of individualized homeopathy (IH) as a form of psychotherapy, which incorporates factors that are common to most therapies while using processes that are specific to IH.

METHODS

Recent research into the therapeutic components of IH is reviewed; similarities and differences between IH and other forms of psychotherapy are also described.

RESULTS

IH includes elements found in humanistic therapy and narrative medicine and additionally incorporates idiographic material in treatment selection. It is structured in a manner that takes maximum advantage of the components of the placebo effect, which could further expand its effectiveness beyond those conditions thought usually amenable to psychotherapy.

CONCLUSIONS

It is possible that IH entails specific psychotherapeutic processes in addition to possible therapeutic action of the homeopathic remedy, but the relative contributions of each remain to be determined. Suggestions are given for future research.

Measuring nonspecific factors in treatment: item banks that assess the healthcare experience and attitudes from the patient's perspective

PURPOSE

Nonspecific factors that accompany healthcare treatments, such as patients' attitudes and expectations, are important parts of the experience of care and can influence outcomes. However, no precise, concise, and generalizable instruments to measure these factors exist. We report on the development and calibration of new item banks, titled the Healing Encounters and Attitudes Lists (HEAL), that assess nonspecific factors across a broad range of treatments and conditions.

METHODS

The instrument development methodology of the Patient-Reported Outcomes Measurement Information System (PROMIS(®)) was used. Patient focus groups and clinician interviews informed our HEAL conceptual model. Literature searches of eight databases yielded over 500 instruments and resulted in an initial item pool of several thousand items. After qualitative item analysis, including cognitive interviewing, 296 items were included in field testing. The calibration sample included 1657 respondents, 1400 obtained through an Internet panel and 257 from conventional and integrative medicine clinics. Following exploratory and confirmatory factor analyses, the HEAL item banks were calibrated using item response theory.

RESULTS

The final HEAL item banks were Patient-Provider Connection (57 items), Healthcare Environment (25 items), Treatment Expectancy (27 items), Positive Outlook (27 items), and Spirituality (26 items). Short forms were also developed from each item bank. A six-item short form, Attitudes toward Complementary and Alternative Medicine (CAM), was also created.

CONCLUSIONS

HEAL item banks provided substantial information across a broad range of each construct. HEAL item banks showed initial evidence of predictive and concurrent validity, suggesting that they are suitable for measuring nonspecific factors in treatment.

The placebo effect in asthma

The placebo effect is a complex phenomenon occurring across a variety of clinical conditions. While much placebo research has been conducted in diseases defined by self-report such as depression, chronic pain, and irritable bowel syndrome (IBS), asthma has been proposed as a useful model because of its easily measured objective outcomes. Studies examining the placebo response in asthma have not only contributed to an understanding of the mechanisms behind the placebo response but also shed an interesting light on the current treatment and diagnosis of asthma. This paper will review current literature on placebos in general and specifically on the placebo response in asthma. It focuses on what we know about the mechanisms behind the placebo effect, whether there is a specific portion of the population who responds to placebos, which patient outcomes are influenced by the placebo effect, and whether the effect can be augmented.

Randomised controlled trials may underestimate drug effects: balanced placebo trial design

Background

It is an inherent assumption in randomised controlled trials that the drug effect can be estimated by subtracting the response during placebo from the response during active drug treatment.

Objective

To test the assumption of additivity. The primary hypothesis was that the total treatment effect is smaller than the sum of the drug effect and the placebo effect. The secondary hypothesis was that non-additivity was most pronounced in participants with large placebo effects.

Methods

We used a within-subject randomised blinded balanced placebo design and included 48 healthy volunteers (50% males), mean (SD) age 23.4 (6.2) years. Experimental pain was induced by injections of hypertonic saline into the masseter muscle. Participants received four injections with hypertonic saline along with lidocaine or matching placebo in randomised order: A: received hypertonic saline/told hypertonic saline; B: received hypertonic saline+lidocaine/told hypertonic saline; C: received hypertonic saline+placebo/told hypertonic saline+pain killer; D: received hypertonic saline+lidocaine/told hypertonic saline+pain killer. The primary outcome measure was the area under the curve (AUC, mm²) of pain intensity during injections.

