Pain Intensity In People Research Articles

Substance P concentration is associated with the inflammatory response and pain perception in patients with chronic pain in peripheral artery disease.

<b>Introduction:</b> Previous studies indicate a significant role of the inflammatory response in the etiopathogenesis of peripheral artery disease (PAD) and chronic pain (CP).<b>Aim:</b> The aim of the study was to determine the relationship between the concentration of SP and the level/concentration of inflammatory mediators (pro-inflammatory cytokines, positive and negative acute phase protein, anti-inflammatory cytokines) and pain intensity in people suffering from chronic pain (CP) in the course of PAD.<b>Material and methods:</b> We examined 187 patients of the Department of Vascular Surgery. As many as 92 patients with PAD and CP (study group) were compared to 95 patients with PAD without CP (control group). The relationship between SP and the level/concentration of fibrinogen, C-reactive protein (CRP), antithrombin III (AT), serum albumin, interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-α) and pain intensity (Numeric Rating Scale; NRS) was analyzed. Statistical analysis was performed using the R program, assuming the level of statistical significance of α = 0.05.<b>Results:</b> Patients with CP had significantly higher levels of fibrinogen (P < 0.001), CRP (P < 0.001), SP (P < 0.001), IL-10 (P < 0.001), and lower serum albumin levels (P < 0.023). Higher SP concentration was associated with higher levels of IL-10, CRP, and pain intensity. In both groups, SP concentration correlated negatively with the level of fibrinogen (P < 0.001) as well as with albumin in the control group (P < 0.001).<b>Conclusions:</b> Thus, there is a relationship between the concentration of SP and fibrinogen, along with CRP, IL-10, and the intensity of pain in people suffering from CP in the course of PAD, and the level of albumin in the group without CP.

COMPARISON OF THE EFFECT OF TWO REHABILITATION PROGRAMS ON SPINAL MOBILITY AND PAIN INTENSITY IN PATIENTS WITH SPINAL DISCOPATHY

Introduction. Approximately 80% of people experience back pain throughout their lives. A common problem of patients with low back pain is a significant limitation of mobility. Rehabilitation programs are usually recommended. Programs should include exercises that build flexibility, endurance, and strength. Kinesiotherapy is complemented by physiotherapy procedures, which are mainly aimed at analgesic and relaxing effects.
 The aim of the study was to compare the effect of two rehabilitation programs that differ in the type of kinesiotherapy on the mobility of the lumbar spine and the level of pain intensity in people with L5-S1 segment discopathy.
 Materials and methods. The study involved 30 patients undergoing 14 days of rehabilitation treatment. The criterion for dividing the subjects into groups was the method of kinesitherapy. The first group (Gr1) consisted of 15 patients who did gymnastics in the pool twice a day, and the second group (Gr2) consisted of 15 patients who attended therapeutic gymnastics classes in the gym twice a day. The exercises were aimed at improving the range of motion of the spine, strength and endurance of postural muscles. A visual analog scale was used to assess the intensity of pain. The distance between standard anthropometric points in the resting position and in the extreme position of movement was measured to assess the range of spinal movements.
 Results. After rehabilitation, the amplitude of movements of the lumbar spine increased in most patients. In Gr1, an increase in the range of forward spinal flexion by 9.2 cm (p = 0.001), rotation to the right by 0.63 cm (p = 0.03), and to the left by 1.33 cm (p = 0.007) was detected. In Gr2, the range of forward flexion increased by 12.6 cm (p = 0.005), left rotation by 0.94 cm (p = 0.035), and right flexion by 1.41 cm (p = 0.002). In the case of other movements, no statistically significant changes were found.
 In Gr1, the average pain intensity according to the VAS was 4.9 ± 2.3 points before the start of the physiotherapy program and 3.6 ± 1.7 points after its completion (p = 0.04). In Gr2, the VAS values were 5.1 ± 2.5 points and 3.9 ± 1.8 points, respectively (p = 0.03). The magnitude of changes in pain intensity was similar (-1.3 points and -1.2 points) for both programs.
 Conclusions. 1. The applied rehabilitation programs increased the mobility of the lumbar spine and reduced pain in patients with L5-S1 segment discopathy. 2. Both the hydrokinesitherapy program and the gym program were equally effective in increasing the range of motion of the spine and reducing the intensity of pain.

