The placebo in practice: how to use it in clinical routine

Pain expectation and avoidance in the social context: an electrophysiological study

Contingent negative variation (CNV) is an informative electrophysiological measure of pain anticipation showing higher amplitudes when highly painful stimulation is expected while presenting lower amplitudes when low painful stimulation is expected. Two groups of participants were recruited: one group expected and received an electrical stimulation of different intensities while being alone in the room (i.e. without social context), while a second group performed the same experiment with an observer in the room (i.e. with social context). Lower pain ratings and slower reaction times were observed in the group with social context and these results were accompanied in this group by a lower amplitude in the early component of the CNV as well as a lower amplitude of the later component of the wave. These results show that CNV can be considered a precise measure of central elaboration of pain anticipation explaining both its perceptual and motor components.

'External timing' of placebo analgesia in an experimental model of sustained pain

BACKGROUND

Research on placebo analgesia commonly focuses on the impact of information about direction (i.e., increase or decrease of pain) and magnitude of the expected analgesic effect, whereas temporal aspects of expectations have received little attention so far. In a recent study, using short-lasting, low-intensity stimuli, we demonstrated that placebo analgesia onset is influenced by temporal information. Here, we investigate whether the same effect of temporal suggestions can be found in longer lasting, high-intensity pain in a Cold Pressor Test (CPT).

METHODS

Fifty-three healthy volunteers were allocated to one of three groups. Participants were informed that the application of an (inert-)cream would reduce pain after 5 min (P5) or 30 min (P30). The third group was informed that the cream only had hydrating properties (NE). All participants completed the CPT at baseline and 10 (Test 10) and 35 min (Test 35) following cream application. Percentage change in exposure time (pain tolerance) from baseline to Test 10 (Δ10) and to Test 35 (Δ35) and changes in heart rate (HR) during CPT were compared between the three groups.

RESULTS

Δ10 was greater in P5 than in NE and P30, indicating that analgesia was only present in the group that was expecting an early onset of analgesia. Δ35 was greater in P5 and P30 compared to NE, reflecting a delayed onset of analgesia in P30 and maintained analgesia in P5. HR differences between groups were not significant.

CONCLUSIONS

Our data suggest that 'externally timing' of placebo analgesia may be possible for prolonged types of pain.

SIGNIFICANCE

Research on placebo effects mainly focuses on the influence of information about direction (i.e., increase or decrease of pain) and magnitude (i.e., strong or weak) of the expected effect but ignores temporal aspects of expectations. In our study in healthy volunteers, the reported onset of placebo analgesia followed the temporal information provided. Such 'external timing' effects could not only aid the clinical use of placebo treatment (e.g., in open-label placebos) but also support the efficacy of active drugs.

The placebo effect in breath holding: a preliminary behavioral investigation

PURPOSE

This study seeks to evaluate effects of expectations and conditioning on dry breath holding.

METHODS

Sixty healthy volunteers were subdivided into 3 groups and were tested across 4 breath holding trials. Participants of the Control group (C) did not undergo any manipulation. Participants of the placebo (P) and nocebo (N) groups were told that they would inhale O2 (actually sham O2) or CO2 (actually sham CO2) along with opposite information that this would enhance or worsen their breath holding time, respectively. Opposite conditioning paradigms based on false visual feedback were employed to reinforce participants' positive (placebo) and negative (nocebo) beliefs.

RESULTS

The P group showed the greater increase in breath holding time from baseline to the last trial (p = 0.0001) and the longest breath holding time in the last trial compared to the C group (p = 0.02) and the N group (p = 0.0001). Additionally, in the last trial the P group showed a greater decrease in peripheral oxygen saturation (SpO2) as compared to the C group (p = 0.04) and the N group (p = 0.001). Heart rate (HR) was accelerated in the N group during breath holding (in comparison to the P group [p = 0.04] and C group [p = 0.04]).

CONCLUSIONS

Psychological components can affect behavioral and physiological parameters in breath holding. This study may inform future research about the role of placebo and nocebo effects for conditions in which critical functions are at play.

The Overactive Pelvic Floor (OPF) and Sexual Dysfunction. Part 2: Evaluation and Treatment of Sexual Dysfunction in OPF Patients

INTRODUCTION

The assessment of pelvic floor muscle (PFM) overactivity is part of a comprehensive evaluation including a detailed history (medical, gynecological history/antecedent), appraisal of the psychosocial contexts of the patient, as well as a musculoskeletal and a neurological examination.

OBJECTIVES

The aims of this article are to review (i) the assessment modalities evaluating pelvic floor function in women and men with disorders associated with an overactive pelvic floor (OPF), and (ii) therapeutic approaches to address OPF, with particular emphases on sexual pain and function.