Results

There was a significant difference between the sum of the drug effect and the placebo effect (mean AUC 6279 mm² (95% CI, 4936–7622)) and the total treatment effect (mean AUC 5455 mm² (95% CI, 4585–6324)) (P = 0.049). This difference was larger for participants with large versus small placebo effects (P = 0.015), and the difference correlated significantly with the size of the placebo effect (r = 0.65, P = 0.006).

Conclusion

Although this study examined placebo effects and not the whole placebo response as in randomised controlled trials, it does suggest that the additivity assumption may be incorrect, and that the estimated drug effects in randomised controlled trials may be underestimated, particularly in studies reporting large placebo responses. The implications for randomised controlled trials and systematic reviews need to be discussed.

Placebo responses on cardiovascular, gastrointestinal, and respiratory organ functions

It is widely acknowledged that placebo responses are accompanied by physiological changes in the central nervous system, but little is known about placebo responses on end organ functions. The present chapter aims to fill this gap by reviewing the literature on peripheral placebo responses. Overall, there is a wide range of placebo and nocebo responses on various organ functions of the cardiovascular, the gastrointestinal system, and the respiratory system. Most of these studies used expectation paradigms to elicit placebo and nocebo responses. Expectations can affect heart rate, blood pressure, coronary diameter, gastric motility, bowel motility, and lung function. Classical conditioning can induce placebo respiratory depression after prior exposure to opioid drugs, and habitual coffee drinkers show physiological arousal in response to coffee-associated stimuli. Similar to findings in placebo pain research, peripheral placebo responses can be target specific. The autonomic nervous system is a likely candidate to mediate peripheral placebo responses. Further studies are necessary to identify the brain mechanisms and pathways involved in peripheral placebo responses.

The placebo effect in allergen-specific immunotherapy trials

BACKGROUND

Double-blind, placebo-controlled (DBPC) trials are the gold standard for demonstrating clinical efficacy and tolerability. The placebo effect, although an important feature in placebo-controlled studies, has never been systematically investigated in allergen-specific immunotherapy (SIT) studies. This study was performed to examine the placebo response in SIT trials that employed a baseline observational period and two treatment years using a symptom-medication-score (SMS) as the primary endpoint.

METHODS

The placebo effect was evaluated in six DBPC SIT studies (five studies using subcutaneous SIT (SCIT) and one sublingual (SLIT)), two grass, two birch and two house dust mite (HDM) SIT, including a total of 472 adult patients treated with a placebo. The results were reported as changes from baseline of the SMS area under the curve after two years of perennial placebo therapy during the respective evaluation periods. Pollen counts and IgG4 levels were additionally analysed.

RESULTS

Subcutaneously treated placebo patients displayed a marked decrease in the SMS. The mean placebo effect in the SCIT trials with comparable allergen exposure was up to 41% in the second treatment year and, in contrast, reached only 1% in the SLIT trial. Allergen exposure had an inverse influence on the placebo effect. No changes from baseline in allergen specific IgG4 antibodies were observed in the placebo-treated patients.

CONCLUSIONS

SIT studies display a significant placebo effect, mainly observed in subcutaneous immunotherapy, with high variability depending on the route of application and allergen exposure. Our findings indicate the differential role of the placebo effect in SIT efficacy depending on the route of administration and pollen exposure.

Mechanisms of the placebo response in pain in osteoarthritis

INTRODUCTION

Administration of a placebo associates with symptomatic improvement in many conditions--the so-called placebo response. In this review we explain the concept of placebo response, examine the data that supports existence in osteoarthritis (OA), and discuss its possible mechanisms and determinants.

METHODS

A Pubmed literature search was carried out. Key articles were identified, and their findings discussed in a narrative review.

