Do health education initiatives assist socioeconomically disadvantaged populations? A systematic review and meta-analyses

BACKGROUND

Health education interventions are considered critical for the prevention and management of conditions of public health concern. Although the burden of these conditions is often greatest in socio-economically disadvantaged populations, the effectiveness of interventions that target these groups is unknown. We aimed to identify and synthesize evidence of the effectiveness of health-related educational interventions in adult disadvantaged populations.

METHODS

We pre-registered the study on Open Science Framework https://osf.io/ek5yg/ . We searched Medline, Embase, Emcare, and the Cochrane Register from inception to 5/04/2022 to identify studies evaluating the effectiveness of health-related educational interventions delivered to adults in socio-economically disadvantaged populations. Our primary outcome was health related behaviour and our secondary outcome was a relevant biomarker. Two reviewers screened studies, extracted data and evaluated risk of bias. Our synthesis strategy involved random-effects meta-analyses and vote-counting.

RESULTS

We identified 8618 unique records, 96 met our criteria for inclusion - involving more than 57,000 participants from 22 countries. All studies had high or unclear risk of bias. For our primary outcome of behaviour, meta-analyses found a standardised mean effect of education on physical activity of 0.05 (95% confidence interval (CI) = -0.09-0.19), (5 studies, n = 1330) and on cancer screening of 0.29 (95% CI = 0.05-0.52), (5 studies, n = 2388). Considerable statistical heterogeneity was present. Sixty-seven of 81 studies with behavioural outcomes had point estimates favouring the intervention (83% (95% CI = 73%-90%), p < 0.001); 21 of 28 studies with biomarker outcomes showed benefit (75% (95%CI = 56%-88%), p = 0.002). When effectiveness was determined based on conclusions in the included studies, 47% of interventions were effective on behavioural outcomes, and 27% on biomarkers.

CONCLUSIONS

Evidence does not demonstrate consistent, positive impacts of educational interventions on health behaviours or biomarkers in socio-economically disadvantaged populations. Continued investment in targeted approaches, coinciding with development of greater understanding of factors determining successful implementation and evaluation, are important to reduce inequalities in health.

Communicating with children about 'everyday' pain and injury: A Delphi study

BACKGROUND

'Everyday' pain experiences are potentially critical in shaping our beliefs and behaviours around injury and pain. Influenced by social, cultural and environmental contexts, they form the foundation of one's understanding of pain and injury that is taken into adulthood. How to best communicate to young children about their everyday pain experiences, in order to foster adaptive beliefs and behaviours, is unknown.

METHODS

In this Delphi survey, we sought expert opinion on the key messages and strategies that parents/caregivers can consider when communicating with young children (aged 2-7 years) about 'everyday' pain that is most likely to promote recovery, resilience and adaptive pain behaviours. Eighteen experts participated including specialists in paediatric pain, trauma, child development, and psychology; educators and parents. The survey included three rounds.

RESULTS

Response rate was over 88%. Two hundred fifty-three items were raised; 187 reached 'consensus' (≥80% agreement among experts). Key messages that the experts agreed to be 'very important' were aligned with current evidence-based understandings of pain and injury. Strategies to communicate messages included parent/caregiver role-modelling, responses to child pain, and discussion during and/or after a painful experience. Other key themes included promoting emotional development, empowering children to use active coping strategies, and resilience building.

CONCLUSIONS

This diverse set of childhood, pain and parenting experts reached consensus on 187 items, yielding 12 key themes to consider when using everyday pain experiences to promote adaptive pain beliefs and behaviours in young children.

What do I need to know? Essential educational concepts for complex regional pain syndrome

Background

Methods

Results

Conclusion

Significance

The sensory and affective components of pain: are they differentially modifiable dimensions or inseparable aspects of a unitary experience? A systematic review

BACKGROUND

Pain is recognised to have both a sensory dimension (intensity) and an affective dimension (unpleasantness). Pain feels like a single unpleasant bodily experience, but investigations of human pain have long considered these two dimensions of pain to be separable and differentially modifiable. The evidence underpinning this separability and differential modifiability is seldom presented. We aimed to fill this gap by evaluating the current evidence base for whether or not the sensory and affective dimensions of pain can be selectively modulated using cognitive manipulations.