Efeitos mediadores do medo e ansiedade pré-operatórios na intensidade da dor pós-operatória

Abstract Objective To identify the mediating effects of preoperative fear and anxiety on postoperative pain intensity in people undergoing elective surgeries up to six months after surgery. Methods This is an observational and longitudinal study with quantitative analysis, carried out with 172 adult patients admitted to a hospital and undergoing elective surgeries. The instruments used were: form for characterizing sociodemographic, clinical and surgical variables; Hospital Anxiety and Depression Scale; Surgical Fear Questionnaire; and Numeric Rating Scale for pain assessment. The interviews were carried out during the preoperative period, 48 hours after surgery and monthly until six months after surgery. For the descriptive statistical analysis of the explanatory variables, the absolute and relative frequencies, mean, standard deviation, median and minimum and maximum values were used. The relationship between the variables studied was analyzed using measures of correlation and mediating effects (structural equation model, maximum likelihood method). Results During the postoperative period (6 months), the mean pain ranged from 4.86 to 1.19. The means for anxiety (7.62) and fear (25.2) related to surgery were calculated. The analysis of variables showed a positive correlation between both preoperative fear and anxiety with the highest pain levels assessed at different moments in the postoperative period. Furthermore, preoperative anxiety exerted a mediating effect on the relationship between fear related to surgery, manifested in the preoperative period, and postoperative pain in the first 48 hours after surgery. Conclusion Psychological variables, such as preoperative fear and anxiety, influenced postoperative pain intensity in people undergoing elective surgeries. Nursing interventions aimed at anxiety and fear may be useful for surgical patients.

Exploring Interactions Between Sex, Pain Characteristics, Disability, and Quality of Life in People With Chronic Spinal Pain: A Structural Equation Model

In people with nonspecific chronic spinal pain (nCSP), disability and quality of life are associated with clinical, cognitive, psychophysical, and demographic variables. However, evidence regarding the interactions between these variables is only limited to this population. Therefore, this study aims to explore path models explaining the multivariate contributions of such variables to disability and quality of life in people with nCSP. This secondary analysis uses baseline data from a randomized controlled trial including 120 participants with nCSP. Structural equation modeling was used to explore path models for the Pain Disability Index (PDI), the Short Form 36-item physical (SF-36 PC), and mental (SF-36 MC) component scores. All models included sex, pain catastrophizing, kinesiophobia, hypervigilance, and pain intensity. Additionally, the PDI and SF-36 PC models included pressure pain thresholds (PPTs) at the dominant pain site (ie, neck or low back). Significant associations were found between sex, pain cognitions, pain intensity, and PPTs. Only pain catastrophizing significantly directly influenced the PDI (P ≤ .001) and SF-36 MC (P = .014), while the direct effects on the SF-36 PC from kinesiophobia (P = .008) and pain intensity (P = .006) were also significant. However, only the combined effect of all pain cognitions on the SF-36 PC was mediated by pain intensity (P = .019). Our findings indicate that patients’ pain-related cognitions have an adverse effect on their physical health-related quality of life via a negative influence on their pain intensity in people with nCSP. PerspectiveThis secondary analysis details a network analysis confirming significant interactions between sex, pain cognitions, pain intensity, and PPTs in relation to disability and health-related quality of life in people with chronic spinal pain. Moreover, its findings establish the importance of pain cognitions and pain intensity for these outcomes. Trials registrationClinicaltrials.gov (NCT02098005).

The relationships between spinal amplitude of movement, pain and disability in low back pain: A systematic review and meta-analysis.