METHODS

We outline assessment tools that evaluate psychological and cognitive states. We then review the assessment techniques to evaluate PFM involvement including digital palpation, electromyography, manometry, ultrasonography, and dynamometry, including an overview of the indications, efficacy, advantages, and limitations of each instrument. We consider each instrument's utility in research and in clinical settings. We next review the evidence for medical, physiotherapy, and psychological interventions for OPF-related conditions.

RESULTS

Research using these assessment techniques consistently points to findings of high PFM tone among women and men reporting disorders associated with OPF. While higher levels of evidence are needed, options for medical treatment include diazepam suppositories, botulinum toxin A, and other muscle relaxants. Effective psychological therapies include cognitive behavioral therapy, couple therapy, mindfulness, and educational interventions. Effective physiotherapy approaches include PFM exercise with biofeedback, electrotherapy, manual therapy, and the use of dilators. Multimodal approaches have demonstrated efficacy in reducing pain, normalizing PFM tone, and improving sexual function. Multidisciplinary interventions and an integrative approach to the assessment and management of OPF using a biopsychosocial framework are discussed.

CONCLUSION

Although the efficacy of various intervention approaches has been demonstrated, further studies are needed to personalize interventions according to a thorough assessment and determine the optimal combination of psychological, physical, and behavioral modalities. Padoa A, McLean, L, Morin M, et al. The Overactive Pelvic Floor (OPF) and Sexual Dysfunction. Part 2: Evaluation and Treatment of Sexual Dysfunction in OPF Patients. Sex Med 2021;9:76-92.

A design for process-outcome psychotherapy research in adolescents with Borderline Personality Pathology

Underage patients with Borderline Personality Pathology (BPP) are in need of specialised psychotherapeutic treatment. A handful of these treatments, including Adolescent Identity Treatment (AIT) and Dialectical Behavior Therapy for Adolescents (DBT-A), have been adapted for adolescent patients. Psychotherapy research has shown that the outcome of different psychotherapeutic approaches can be very similar despite conceptual and practical differences between the theoretical models. Therefore, to understand what really works in psychotherapy, it is necessary to investigate the psychotherapeutic process and its effects on the patient. This paper presents a study design for process-outcome research, integrating (1) a classical outcome design, comparing AIT and DBT-A in a non-inferiority trial assessing changes in psychosocial functioning at 12 months after baseline as primary outcome; and (2) a process research design, addressing multiple BPP and psychotherapy relevant factors. These factors include well-studied generic variables such as the psychotherapeutic alliance, more recent approaches such as video-based identification of significant therapeutic events, as well as more experimental approaches such as psychophysiological markers measured during the therapeutic sessions. The use of repeated measures and the methodological pluralism which includes event and micro-process analyses has been recommended for psychotherapy research aiming at a better understanding of the interplay of factors at work to narrow the gap between research and practice in this field.

Clinical relevance of contextual factors as triggers of placebo and nocebo effects in musculoskeletal pain

Placebo and nocebo effects are embodied psycho-neurobiological responses capable of modulating pain and producing changes at different neurobiological, body at perceptual and cognitive levels. These modifications are triggered by different contextual factors (CFs) presented in the therapeutic encounter between patient and healthcare providers, such as healing rituals and signs. The CFs directly impact on the quality of the therapeutic outcome: a positive context, that is a context characterized by the presence of positive CFs, can reduce pain by producing placebo effects, while a negative context, characterized by the presence of negative CFs, can aggravate pain by creating nocebo effects. Despite the increasing interest about this topic; the detailed study of CFs as triggers of placebo and nocebo effects is still lacked in the management of musculoskeletal pain.

Increasing evidence suggest a relevant role of CFs in musculoskeletal pain management. CFs are a complex sets of internal, external or relational elements encompassing: patient’s expectation, history, baseline characteristics; clinician’s behavior, belief, verbal suggestions and therapeutic touch; positive therapeutic encounter, patient-centered approach and social learning; overt therapy, posology of intervention, modality of treatment administration; marketing features of treatment and health care setting. Different explanatory models such as classical conditioning and expectancy can explain how CFs trigger placebo and nocebo effects. CFs act through specific neural networks and neurotransmitters that were described as mediators of placebo and nocebo effects.

Available findings suggest a relevant clinical role and impact of CFs. They should be integrated in the clinical reasoning to increase the number of treatment solutions, boosts their efficacy and improve the quality of the decision-making. From a clinical perspective, the mindful manipulation of CFs represents a useful opportunity to enrich a well-established therapy in therapeutic setting within the ethical border. From a translational perspective, there is a strong need of research studies on CFs close to routine and real-world clinical practice in order to underline the uncertainty of therapy action and help clinicians to implement knowledge in daily practice.