METHODS

A rigorous systematic search, based on a priori search terms and consultation with field experts, yielded 4270 articles. A detailed screening process was based on the following recommendations: (i) evaluation of effectiveness; (ii) examination of methodological rigour, including each study having an a priori intention to cognitively modulate one of the two dimensions of pain; and (iii) sound theoretical reasoning. These were used to ensure that included studies definitively answered the research question.

RESULTS

After in-depth critique of all 12 articles that met the inclusion criteria, we found that there is no compelling evidence that the sensory and affective dimensions of pain can be selectively and intentionally modulated using cognitive manipulations in humans.

CONCLUSIONS

We offer potential explanations for this discrepancy between assumptions and evidence and contend that this finding highlights several important questions for the field, from both the research and clinical perspectives.

Visually induced analgesia in a deep tissue experimental pain model: A randomised crossover experiment

BACKGROUND

Visualizing one's own painful body part appears to have an effect on reported pain intensity. Furthermore, it seems that manipulating the size of the viewed image can determine the direction and extent of this phenomenon. When visual distortion has been applied to clinical populations, the analgesic effects have been in opposition to those observed in some experimental pain models. To help resolve this problem, we explored the effect of visualisation and magnification of the visual image on reported pain using a delayed onset muscle soreness (DOMS) pain model.

METHODS

We induced DOMS in the quadriceps of 20 healthy volunteers. Forty-eight hours later, participants performed a series of painful contractions of the DOMS-affected muscle under four randomised conditions: (1) Viewing the injured thigh; (2) Viewing the contralateral thigh; (3) Viewing a neutral object; and (4) Viewing the injured thigh through magnifying glasses. For each condition, participants rated their pain intensity during a series of painful contractions.

RESULTS

We observed that direct visualisation of the injured thigh had no effect on pain intensity when compared to viewing the contralateral thigh or neutral object. However, magnification of the DOMS-affected leg during the performance of painful contractions caused participants to report more pain than when viewing the injured thigh normally.

CONCLUSIONS

These results further demonstrate that the effect of visualisation varies between different pain conditions. These results may have implications for the integration of visual feedback into clinical practice.

SIGNIFICANCE

We present delayed onset muscle soreness as a model for exploring visually induced analgesia. Our findings suggest that this phenomenon is expressed differently in exogenous and endogenous experimental pain models. Further exploration may offer a potential pathway for the integration of visual analgesia into the management of clinical pain.

Causal mechanisms in the clinical course and treatment of back pain

In recent years, there has been increasing interest in studying causal mechanisms in the development and treatment of back pain. The aim of this article is to provide an overview of our current understanding of causal mechanisms in the field. In the first section, we introduce key concepts and terminology. In the second section, we provide a brief synopsis of systematic reviews of mechanism studies relevant to the clinical course and treatment of back pain. In the third section, we reflect on the findings of our review to explain how understanding causal mechanisms can inform clinical practice and the implementation of best practice. In the final sections, we introduce contemporary methodological advances, highlight the key assumptions of these methods, and discuss future directions to advance the quality of mechanism-related studies in the back pain field.

Modulation of pain via expectation of its location

BACKGROUND

The spatial precision of expectancy effects on pain is unclear. We hypothesized that expecting nociceptive stimuli at particular skin sites would have an analgesic effect on nociceptive stimuli presented between them (middle zone).

METHODS

Laser stimuli (evoking pin-prick pain) were delivered to three discrete skin zones on the forearm, under two conditions. During 'Localization', participants' expectation of stimuli was spatially divided between two locations (expected stimuli in only the outer two skin zones): pain intensity and stimulus location were judged. During 'No-localization' (control condition), participants had no expectation concerning stimulus location; only pain intensity was rated. Additional experiments assessed the importance of the actual location on the forearm by: shifting all skin zones proximally towards the elbow (control for joint proximity, Experiment 2); adding a fourth zone distally (control for interaction between joint proximity and enhanced distal inhibition, Experiment 3).