The role of spinal movement alterations in low back pain (LBP) remains unclear. This systematic review and meta-analyses examined the relationships between spinal amplitude of movement, disability and pain intensity in patients with LBP. We searched PubMed, CINAHL, Embase, Pedro and Web of Science for relevant articles until 14th March 2023. Risk of bias was assessed with the Quality in Prognostic Studies Tool. We analysed the relationships between amplitude of movement, disability and pain intensity with standard correlational meta-analyses and meta-analytic structural equation modelling (MASEM) in cross-sectional and longitudinal data. A total of 106 studies (9001 participants) were included. In cross-sectional data, larger amplitude of movement was associated with lower disability (pooled coefficient: -0.25, 95% confidence interval: [-0.29 to -0.21]; 69/5899 studies/participants) and pain intensity (-0.13, [-0.17 to -0.09]; 74/5806). An increase in amplitude of movement was associated with a decrease in disability (-0.23, [-0.31 to -0.15]; 33/2437) and pain intensity (-0.25, [-0.33 to -0.17]; 38/2172) in longitudinal data. MASEM revealed similar results and, in addition, showed that amplitude of movement had a very small influence on the pain intensity-disability relationship. These results showed a significant but small association between amplitude of movement and disability or pain intensity. Moreover, they demonstrated a direct association between an increase in amplitude of movement and a decrease in pain intensity or disability, supporting interventions aiming to reduce protective spinal movements in patients with LBP. The large meta-analyses performed in this work revealed an association between reductions in spinal amplitude of movement and increased levels of disability and pain intensity in people with LBP. Moreover, it highlighted that LBP recovery is associated with a reduction in protective motor behaviour (increased amplitude of movement), supporting the inclusion of spinal movement in the biopsychosocial understanding and management of LBP.

Cannabis-based medicines and medical cannabis for adults with cancer pain.

Cannabis-based medicines and medical cannabis for adults with cancer pain.

Treatments for kinesiophobia in people with chronic pain: A scoping review.

Kinesiophobia is associated with pain intensity in people suffering from chronic pain. The number of publications highlighting this relationship has increased significantly in recent years, emphasizing the importance of investigating and synthesizing research evidence on this topic. The purpose of this scoping review was to answer the following questions: (1) What types of interventions have been or are currently being studied in randomized controlled trials (RCTs) for the management of kinesiophobia in patients with chronic pain? (2) What chronic pain conditions are targeted by these interventions? (3) What assessment tools for kinesiophobia are used in these interventions? According to the studies reviewed, (1) physical exercise is the most commonly used approach for managing irrational fear of movement, (2) interventions for kinesiophobia have primarily focused on musculoskeletal pain conditions, particularly low back pain and neck pain, and (3) the Tampa Scale of Kinesiophobia is the most commonly used tool for measuring kinesiophobia. Future RCTs should consider multidisciplinary interventions that can help patients confront their irrational fear of movement while taking into account the patient’s personal biological, psychological, and social experiences with pain and kinesiophobia.

Effect of Graded Sensorimotor Retraining on Pain Intensity in Patients With Chronic Low Back Pain

The effects of altered neural processing, defined as altering neural networks responsible for perceptions of pain and function, on chronic pain remains unclear. To estimate the effect of a graded sensorimotor retraining intervention (RESOLVE) on pain intensity in people with chronic low back pain. This parallel, 2-group, randomized clinical trial recruited participants with chronic (>3 months) nonspecific low back pain from primary care and community settings. A total of 276 adults were randomized (in a 1:1 ratio) to the intervention or sham procedure and attention control groups delivered by clinicians at a medical research institute in Sydney, Australia. The first participant was randomized on December 10, 2015, and the last was randomized on July 25, 2019. Follow-up was completed on February 3, 2020. Participants randomized to the intervention group (n = 138) were asked to participate in 12 weekly clinical sessions and home training designed to educate them about and assist them with movement and physical activity while experiencing lower back pain. Participants randomized to the control group (n = 138) were asked to participate in 12 weekly clinical sessions and home training that required similar time as the intervention but did not focus on education, movement, and physical activity. The control group included sham laser and shortwave diathermy applied to the back and sham noninvasive brain stimulation. The primary outcome was pain intensity at 18 weeks, measured on an 11-point numerical rating scale (range, 0 [no pain] to 10 [worst pain imaginable]) for which the between-group minimum clinically important difference is 1.0 point. Among 276 randomized patients (mean [SD] age, 46 [14.3] years; 138 [50%] women), 261 (95%) completed follow-up at 18 weeks. The mean pain intensity was 5.6 at baseline and 3.1 at 18 weeks in the intervention group and 5.8 at baseline and 4.0 at 18 weeks in the control group, with an estimated between-group mean difference at 18 weeks of -1.0 point ([95% CI, -1.5 to -0.4]; P = .001), favoring the intervention group. In this randomized clinical trial conducted at a single center among patients with chronic low back pain, graded sensorimotor retraining, compared with a sham procedure and attention control, significantly improved pain intensity at 18 weeks. The improvements in pain intensity were small, and further research is needed to understand the generalizability of the findings. ANZCTR Identifier: ACTRN12615000610538.