RESULTS

Pain, stiffness, self-reported function and physician-global assessment in OA clearly improve in response to placebo. However, more objective measures such as quadriceps strength and radiographic progression appear less responsive. Although not directly studied in OA, contextual effects, patient expectation and conditioning are believed to be the main mechanisms. Neurotransmitter changes that mediate placebo-induced analgesia include increased endogenous opioid levels, increased dopamine levels, and reduced levels of cholecystokinin. Almost all parts of the brain involved in pain processing are influenced during placebo-induced analgesia. Determinants of the magnitude of placebo response include the patient-practitioner interaction, treatment response expectancy, knowledge of being treated, patient personality traits and placebo specific factors such as the route and frequency of administration, branding, and treatment costs.

CONCLUSION

Clearer understanding of the neurobiology of placebo response validates its existence as a real phenomenon. Although routine administration of placebo for symptomatic improvement is difficult to justify, contextual factors that enhance treatment response should be employed in the management of chronic painful conditions such as OA where available treatments have only modest efficacy.

Naltrexone may block euphoria-like placebo effect

Naltrexone is a first-line treatment for alcohol use disorders in North America and Europe. It was prescribed to a 63-year-old patient in order to help control amounts of alcohol consumed per drinking occasion. The patient experienced a paradoxical, but consistent side effect of feeling inebriated each time he took naltrexone. In order to investigate this phenomenon we administered naltrexone and a placebo in a randomised double-blind fashion. The patient exhibited a 'high-like' response to all placebo capsules and a decrease in the subjectively perceived euphoria shortly after ingestion of naltrexone. Given that this placebo effect could be mediated via opioid receptors we suggest that this case illustrates the ability of naltrexone to eliminate the placebo effect. This feature of naltrexone, upon further investigation, might be used in randomised clinical trials in addition to or as an alternative to a placebo.

An exploration of the relationship between placebo and homeopathy and the implications for clinical trial design

Placebo appears to be a real neurobiological phenomenon that has evolved through the selection pressure to be able to heal ourselves. The complex language and social structures of humans means that we can attribute meaning to therapeutic encounters with culturally sanctioned authority figures and we can use our attachment to such figures to generate hope for recovery. Different mechanisms may be involved in the neurobiological aspect of placebo including anxiety, learning, conditioning as well as individual genetic variation. Examination of the published work shows that while some trials do seem to indicate a specific mode of action for homeopathic remedies other trials do not and this is an issue that needs to be addressed at the trial design stage. A clinical trial that includes both a placebo group and a non-participating control arm is the most powerful design for separating the non-specific and polymorphic placebo effect from the specific effects of trial medication. The control variables in a trial of homeopathic medication should also include the process of consultation as this may assume a meaning for the individual that can also be associated with a placebo effect.

Morning light therapy for juvenile depression and severe mood dysregulation: study protocol for a randomized controlled trial

BACKGROUND

The prevalence of depression in young people is increasing. The predominant co-morbidities of juvenile depression include sleep disturbances and persistent problems with the sleep-wake rhythm, which have shown to influence treatment outcomes negatively. Severe mood dysregulation is another condition that includes depressive symptoms and problems with the sleep-wake rhythm. Patients with severe mood dysregulation show symptoms of depression, reduced need for sleep, and disturbances in circadian functioning which negatively affect both disorder-specific symptoms and daytime functioning. One approach to treating both depression and problems with the sleep-wake rhythm is the use of light therapy. Light therapy is now a standard therapy for ameliorating symptoms of seasonal affective disorder and depression in adults, but has not yet been investigated in children and adolescents. In this trial, the effects of 2 weeks of morning bright-light therapy on juvenile depression and severe mood dysregulation will be evaluated.

METHODS/DESIGN

A total of 60 patients with depression, aged between 12 and 18 years, in some cases presenting additional symptoms of affective dysregulation, will be included in this trial. Morning bright-light therapy will be implemented for 2 weeks (10 sessions of 45 minutes each), either with 'active' light (10,000 lux) or 'inactive' light (100 lux). A comprehensive test battery will be conducted before and after treatment and at follow-up 3 weeks later, to assess depression severity, sleep, and attention parameters. Melatonin levels will be measured by assessing the Dim Light Melatonin Onset.

DISCUSSION

In this pilot study, the use of morning bright-light therapy for juvenile depression and severe mood dysregulation shall be evaluated and discussed.

TRIALS REGISTRATION

Current Controlled Trials ISRCTN89305231.