RESULTS

All experiments demonstrated spatially specific pain modulation, but only Experiment 2 (near elbow) supported our hypothesis: middle zone pain intensity was significantly lower (p = 0.02) during Localization than No-localization. Experiment 1 (near wrist) found reduced pain intensity during Localization only for the distal zone (p = 0.04). Experiment 3 confirmed this effect: reduced pain during Localization occurred only for the most distal zone (p = 0.046).

CONCLUSION

Expecting a painful stimulus in non-adjacent skin sites has spatially specific effects on pain modulation, but this reflects an interaction between the expected location of stimulation and the actual location. This suggests a more complex connection between somatotopic maps and nociceptive modulation than previously thought; several distinct mechanisms likely contribute.

Elevated corticospinal excitability in patellar tendinopathy compared with other anterior knee pain or no pain

Anterior knee pain (AKP) is a frequent clinical presentation in jumping athletes and may be aggravated by sustained sitting, stair use, and loading of the quadriceps. Corticospinal activation of the quadriceps in athletes with AKP has not yet been investigated, but is important in guiding efficacious treatment. This cross-sectional study assessed corticospinal excitability (CSE) of the quadriceps in jumping athletes using transcranial magnetic stimulation (TMS). Groups consisted of Control (no knee pain); patellar tendinopathy (PT) [localized inferior pole pain on single-leg decline squat (SLDS)]; and other AKP (nonlocalized pain around the patella). SLDS (numerical score of pain 0-10), Victorian Institute of Sport Assessment Patellar tendon (VISA-P), maximal voluntary isometric contraction (MVIC), active motor threshold (AMT), CSE, and Mmax were tested. Twenty nine athletes participated; control n = 8, PT n = 11, AKP n = 10. There were no group differences in age (P = 0.23), body mass index (P = 0.16), MVIC (P = 0.38) or weekly activity (P = 0.22). PT had elevated CSE compared with controls and other AKP (P < 0.001), but no differences were detected between AKP and controls (P = 0.47). CSE appears to be greater in PT than controls and other AKP. An improved understanding of the corticospinal responses in different sources of knee pain may direct better treatment approaches.

The close proximity of threat: altered distance perception in the anticipation of pain

Pain is an experience that powerfully influences the way we interact with our environment. What is less clear is the influence that pain has on the way we perceive our environment. We investigated the effect that the anticipation of experimental pain (THREAT) and its relief (RELIEF) has on the visual perception of space. Eighteen (11F) healthy volunteers estimated the distance to alternating THREAT and RELIEF stimuli that were placed within reachable space. The results determined that the estimated distance to the THREAT stimulus was significantly underestimated in comparison to the RELIEF stimulus. We conclude that pain-evoking stimuli are perceived as closer to the body than otherwise identical pain-relieving stimuli, an important consideration when applied to our decisions and behaviors in relation to the experience of pain.

People with chronic facial pain perform worse than controls at a facial emotion recognition task, but it is not all about the emotion

Alexithymia, or a lack of emotional awareness, is prevalent in some chronic pain conditions and has been linked to poor recognition of others' emotions. Recognising others' emotions from their facial expression involves both emotional and motor processing, but the possible contribution of motor disruption has not been considered. It is possible that poor performance on emotional recognition tasks could reflect problems with emotional processing, motor processing or both. We hypothesised that people with chronic facial pain would be less accurate in recognising others' emotions from facial expressions, would be less accurate in a motor imagery task involving the face, and that performance on both tasks would be positively related. A convenience sample of 19 people (15 females) with chronic facial pain and 19 gender-matched controls participated. They undertook two tasks; in the first task, they identified the facial emotion presented in a photograph. In the second, they identified whether the person in the image had a facial feature pointed towards their left or right side, a well-recognised paradigm to induce implicit motor imagery. People with chronic facial pain performed worse than controls at both tasks (Facially Expressed Emotion Labelling (FEEL) task P < 0·001; left/right judgment task P < 0·001). Participants who were more accurate at one task were also more accurate at the other, regardless of group (P < 0·001, r(2)  = 0·523). Participants with chronic facial pain were worse than controls at both the FEEL emotion recognition task and the left/right facial expression task and performance covaried within participants. We propose that disrupted motor processing may underpin or at least contribute to the difficulty that facial pain patients have in emotion recognition and that further research that tests this proposal is warranted.

