The Role of Anxiety and Depression in Shaping the Sleep-Pain Connection in Patients with Nonspecific Chronic Spinal Pain and Comorbid Insomnia: A Cross-Sectional Analysis.

(1) Background: This exploratory study aims to explore the relationship between nonspecific chronic spinal pain (nCSP) and insomnia symptoms, by examining the interconnections, strengths, and directional dependence of the symptoms. In addition, we aim to identify the key symptoms of the nCSP-insomnia relationship and shed light on the bidirectional nature of this relationship. (2) Methods: This study is a secondary analysis of the baseline data (cross-sectional) from a randomized controlled trial, which examined the added value of Cognitive Behavioral Therapy for Insomnia (CBT-I) combined with cognition-targeted exercise therapy, conducted in collaboration with the Universiteit Gent and Vrije Universiteit Brussel (Belgium). One hundred and twenty-three nCSP patients with comorbid insomnia were recruited through the participating hospitals, advertisements, announcements in local newspapers, pharmacies, publications from support groups, and primary care. To explore the interconnections and directionality between symptoms and the strengths of the relationships, we estimated a regularized Gaussian graphical model and a directed acyclic graph. (3) Results: We found only one direct, but weak, link between sleep and pain, namely, between average pain and difficulties maintaining sleep. (4) Conclusions: Despite the lack of strong direct links between sleep and pain, pain and sleep seem to be indirectly linked via anxiety and depression symptoms, acting as presumable mediators in the network of nCSP and comorbid insomnia. Furthermore, feeling slowed down and fatigue emerged as terminal nodes, implying their role as consequences of the network.

Do Patients with Chronic Spinal Pain and Comorbid Insomnia Have More Features of Central Sensitization? A Case-Control Study.

BACKGROUND: Chronic spinal pain (CSP) is a major public health problem worldwide, frequently related to sleep problems. Central sensitization (CS) may worsen the clinical picture of CSP patients with insomnia. The aim of this study was to compare self-reported and objectively measured clinical outcomes between insomniac CSP patients with comorbid insomnia with and without symptoms of CS. METHODS: A case-control study on baseline self-reported sleep, functioning, and psychological distress through online questionnaires. Objective sleep and physical activity parameters and pressure pain thresholds (PPTs) were assessed through polysomnography, actigraphy, and digital algometry, respectively. Independent sample t-test and Mann-Whitney U tests were used to examine possible differences in the outcome measures between the groups. RESULTS: Data from 123 participants were included and revealed no statistically significant group for objective sleep and physical activity parameters. The CS group, however, presented with worse self-reported sleep (quality sleep, insomnia severity, and dysfunctional beliefs about sleep), increased mental and physical fatigue, and higher psychological distress (anxiety and depressive symptoms), and reported lower PPTs. CONCLUSIONS: symptoms of CS may influence perceived sleep and affect functional health and well-being perception but do not seem to affect objective sleep and physical activity.

Relationship, differences, and agreement between objective and subjective sleep measures in chronic spinal pain patients with comorbid insomnia: a cross-sectional study.

ABSTRACT: Sleep disturbances are one of the most frequent reported problems in people with nonspecific chronic spinal pain (nCSP) and presents an additional treatment challenge. Interventions targeting sleep problems are mainly based on subjective sleep complaints and do not take objective sleep into consideration. The aim of this cross-sectional study was to evaluate the relationship and conformity between self-reported and objectively measured sleep parameters (ie, questionnaire vs polysomnography and actigraphy). The baseline data of 123 people with nCSP and comorbid insomnia who are participating in a randomized controlled trial were analyzed. Pearson correlations were used to investigate the relationship between objective and subjective sleep parameters. Differences between objective and subjective sleep parameters were analyzed using t tests. Bland-Altman analyses were performed to quantify and visualize agreement between the different measurement methods. Except for the significant moderate correlation between perceived time in bed (TIB) and actigraphic TIB ( r = 0.667, P < 0.001), all other associations between subjective and objective measures were rather weak ( r < 0.400). Participants underestimated their total sleep time (TST) (mean difference [MD] = -52.37 [-67.94, -36.81], P < 0.001) and overestimated sleep onset latency (SOL) (MD = 13.76 [8.33, 19.20], P < 0.001) in general. The results of this study suggest a discrepancy (differences and lack of agreement) between subjective and objective sleep parameters in people with nCSP and comorbid insomnia. No or weak associations were found between self-reported sleep and objectively measured sleep. Findings suggest that people with nCSP and comorbid insomnia tend to underestimate TST and overestimate SOL. Future studies are necessary to confirm our results.