Local biologies and HIV/AIDS in highlands Papua, Indonesia

The province of Papua, Indonesia has one of the fastest growing rates of HIV infection in Asia. Within volatile political conditions, HIV has reached generalized epidemic status for indigenous Papuans. This article explores the merits of using the concept of local biologies as an analytic tool to assess the range of factors which affect a local pattern of untreated HIV and rapid onset of AIDS. A research team conducted 32 in-depth interviews with HIV-positive indigenous persons and 15 interviews with health care workers in urban and peri-urban sites in the central highlands region. The results show fear of gossip and stigmatization, regional political conditions and gaps in care interweave to create local biological conditions of evasion of care and rapid onset of AIDS. The normative emphasis in contemporary scholarship on stigma as shaping subjective responses to HIV needs to be complemented by a full assessment of the physiological impact of health services, and the ways political conditions trickle down and mediate local biological patterns. The concept of local biologies is highly effective for explaining the full scope of possible factors affecting the intersection of social and physical realms for HIV-positive persons.

Widespread use of pure and impure placebo interventions by GPs in Germany

AIM

To collect data on the use of placebo interventions by GPs in Germany.

METHODS

A questionnaire was mailed to 400 randomly selected GPs in Bavaria. Non-responders were reminded by telephone after 4 weeks and were given a second copy of the questionnaire after a further 3 weeks.

RESULTS

In all, 208 completed questionnaires were returned. The majority of GPs (88%) have used a placebo at least once in their practice; 45% have used pure placebos, such as saline injections and sugar pills, at least once last year; the median frequency of use was 5 [interquartile range (IQR), 2-10]. The use of impure placebos during the past year was more common: 76% of GPs have used impure placebos, i.e. medical interventions that have pharmacological or physical activity but have no intrinsic effect (e.g. pharmacological or physical action) on the patient's disease or its symptoms, with a median frequency of 20 times per year (IQR, 10-50). The main reason for the use of placebo was a possible psychological effect, followed by the expectation of patients to receive a treatment. For the majority of GPs placebo interventions were ethically justified if they were used for a possible psychological effect.

CONCLUSIONS

Placebo interventions are a widely accepted part of medical treatment in German general practices and are used primarily for their psychological effects. Impure placebos are used much more frequently than pure placebos.

Placebo-controlled trials in relapsing–remitting multiple sclerosis: are they still needed?

Placebo-controlled clinical trials are an important tool to verify the efficacy of therapeutic approaches. During recent years, many trials have been conducted into relapsing–remitting multiple sclerosis, resulting in a variety of treatment options considered effective based on prospective, randomized controlled trials with masked outcome assessment in a representative population of patients (class I evidence). Accordingly, treatment is recommended because the benefit of treatment outweighs the potential risks (level A recommendation), whereas no treatment or delay of treatment may potentially harm patients. Placebo-controlled trials seem to be outdated in relapsing–remitting multiple sclerosis because they: cannot predict where a new treatment is placed in relation to the already established therapies, lead to the recruitment of inactive and nonrepresentative patient populations, delay the registration process due to slow recruitment, change the genetic background of study populations due to a shift of clinical trials to Asian countries and are unethical.

Placebo mechanisms across different conditions: from the clinical setting to physical performance

Although the great increase in interest in the placebo phenomenon was spurred by the clinical implications of its use, the progressive elucidation of the neurobiological and pharmacological mechanisms underlying the placebo effect also helps cast new light on the relationship between mind (and brain) and body, a topic of foremost philosophical importance but also a major medical issue in light of the complex interactions between the brain on the one hand and body functions on the other. While the concept of placebo can be a general one, with a broad definition generally applicable to many different contexts, the description of the cerebral processes called into action in specific situations can vary widely. In this paper, examples will be given where physiological or pathological conditions are altered following the administration of an inert substance or verbal instructions tailored to induce expectation of a change, and explanations will be offered with details on neurotransmitter changes and neural pathways activated. As an instance of how placebo effects can extend beyond the clinical setting, data in the physical performance domain and implications for sport competitions will also be presented and discussed.