Using graded motor imagery for complex regional pain syndrome in clinical practice: failure to improve pain

BACKGROUND

There is good evidence from studies conducted in a single-centre research setting for the efficacy of graded motor imagery (GMI) treatment, a complex physiotherapy intervention, to reduce pain in long-standing complex regional pain syndrome (CRPS). However, whether GMI is effective in clinical practice is not established.

AIM

To establish whether GMI is effective in clinical practice.

METHODS

We undertook a prospective audit of GMI treatment at two UK centres with a special interest in the management of patients with CRPS. All patients received GMI, in conjunction with a range of other 'best practice' physical and psychological interventions.

RESULTS

The patients' average pain intensities did not improve with treatment [centre 1: n = 20, pre-post numeric rating scale (NRS) difference 0.6 [confidence interval (CI) -0.3 to 1.5]; centre 2: n = 12, pre-post NRS difference 0.2 (CI: -0.9 to 1.2)]. Patients at centre 1 reported significant functional improvement. Improved performance on left/right judgement replicated in both centres seen in the clinical trials.

CONCLUSIONS

The failure of our real-world implementation of GMI suggests that better understanding of both the GMI methodology and its interaction with other treatment methods is required to ensure that GMI research results can be translated into clinical practice. Our results highlight challenges with the translation of complex interventions for chronic pain conditions into clinical practice.

Disrupted working body schema of the trunk in people with back pain

BACKGROUND

To test whether working body schema of the trunk is disrupted in people with back pain using a motor imagery task in which one decides whether a pictured model has their trunk rotated to the left or to the right. The authors hypothesised that chronic back pain is associated with reduced accuracy of left/right trunk rotation judgements.

METHODS

21 Patients with back pain and 14 controls completed two tasks, each involving two trials of 40 images: a left/right hand judgement task, which was used as a control task, and the left/right trunk rotation judgement task. Two (task) × three (group: bilateral back pain, unilateral back pain and control) analyses of variance were undertaken on mean response time and accuracy.

RESULTS

Response time was similar across participants and tasks (NS). Accuracy was not. The patients with bilateral back pain made more mistakes on the left/right trunk rotation task than patients with unilateral back pain, who in turn made more mistakes on that task than the controls (body part × group interaction; p<0.001). The mean (95% CI) accuracy for left/right trunk rotation judgements was 53.4% (44.5% to 62.3%) for the patients with bilateral back pain, 67.2% (60.2% to 74.1%) for the patients with unilateral back pain and 87% (75% to 98%) for the control participants. This pattern was not observed on the left/right-hand judgement task, on which all three groups made correct judgements about 83% of the time (NS).

DISCUSSION

Chronic back pain is associated with disruption of the working body schema of the trunk. This might be an important contributor to motor control abnormalities seen in this population.

Disrupted cortical proprioceptive representation evokes symptoms of peculiarity, foreignness and swelling, but not pain

OBJECTIVES

It has been proposed that disruption of the internal proprioceptive representation, via incongruent sensory input, may underpin pathological pain states, but experimental evidence relies on conflicting visual input, which is not clinically relevant. We aimed to determine the symptomatic effect of incongruent proprioceptive input, imparted by vibration of the wrist tendons, which evokes the illusion of perpetual wrist flexion and disrupts cortical proprioceptive representation.

METHODS

Twenty-nine healthy and naive volunteers reported symptoms during five conditions: control, active and passive wrist flexion, extensor carpi radialis tendon vibration to evoke illusion of perpetual wrist flexion, and ulnar styloid (sham) vibration. No advice was given about possible illusions.