Drug versus placebo randomized controlled trials in neonates: A review of ClinicalTrials.gov registry

BACKGROUND

Despite specific initiatives and identified needs, most neonatal drugs are still used off-label, with variable dosage administrations and schedules. In high risk preterm and term neonates, drug evaluation is challenging and randomized controlled trials (RCT) are difficult to conduct and even more is the use of a placebo, required in the absence of a reference validated drug to be used as comparator.

METHODS

We analyzed the complete ClinicalTrials.gov registry 1) to describe neonatal RCT involving a placebo, 2) to report on the medical context and ethical aspects of placebo use.

RESULTS

Placebo versus drug RCT (n = 146), either prevention trials (n = 57, 39%) or therapeutic interventions (n = 89, 61%), represent more than a third of neonatal trials registered in the National Institute of Health clinical trial database (USA) since 1999. They mainly concerned preterm infants, evaluating complications of prematurity. Most trials were conducted in the USA, were single centered, and funded by non-profit organizations. For the three top drug trials evaluating steroids (n = 13, 9.6%), erythropoietin (EPO, n = 10, 6.8%) and nitric oxide (NO, n = 9, 6.2%), the objectives of the trial and follow-up were analyzed in more details.

CONCLUSION

Although a matter of debate, the use of placebo should be promoted in neonates to evaluate a potential new treatment, in the absence of reference drug. Analysis of the trials evaluating steroids showed that long-term follow-up of exposed patients, although required by international guidelines, is frequently missing and should be planned to collect additional information and optimize drug evaluation in these high-risk patients.

Who are the users of a traditional Chinese sanfu acupoint herbal patching therapy in China?: A cross-sectional survey

Sanfu acupoint herbal patching (SAHP) is a unique traditional Chinese medicine therapy, which has become popular for preventing acute attack of respiratory diseases such as asthma and chronic obstructive pulmonary disease, in many regions of mainland China. However, the knowledge about its users is lacking, especially the characteristics of the users and their experience and perspectives.To investigate the demographics of users, conditions for its use and the previous experience of SAHP, as well as users' perspectives to provide baseline information for its practice.A cross-sectional consecutive-sample survey was conducted at outpatient departments from 3 traditional Chinese medicine hospitals in northern China. Each participant completed a questionnaire, after informed consent. Data description and analyses were done using SPSS 20.0.Among 949 SAHP users from 3 hospitals, female was predominant (n = 592; 62.4%), aged from 2 to 96 years (median = 52 years). 64.7% (380/587) of regular users have applied consecutively for 3 years or over, and the self-perceived satisfaction rates of respiratory diseases were from 45.9% to 77.7%. Positive attitude toward traditional Chinese medicine was the top reason for choosing SAHP. 42.4% of users held a motivation of being cured by SAHP and with great outcome expectancy on SAHP (70.8%).SAHP users were mainly female adults or elderly population; more than half were regular users, who predominantly used SAHP for various chronic respiratory diseases during their stable stage. The majority of users expressed satisfaction to previous SAHP for their respiratory diseases. 42.4% of users held a motivation of being cured by SAHP and with great outcome expectancy on SAHP (70.8%). The findings from this survey deserve further clinical trials for their clinical effectiveness.

Physical Therapy in the Treatment of Central Pain Mechanisms for Female Sexual Pain

INTRODUCTION

The complexity of female sexual pain requires an interdisciplinary approach. Physical therapists trained in pelvic health conditions are well positioned to be active members of an interdisciplinary team addressing the assessment and treatment of female sexual pain. Changes within physical therapy practice in the last ten years have resulted in significant utilization of pelvic floor muscle relaxation and manual therapy techniques to address a variety of pelvic pain conditions, including female sexual pain. However, sexual pain is a complex issue giving credence to the necessity of addressing all of the drivers of the pain experience- biological, psychological and social.

AIM

This review aims to reconcile current pain science with a plan for integrating a biopsychosocial approach into the evaluation and subsequent treatment for female sexual pain for physical therapists.

METHODS

A literature review of the important components of skilled physical therapy interventions is presented including the physical examination, pain biology education, cognitive behavioral influences in treatment design, motivational interviewing as an adjunct to empathetic practice, and the integration of non-threatening movement and mindfulness into treatment.

MAIN OUTCOME MEASURE

A single case study is used to demonstrate the biopsychosocial framework utilized in this approach.

RESULTS

Appropriate measures for assessing psychosocial factors are readily available and inform a reasoned approach for physical therapy design that addresses both peripheral and central pain mechanisms. Decades of research support the integration of a biopsychosocial approach in the treatment of complex pain, including female sexual pain.

CONCLUSION

It is reasonable for physical therapists to utilize evidence based strategies such as CBT, pain biology education, Mindfulness Based Stress Reduction (MBSR), yoga and imagery based exercises to address the biopsychosocial components of female sexual pain.