Predictors for physical activity and its change after active physical therapy in people with spinal pain and insomnia: Secondary analysis of a randomized controlled trial.

BACKGROUND: In healthy people and people with nonspecific chronic spinal pain (nCSP) and/or insomnia, participation in physical activity on a regular basis has several physical and psychological health benefits. However, people with chronic conditions often tend to reduce physical activity participation which can lead to deconditioning over time. Currently, there are no known predictors for an (in)active lifestyle (before and after physical therapy treatment) in people with chronic spinal pain and comorbid insomnia. OBJECTIVE: To examine predictors of pre-treatment moderate-to-vigorous physical activity (MVPA) and to examine determinants for a change in MVPA in response to 14-weeks of active physical therapy treatment in people with nonspecific chronic spinal pain (nCSP) and comorbid insomnia. METHODS: Baseline data and post-treatment data were analyzed for 66 participants. A linear multiple regression analysis was conducted to examine which factors predict MVPA at baseline. Linear mixed-effects modeling was used to identify determinants for change in MVPA in response to an active physical therapy treatment. RESULTS: Physical fatigue (b = -0.9; 95%CI: -1.59, -0.15), less limitations in functioning as a result of emotional problems (b = 0.1; 95%CI: 0.03, 0.10), mental fatigue (b = -1.0; 95%CI: -1.67, -0.43), lower general sleep quality (b= 0.7; 95%CI: 0.22, 1.17), and body mass index (b = -0.5; 95%CI: -0.93, -0.16) were significant predictors of baseline MVPA. The regression model explained 33.3% of the total variance in baseline MVPA. The change of MVPA in response to the treatment ranged from a decrease of 17.5 to an increase of 16.6 hours per week. No determinants for change in MVPA after treatment could be identified. CONCLUSION: People with nCSP and comorbid insomnia are more likely to engage in MVPA if they report, at baseline, lower sleep quality, fewer limitations in functioning resulting from emotional problems, lower body mass index, as well as less physical and mental fatigue.

Combining Cognitive Behavioral Therapy for Insomnia and Chronic Spinal Pain Within Physical Therapy: A Practical Guide for the Implementation of an Integrated Approach.

Most people who have nonspecific chronic spinal pain (nCSP) report comorbid insomnia. However, in current treatment strategies for nCSP, insomnia is usually not addressed. Considering the bidirectional interaction between pain and sleep and its underlying psychophysiological mechanisms, insomnia may increase the risk of developing adverse physical and psychological health outcomes and should thus no longer be left untreated. As suggested by previous pilot studies, adding cognitive behavioral therapy for insomnia to the contemporary evidence-based biopsychosocial physical therapy approach may also improve pain outcomes in nCSP. This manuscript aims to provide practical guidelines on hybrid physical therapy, including the combination of the following components: (1) pain neuroscience education (eg, to reconceptualize pain) and cognition-targeted exercise therapy (eg, graded exposure to functional daily life movements), and (2) cognitive behavioral therapy for insomnia (sleep psychoeducation, behavioral and cognitive therapy, correction of sleep hygiene, and relaxation therapy) can be deployed for the management of patients who have chronic spinal pain. Impact. Due to the major impact sleep disturbances have on pain and disability, insomnia as a comorbidity should no longer be ignored when treating patients with chronic spinal pain.

Reliability and discriminative validity of a screening tool for the assessment of neuromuscular control and movement control in patients with neck pain and healthy individuals.