Using cervical movement velocity to assist the prediction of pain and functional recovery for people with chronic mechanical neck pain

BackgroundImpaired cervical kinematics particularly the movement velocity had been consistently found in people with neck pain. The recovery and potential of cervical movement velocity in assisting the prediction of recovery in individuals with chronic neck pain remained unknown. This study investigated the application of cervical movement velocity to predict the outcomes of pain intensity and functional disability for a cohort of participants with chronic mechanical pain after completion of a 12-week intervention program. MethodsCervical movement velocity when performing neck motions in the anatomical planes, pain intensity and functional disability score were assessed before and after the physiotherapy program. Correlations between kinematic and clinical outcomes, and validity of applying the peak velocity values of the cervical spine measured at baseline for prediction of recovery of pain and function after the physiotherapy program were examined (n = 68). FindingsSignificant improvements were found in the peak values of cervical velocity in all movement planes, pain intensity and functional disability score at post-program reassessment (p < 0.001). Significant negative correlations between peak values of cervical movement velocity and pain intensity (for specific directions, r = −0.163 to −0.191), and functional disability were found (for all directions, r = −0.158 to −0.282). Area under the Receiver Operating Characteristics curve was >0.6 for cervical extension, flexion and right rotation velocity for predicting functional recovery post-program. InterpretationThese findings suggest that cervical velocity of selected planes measured at baseline may inform the prediction of recovery of functional disability but not pain intensity in people with chronic mechanical neck pain.

Effects of Virtual Reality-Based Rehabilitation Therapy on Pain Intensity in People with Low Back Pain: A Systematic Review and Meta-Analysis

Effects of Virtual Reality-Based Rehabilitation Therapy on Pain Intensity in People with Low Back Pain: A Systematic Review and Meta-Analysis

THE APPLICATION OF WARM WATER COMPRESSES WITH GINGER AND LEMONGRASS ON PAIN INTENSITY IN PATIENTS WITH GOUT ARTHRITIS

Background: Arthritis Gout or Gout is also a category of chronic non-communicable disease (NCD). Gout is a metabolic disease caused by excess levels of uric compounds in the body. A Pharmacological approach that can be used is the administration of NSAID drugs. The non-pharmacological approach can be in the form of education, setting a low-purine diet and pain management guidelines using warm compresses to reduce pain gout sufferers and improve or maintain function and quality of life. Objective: To determine the effect of warm water compresses application with pieces of ginger and lemongrass on pain intensity in patients with gout arthritis. Methods: This was a pre-experimental study with one group using pre and post-test approach. The sample was patients with gout arthritis who experienced pain in the joints as many as 25 respondents were selected using simple random sampling. The data analysis was using Wilcoxon Statistical Test. Result: This study was using respondents precentage for pre and post-test, the average respondent experienced moderate pain and after the intervention, the pain intesity decreased to relax and comfortable. Statistical test results showed p-value = 0.000&lt; =0.05, meaning that there was an effect of giving warm water compresses with pieces of ginger and lemongrass on the pain intensity of means that it had an impact on pain intensity in people with gout. Conclusion: This result showed that the application of warm water compresses with pieces of ginger and lemongrass could lowering the pain intensity in people with gout.