Different contexts, different pains, different experiences

Pain is an ambiguous perception: the same pain stimulation can be perceived differently in different contexts, producing different experiences, ranging from mild to unbearable pain. It can be even experienced as a rewarding sensation within the appropriate context. Overall, placebo and nocebo effects appear to be very good models to understand how the psychosocial context modulates the experience of pain. In this review, we examine the effects of different contexts on pain, with a specific focus on the neurobiological mechanisms. Positive and rewarding contexts inform the patients that an effective treatment is being delivered and are capable of producing pain relief through the activation of specific systems such as opioids, cannabinoids and dopamine. Conversely, a negative context can produce pain exacerbation and clinical worsening through the modulation of different systems, such as the activation of cholecystokinin and the deactivation of opioids and dopamine. In addition, when a therapy is delivered unbeknownst to the patient, its effects are reduced. A better understanding of the neurobiological underpinnings of the context-pain interaction is a challenge both for future pain research and for good clinical practice.

Hawthorne effect with transient behavioral and biochemical changes in a randomized controlled sleep extension trial of chronically short-sleeping obese adults: implications for the design and interpretation of clinical studies

OBJECTIVE

To evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.

DESIGN

Subjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.

SETTING

Outpatient.

PATIENTS

Obese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.

INTERVENTION

Non-pharmacological sleep extension.

MEASUREMENTS

Sleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.

RESULTS

Prior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.

LIMITATIONS

Relatively small sample size.

CONCLUSIONS

Improvements in biochemical and behavioral parameters between screening and randomization changed the "true" study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the "Hawthorne effect", according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00261898.

The effects of placebos and nocebos on physical performance

In this chapter we present and discuss recent studies on the mechanisms underlying placebo and nocebo effects in physical performance, showing how expectations and both pharmacological and nonpharmacological preconditioning procedures can be very effective in inducing placebo responses, with important implications for sport competitions. Furthermore, we place these findings within the biological model of central governor of fatigue, whose main goal is to protect our body from damage. A crucial aspect of this emerging field of placebo studies is related to the limit beyond which these procedures can be called doping in all respects.

Topiramate treatment for alcoholic outpatients recently receiving residential treatment programs: a 12-week, randomized, placebo-controlled trial

BACKGROUND

Initiation of a relapse prevention medication is crucial at the end of alcohol detoxification. This study aimed to examine the efficacy and safety of topiramate for alcoholism in patients receiving a residential treatment program of alcohol detoxification and post-acute treatment.

METHODS

This was a 12-week, randomized, double-blind, placebo-controlled trial of topiramate for alcoholism in patients receiving a residential treatment program. Individuals with DSM-IV alcohol dependence with minimal withdrawal were enrolled. Participants were randomly assigned to receive either 100-300 mg/day of topiramate or placebo. Primary outcomes were given as percentages of heavy drinking days and time to first day of heavy drinking. Other drinking outcomes, craving, and health-related quality of life were evaluated.

RESULTS

A total of 106 participants were randomized to receive topiramate (n=53) or placebo (n=53). Twenty-eight participants of the topiramate group (52.8%) and 25 participants of the placebo group (47.2%) completed the study. Averaged over the trial period, there was no significant difference between groups on the mean percentages of heavy drinking days [1.96 (-1.62 to 5.54), p=.28]. Log rank survival analysis found no difference of time to first day of heavy drinking between topiramate and placebo groups (61.8 vs. 57.5 days, respectively; χ(2)=0.61, d.f.=1, p=.81). Other secondary outcomes were not significantly different between groups.

CONCLUSIONS

By using a conservative model for data analysis, we could not detect the effectiveness of topiramate in this particular population. As the sensitivity analysis showed a trend of its benefit, further studies in larger sample sizes are still warranted.

Trigeminal nerve stimulation in major depressive disorder: acute outcomes in an open pilot study

Most patients with major depressive disorder (MDD) do not recover with initial pharmacotherapy, and many pursue combination treatments. Combining a medication with neuromodulation offers an alternative to purely pharmacologic strategies. In prior open and double-blind controlled trials for drug-resistant epilepsy, adjunctive external trigeminal nerve stimulation (eTNS) was found to be safe and well tolerated, to significantly reduce seizures, and to be associated with an improvement in depressive symptoms. Here, we present a comprehensive description of the first open pilot investigation in MDD. In this 8-week trial, eleven adults with unipolar MDD received nightly stimulation (V(1) branch). All entered with moderate to severe symptom levels despite at least two antidepressant medication trials in this episode. All the eleven adults completed the acute trial, without serious adverse events. Symptoms of depression improved significantly, whether assessed with clinician- or self-rated scales (all p < 0.01; effect sizes d 1.0-1.8), as did quality of life (p < 0.02). Four of the 11 achieved remission. These improvements from nightly adjunctive eTNS in treatment-resistant depression merit replication under double-blind conditions.