BACKGROUND: To evaluate the reliability and discriminative validity of a proposed adapted tool for the assessment of movement control in patients with and without neck pain. METHOD: A cross-sectional study at a University hospital center involving 25 pain-free healthy controls and 25 patients suffering from neck pain. Participants were assessed by two raters for inter-rater reliability and 1 week afterwards by a same rater for intra-rater reliability. The assessment involved a test for the axioscapular (adapted scapular holding test; SHT) and craniocervical (adapted craniocervical flexion test; CCFT) region for which intra-class correlation coefficients (ICCs) were computed to define the reliability. Discriminative validity to distinguish patients from controls was assessed by cross-validated computation of sensitivity, specificity, positive and negative likelihood ratios, overall accuracy, and area under the curve. RESULTS: The proposed tool was able to reliably assess sensorimotor impairment in participants at the craniocervical region (ICCintra = [0.52-0.82]; ICCinter = [0.60-0.85]), left axioscapular region (ICCintra = [0.43-0.77]; ICCinter = 0.71-0.90), and right axioscapular region (ICCintra = [0.47-0.79]; ICCinter = [0.42-0.77]). Furthermore, the tool yielded a sensitivity of 0.86, a specificity of 0.57, and accuracy of 0.71 (based on cross-validation). CONCLUSION: The proposed tool is able to reliably evaluate patients based on their sensorimotor performance in the craniocervical and axioscapular region.Implications for rehabilitationNeck pain is related to sensorimotor impairment including neuromuscular differences and atypical sensormimotor control strategies.Clinicians should not avoid the challenging task of screening for sensorimotor impairment in patients reporting neck pain.The proposed tool supplemented with other tools might guide clinicians in the evaluation of sensorimotor impairment.

Influence of education level on the effectiveness of pain neuroscience education: A secondary analysis of a randomized controlled trial.

BACKGROUND: Current evidence supports the use of pain neuroscience education (PNE) in several chronic pain populations. However, the effects of PNE at group level are rather small and little is known about the influence of personal factors (e.g. level of education [LoE]). OBJECTIVE: To examine whether the effectiveness of PNE differs in chronic spinal pain (CSP) patients with high LOE (at least a Bachelor's degree) versus lower educated patients. METHOD: A total of 120 Belgian CSP patients were randomly assigned to the experimental (PNE) or control group (biomedical-focused neck/back school). Participants within each group were further subcategorized based on highest achieved LoE. ANOVA and Bonferroni post-hoc analyses were used to evaluate differences in effectiveness of the interventions between higher and lower educated participants. RESULTS: No differences between higher and lower educated participants were identified for pain-related disability. Significant interactions (P < .05) were found for kinesiophobia and several illness perceptions components. Bonferroni post-hoc analysis revealed a significant improvement in kinesiophobia (P < .001 and P < .002, medium effect sizes) and perceived negative consequences (P < .001 and P < .008, small effect sizes) in the PNE groups. Only the higher education PNE group showed a significant improvement in perceived illness cyclicity (P = .003, small effect size). Post-treatment kinesiophobia was significant lower in the higher educated PNE group compared to the higher educated control group (p < .001). CONCLUSION: Overall, the exploratory findings suggest no clinical meaningful differences in effectiveness of PNE between higher and lower educated people. PNE is effective in improving kinesiophobia and several aspects of illness perceptions regardless of LoE.

The Association between Sleep and Chronic Spinal Pain: A Systematic Review from the Last Decade.

Chronic spinal pain, including both neck and low back pain, is a common disabling disorder in which sleep problems are frequently reported as a comorbidity. The complex processes of both sleep and chronic pain seem to have overlapping mechanisms, which may explain their often established bidirectional relationship. This systematic review aims to investigate the assumed association between sleep and chronic spinal pain by providing an overview of the literature from the last decade. Eligible studies were obtained by searching four databases (PubMed, Embase, Web of Science, and PsycARTICLES). Articles were found relevant if they included a human adult population and investigated the possible association between sleep parameters and chronic spinal pain. Only studies published after January 2009 were included, as this review aimed to provide an update of a previous literature overview on this topic. The quality of the studies was assessed by risk of bias and level of evidence. A total of twenty-seven studies (6 cohort, 5 case-control, and 16 cross-sectional studies) were included in this systematic review. The methodological quality of these studies was low to moderate. The majority of studies reported weak to moderate evidence for an association between sleep parameters and chronic spinal pain, with more severe pain accompanied by more disturbed sleep. Addressing frequently reported sleep problems in chronic spinal pain patients therefore appears to be a necessary complement to pain management to achieve optimal treatment outcomes.