Pain Intensity and Pain Interference in People With Progressive Multiple Sclerosis Compared With People With Relapsing-Remitting Multiple Sclerosis

ObjectiveTo describe pain intensity and interference in people with progressive multiple sclerosis (MS), compare these with people with relapsing-remitting multiple sclerosis (RRMS), and identify common and unique factors associated with pain intensity in people with progressive MS and RRMS. DesignObservational, cross-sectional analysis using baseline data from a longitudinal survey on quality of life in participants with MS. SettingCommunity. ParticipantsA total of 573 adults with MS (N=573; progressive MS, n=142; RRMS, n=431). InterventionsNot applicable. Main Outcome MeasuresAverage pain intensity was measured by an 11-point numeric rating scale, and pain interference was measured by the Patient-Reported Outcomes Measurement Information System Pain Interference Short Form. ResultsParticipants with progressive MS reported moderate average pain intensity (3.22±2.50) and elevated pain interference (T score of 55.55±9.13). They did not differ significantly from those with RRMS in average pain intensity or pain interference. Common factors associated with higher average pain intensity were more severe disability, lower education level, unemployment, and current smoking. In those with progressive MS, older age was associated with lower average pain intensity. ConclusionsPain intensity and interference are similar across MS types. In addition to assessing and treating pain, it is important to screen for modifiable pain-related factors, such as smoking cessation, in this population.

Efficacy of the iDBT-Pain skills training intervention to reduce emotional dysregulation and pain intensity in people with chronic pain: protocol for a single-case experimental design with multiple baselines

IntroductionDifficulties in emotional regulation are key to the development and maintenance of chronic pain. Recent evidence shows internet-delivered dialectic behaviour therapy (iDBT) skills training can reduce emotional dysregulation and pain...

Effectiveness of Mindfulness-Based Interventions on Pain Intensity in Patients with Chronic Low Back Pain: A Systematic Review

Context: Chronic low back pain (CLBP) is the most prominent cause of disability worldwide. For the treatment of CLBP, Mindfulness-based Interventions (MBIs) such as mindfulness-based stress reduction (MBSR), mindfulness-based cognitive therapy (MBCT), mindfulness meditation (MM) are often used; however, their exact effect on pain intensity has not yet been determined for these people. Objectives: This study aimed to evaluate the effectiveness of MBIs on pain intensity in people with CLBP. Data Sources: In this systematic review, all of the randomized controlled trials available on PubMed, PsycInfo, Cochrane Library, Google Scholar, Scopus, and ProQuest databases from 2014 to 2020 were reviewed. This study is also the first review article in the field of chronic low back pain that reviews the databases of Google Scholar, Irandoc, and SID in Persian. Study Selection: Studies were included if they were: (1) RCT; (2) had patients with chronic low back pain; (3) made a comparison between MBIs and a passive comparator (usual care) or an active comparator (such as cognitive-behavioral therapy (CBT) or health education); (4) examined pain intensity. Results: In the initial search, we found 297 trials in total databases. After removing duplicates and applying all inclusion and exclusion criteria, 9 RCT (totaling 959 patients) with CLBP were included for this systematic review. Conclusions: MBIs are effective solutions for coping with CLBP, and their effects are maintained for a long time. No significant difference was found between the effectiveness of these treatments and CBT treatment on pain intensity of patients with CLBP.

The short-term effects of head-mounted virtual-reality on neuropathic pain intensity in people with spinal cord injury pain: a randomised cross-over pilot study.

Within-subject, randomised cross-over trial. To determine whether a commercially available 3D head-mounted (HMD) virtual reality (VR) device results in significant reductions in neuropathic pain compared to using a 2D screen device in people with spinal cord injury (SCI). Greenwich Hospital, Sydney, Australia. Sixteen men with established SCI and chronic neuropathic pain participated in a single-session randomised cross-over trial. We compared the effects of 3D HMD VR and a 2D screen application on SCI neuropathic pain intensity and levels of perceived presence. Participants reported significantly lower pain intensity after 3D HMD VR compared to 2D screen application (1.9 ± SD 1.8 versus 3.4 ± SD 1.6, mean 95% CI: 1.5, P < 0.0001). Participants reported significantly higher perceived levels of presence with the 3D HMD VR compared to 2D screen of (49.6 ± SD 8.9 versus 32.8 ± SD 11.1, mean 95% CI: 16.6, P < 0.0001). Increased perceived presence was associated with significantly lower pain intensity regardless of randomised sequencing of the two conditions (mean 95% CI: 0.06, P = 0.005). Effect size for pain reduction using 3D HMD VR was 0.80. We suggest that 3D HMD VR may provide neuropathic pain relief for people with SCI. Given the lack of cybersickness and ease of access, we propose that immersive VR could be a helpful adjunct to current pharmacotherapy. Further research is required to show that VR can be effective for more long-term reductions in SCI pain.