RESULTS

Twenty-one subjects reported the illusion of perpetual wrist flexion during tendon vibration. There was no effect of condition or of whether or not subjects reported an illusion on discomfort/pain (P>0.28). Peculiarity, swelling and foreignness were greater during tendon vibration than during the other conditions, and greater during tendon vibration in those who reported an illusion of wrist flexion than in those who did not (P<0.05 for all). Symptoms were reported by at least two subjects in each condition and four subjects reported systemic symptoms (e.g. nausea).

CONCLUSIONS

In healthy volunteers, incongruent proprioceptive input does not cause discomfort or pain but does evoke feelings of peculiarity, swelling and foreignness in the limb.

Experimental hand pain delays recognition of the contralateral hand—Evidence that acute and chronic pain have opposite effects on information processing?

Recognising the laterality of a pictured hand involves making an initial decision and confirming that choice by mentally moving one's own hand to match the picture. This depends on an intact body schema. Because patients with complex regional pain syndrome type 1 (CRPS1) take longer to recognise a hand's laterality when it corresponds to their affected hand, it has been proposed that nociceptive input disrupts the body schema. However, chronic pain is associated with physiological and psychosocial complexities that may also explain the results. In three studies, we investigated whether the effect is simply due to nociceptive input. Study one evaluated the temporal and perceptual characteristics of acute hand pain elicited by intramuscular injection of hypertonic saline into the thenar eminence. In studies two and three, subjects performed a hand laterality recognition task before, during, and after acute experimental hand pain, and experimental elbow pain, respectively. During hand pain and during elbow pain, when the laterality of the pictured hand corresponded to the painful side, there was no effect on response time (RT). That suggests that nociceptive input alone is not sufficient to disrupt the working body schema. Conversely to patients with CRPS1, when the laterality of the pictured hand corresponded to the non-painful hand, RT increased approximately 380 ms (95% confidence interval 190 ms-590 ms). The results highlight the differences between acute and chronic pain and may reflect a bias in information processing in acute pain toward the affected part.

Graded motor imagery is effective for long-standing complex regional pain syndrome: a randomised controlled trial

Complex regional pain syndrome type 1 (CRPS1) involves cortical abnormalities similar to those observed in phantom pain and after stroke. In those groups, treatment is aimed at activation of cortical networks that subserve the affected limb, for example mirror therapy. However, mirror therapy is not effective for chronic CRPS1, possibly because movement of the limb evokes intolerable pain. It was hypothesised that preceding mirror therapy with activation of cortical networks without limb movement would reduce pain and swelling in patients with chronic CRPS1. Thirteen chronic CRPS1 patients were randomly allocated to a motor imagery program (MIP) or to ongoing management. The MIP consisted of two weeks each of a hand laterality recognition task, imagined hand movements and mirror therapy. After 12 weeks, the control group was crossed-over to MIP. There was a main effect of treatment group (F(1, 11) = 57, P < 0.01) and an effect size of approximately 25 points on the Neuropathic pain scale. The number needed to treat for a 50% reduction in NPS score was approximately 2. The effect of treatment was replicated in the crossed-over control subjects. The results uphold the hypothesis that a MIP initially not involving limb movement is effective for CRPS1 and support the involvement of cortical abnormalities in the development of this disorder. Although the mechanisms of effect of the MIP are not clear, possible explanations are sequential activation of cortical pre-motor and motor networks, or sustained and focussed attention on the affected limb, or both.

A pain neuromatrix approach to patients with chronic pain

This paper presents an approach to rehabilitation of pain patients. The fundamental principles of the approach are (i) pain is an output of the brain that is produced whenever the brain concludes that body tissue is in danger and action is required, and (ii) pain is a multisystem output that is produced when an individual-specific cortical pain neuromatrix is activated. When pain becomes chronic, the efficacy of the pain neuromatrix is strengthened via nociceptive and non-nociceptive mechanisms, which means that less input, both nociceptive and non-nociceptive, is required to produce pain. The clinical approach focuses on decreasing all inputs that imply that body tissue is in danger and then on activating components of the pain neuromatrix without activating its output. Rehabilitation progresses to increase exposure to threatening input across sensory and non-sensory domains.