Associates of Insomnia in People with Chronic Spinal Pain: A Systematic Review and Meta-Analysis.

Insomnia is a major problem in the chronic spinal pain (CSP) population and has a negative impact on health and well-being. While insomnia is commonly reported, underlying mechanisms explaining the relation between sleep and pain are still not fully understood. Additionally, no reviews regarding the prevention of insomnia and/or associated factors in people with CSP are currently available. To gain a better understanding of the occurrence of insomnia and associated factors in this population, we conducted a systematic review of the literature exploring associates for insomnia in people with CSP in PubMed, Web of Science and Embase. Three independent reviewers extracted the data and performed the quality assessment. A meta-analysis was conducted for every potential associate presented in at least two studies. A total of 13 studies were found eligible, which together identified 25 different potential associates of insomnia in 24,817 people with CSP. Twelve studies had a cross-sectional design. Moderate-quality evidence showed a significantly higher rate for insomnia when one of the following factors was present: high pain intensity, anxiety and depression. Low-quality evidence showed increased odds for insomnia when one of the following factors was present: female sex, performing no professional activities and physical/musculoskeletal comorbidities. Higher healthcare use was also significantly related to the presence of insomnia. One study showed a strong association between high levels of pain catastrophizing and insomnia in people with chronic neck pain. Last, reduced odds for insomnia were found in physically active people with chronic low back pain compared to inactive people with chronic low back pain. This review provides an overview of the available literature regarding potential associates of insomnia in people with CSP. Several significant associates of insomnia were identified. These findings can be helpful to gain a better understanding of the characteristics and potential origin of insomnia in people witch CSP, to identify people with CSP who are (less) likely to have insomnia and to determine directions of future research in this area.

Culture-sensitive and standard pain neuroscience education improves pain, disability, and pain cognitions in first-generation Turkish migrants with chronic low back pain: a pilot randomized controlled trial.

Purpose: To compare the effectiveness of culture-sensitive and standard pain neuroscience education (PNE) on pain knowledge, pain intensity, disability, and pain cognitions in first-generation Turkish migrants with chronic low back pain (CLBP).Methods: Twenty-nine Turkish first-generation migrants with CLBP were randomly assigned to the culture-sensitive (n = 15) or standard PNE (n = 14) groups. Primary (pain knowledge, pain intensity, and disability) and secondary outcomes (pain beliefs, catastrophization, and fear of movement) were evaluated at baseline, immediately after the second session of PNE (week 1), and after 4 weeks.Results: There was a significant main effect of time in pain knowledge (p < .001), pain intensity (p = .03), disability (p = .002), organic and psychological pain beliefs (p = .002, p = .01), catastrophization (p = .002), and fear of movement (p = .02). However, no significant difference was found between groups in terms of all outcome measures (p > .05).Conclusions: Both PNE programs resulted in improvements in knowledge of pain, pain intensity, perceived disability, and pain cognitions. Nevertheless, the superiority of the culture-sensitive PNE approach could not be proved. Therefore, maybe migrants who are living in the host country for longer length of time do not need culturally adapted therapies due to cultural integration, while these adaptations might be essential for the recent migrants or the autochthonous population in Turkey. Further research is required to investigate the effects of culture-sensitive PNE alone or in combination with physiotherapy interventions in recent migrants or Turkish natives with CLBP.

Changes in Muscle Morphology in Female Chronic Neck Pain Patients Using Magnetic Resonance Imaging.