Pain Neuroscience Education Plus Usual Care Is More Effective than Usual Care Alone to Improve Self-Efficacy Beliefs in People with Chronic Musculoskeletal Pain: A Non-Randomized Controlled Trial

Self-efficacy beliefs are associated with less physical impairment and pain intensity in people with chronic pain. Interventions that build self-efficacy beliefs may foster behavioral changes among this population. A non-randomized trial has been carried out to evaluate the effectiveness of pain neuroscience education (PNE) plus usual care in modifying self-efficacy beliefs, pain intensity, pain interference and analgesics consumption in people with chronic musculoskeletal pain. Participants were allocated to an experimental (PNE plus usual care, n = 49) and a control (usual care alone, n = 51) group. The primary outcome was self-efficacy beliefs (Chronic Pain Self-Efficacy Scale), and the secondary outcomes were pain intensity, pain interference (Graded Chronic Pain Scale) and analgesics consumption. The participant’s pain knowledge (revised Neurophysiology of Pain Questionnaire) after PNE intervention was also assessed to analyze its influence on every outcome measure. All the outcome measures were assessed at the baseline and at four-week and four-month follow-ups. PNE plus usual care was more effective than usual care alone to increase self-efficacy beliefs and decrease pain intensity and pain interference at all follow-up points. No differences between groups were found in terms of analgesics consumption. Knowledge of pain neurophysiology did not modify the effects of PNE plus usual care in any of the outcome measures. These results should be taken with caution because of the non-randomized nature of this design, the limited follow-ups and the uncertainty of the presence of clinical changes in self-efficacy for participants. Larger, methodological sound trials are needed.

Spirituality in coping with pain in oncological patients: systematic review

ABSTRACT BACKGROUND AND OBJECTIVES: The relationship between spirituality and cancer coping is still a challenge for comprehensive health care. Therefore, it is necessary to analyze whether the level of spirituality directly interferes with clinical markers, such as pain intensity in people with cancer. The present study aims to investigate the relationship between spirituality and pain coping and the strategies used in adult cancer patients. CONTENTS: This is a systematic review, registered in the International Prospective Register of Systematic Reviews: CRD42018108835. The search was performed in Pubmed, Medline, LILACS, Scielo, and ScienceDirect databases until May 2019, available in all languages. The search strategy was defined for the PubMed database as a parameter: (neoplasms or cancer) AND (spirituality) AND (pain). Adults patients with cancer of both genders who faced pain were studied. Studies that did not address the pain associated with spirituality were excluded. Of the 588 studies found, 13 were eligible. Among these, nine studies showed that spirituality contributes to positive pain coping. Regarding the level of spirituality, higher spiritual well-being was associated with lower pain intensity in three studies. The spiritual strategies used were mindfulness, meditation, relaxation, prayer, support from religious leaders and members. CONCLUSION: Despite the few studies found, the findings broaden the knowledge about the positive relationship between spirituality and pain coping and underline the spiritual strategies for the management of this health condition in cancer patients.

Comparison of brain structure between pain-susceptible and asymptomatic individuals following experimental induction of low back pain

Background ContextPeripheral differences often do not adequately account for variation in reports of pain intensity in people with musculoskeletal pain. PurposeHere we sought to determine the extent to which structural differences in the brain (grey matter density) of pain free individuals might relate to subsequent pain (or lack thereof) after standardized peripheral muscle injury (ie, micro trauma from high intensity exercise). Study DesignThis was an observational laboratory-based study that was a secondary analysis from a larger trial. MethodsParticipants completed baseline testing (functional MRI and quantitative pain testing) followed by high intensity trunk exercise to induce delayed onset muscle soreness in the erector spinae. Forty-eight hours later, back pain intensity ratings were collected and all participants were re-imaged. Grey matter density was determined using voxel-based morphometry. The “asymptomatic” group (no reports of any pain within 48 hours after induction) to a ‘pain’ group (rating of pain at rest and movement pf>20 on a 101-point numeric rating scale). ResultsOur results revealed several large clusters where, compared to participants with pain, asymptomatic participants had significant greater grey matter density. These brain regions included left medial frontal gyrus, left middle occipital gyrus, left middle temporal gyrus, left inferior frontal gyrus, and right superior frontal gyrus. ConclusionsLower grey matter density in brain regions previously linked to discriminative, emotional, and cognitive aspects of cortical processing are associated with reporting musculoskeletal pain after a standardized peripheral muscle injury. Clinical SignificanceCortical gray matter density of people without any pain may influence response to a standardized high intensity exercise protocol. This finding adds further support to the relevance of central factors in explaining the tremendous individual variability in pain report following acute musculoskeletal injury.

Controlling for confounding via propensity score methods can result in biased estimation of the conditional AUC: A simulation study.

In the medical literature, there has been an increased interest in evaluating association between exposure and outcomes using nonrandomized observational studies. However, because assignments to exposure are not random in observational studies, comparisons of outcomes between exposed and nonexposed subjects must account for the effect of confounders. Propensity score methods have been widely used to control for confounding, when estimating exposure effect. Previous studies have shown that conditioning on the propensity score results in biased estimation of conditional odds ratio and hazard ratio. However, research is lacking on the performance of propensity score methods for covariate adjustment when estimating the area under the ROC curve (AUC). In this paper, AUC is proposed as measure of effect when outcomes are continuous. The AUC is interpreted as the probability that a randomly selected nonexposed subject has a better response than a randomly selected exposed subject. A series of simulations has been conducted to examine the performance of propensity score methods when association between exposure and outcomes is quantified by AUC; this includes determining the optimal choice of variables for the propensity score models. Additionally, the propensity score approach is compared with that of the conventional regression approach to adjust for covariates with the AUC. The choice of the best estimator depends on bias, relative bias, and root mean squared error. Finally, an example looking at the relationship of depression/anxiety and pain intensity in people with sickle cell disease is used to illustrate the estimation of the adjusted AUC using the proposed approaches.

A preliminary analysis of the association between perceived stigma and HIV-related pain in South Africans living with HIV.

BackgroundStigma related to the human immunodeficiency virus (HIV) remains common and has been associated with severity of HIV-related symptoms. Associations between HIV stigma and HIV-related pain, one of the most common symptoms in HIV, have however not been investigated. Data from low back pain populations suggest that stigma is associated with worse pain intensity and so we hypothesised that the same would be the case in HIV.AimThe goal of this study was to assess the association between HIV stigma and pain intensity in people living with HIV (PLWH) with chronic pain whilst controlling for depression, a well-established correlate of pain.SettingThe study took place at an HIV clinic in Johannesburg, South Africa.MethodsMediation analysis was used to assess the effect of depression on the relationship between stigma and pain intensity in a cross-sectional cohort of 50 PLWH and chronic pain (pain most days of the week for > 3 months). All participants were assessed using the HIV/AIDS Stigma Instrument – PLWA, an 11-point numerical pain rating scale and the Beck Depression Inventory II.ResultsIn all, 88% (44/50) of participants reported experiencing some form of HIV stigma (HIV stigma scale score ≥ 1). Worst pain intensity and depressive symptoms individually correlated with total stigma score (Spearman’s r = 0.33, p = 0.02 for both). The mediation analysis highlighted that mediation of the relationship by depression was equivocal (b = -0.002, bootstrapped confidence interval -0.02 to 0.00).ConclusionWhilst these preliminary data are marginal, they do suggest that associations between HIV stigma and HIV-related pain warrant further investigation. Future study should also include potential mechanisms, which may include mediation through depression.