STUDY DESIGN: Population-based cross-sectional study. OBJECTIVE: The aim of this study was to gain a better understanding of changes in muscle morphology in patients with chronic idiopathic neck pain (CINP) and chronic whiplash-associated disorder (CWAD). SUMMARY OF BACKGROUND DATA: Worldwide, neck pain (NP) is a common health problem with high socioeconomic burden. A high percentage of these patients evolves toward chronic symptoms. Efficacy of treatments for these complaints remains variable. In current literature, changes in muscle morphology (muscle fat infiltration and cross-sectional area) have been reported in patients with NP, both CWAD and CINP. However, no strong conclusions could be made. METHODS: In this study, magnetic resonance imaging was used to obtain data on muscle morphology from 14 cervical flexor and extensor muscles in 117 female subjects with NP (CWAD = 37; CINP = 45) and healthy controls (HC = 35). RESULTS: The CWAD group had a significantly larger muscle fat infiltration in some extensor (semispinalis and splenius capitis, trapezius, obliquus capitis inferior) and flexor (sternocleidomastoid) muscles compared to the CINP and/or HC group. A significantly larger (muscle) cross-sectional area was found in some extensor (levator scapulae, semispinalis capitis, trapezius) and flexor (longus colli, longus capitis, sternocleidomastoid) muscles in the HC group compared to the CINP and/or CWAD group. No clear associations were found between group differences and factors as pain duration, kinesiophobia, and disability. CONCLUSION: The results in this study suggest changes in muscle morphology in both NP cohorts. These results show some similarities with earlier findings in this research domain. Further studies based on controlled longitudinal designs are needed to facilitate data compilation, to draw stronger conclusions, and to integrate them into the treatment of patients with chronic NP.Level of Evidence: 4.

Prevalence and risk factors of sleep disturbances in breast cancersurvivors: systematic review and meta-analyses.

BACKGROUND: Breast cancer remains the most frequently diagnosed malignancy among women worldwide, with rising incidence numbers. In Belgium, one out of eight women will be diagnosed with breast cancer. Fortunately, 80% of those breast cancer patients will still be alive 10 years after diagnosis due to improvements in screening and treatment strategies. However, an important portion of the breast cancer survivors (BCS) will face side effects, such as sleep disturbances, long after treatment ends. It has been demonstrated that untreated insomnia in BCS negatively impacts mood, physical symptoms, pain sensitivity, fatigue, and quality of life. Furthermore, insomnia is increasingly considered an independent risk factor for future depression in BCS. The importance of understanding sleep disturbances in cancer populations has been highlighted and recognized as warranting further research. Therefore, the purpose of this systematic review was to determine the prevalence and the risk factors for the development of sleep disturbances in BCS. METHODS: PubMed, Web of Science, and PEDro were systematically screened for studies encompassing data regarding the prevalence or risk factors of sleep disturbances in BCS. If possible, meta-analyses were performed. Subgroup analyses were undertaken based on the methodological quality, study design, type of sleep disturbance, and the use of a measurement tool with strong psychometric properties to investigate significant heterogeneity (I2 > 50%) across studies. RESULTS: A total of 27 studies were found eligible. The pooled estimate for sleep disturbances prevalence is 0.40 (95% confidence interval (CI) = [0.29-0.52], I2 = 100%, p < 0.00001) and ranged from 0.14 (95% CI = [0.04-0.24]) to 0.93 (95% CI = [0.91-0.95]). Subgroup analyses did not reduce the heterogeneity among studies. Meta-analyses were performed for seven risk factors. Significant differences for the odds of developing sleep disturbances were found for hot flashes (pooled OR (ORp) 2.25, 95% CI = [1.64-3.08], I2 = 0%, p = 0.90), race (ORp 2.31, 95% CI = [1.56-3.42], I2 = 0%, p = 0.47), and menopause (ORp 1.84, 95% CI = [1.11-3.06], I2 = 0%, p = 0.70). After withdrawing the studies that did not rely on the use of a measurement tool with strong psychometric properties, pain (ORp 2.31, 95% CI = [1.36-3.92], I2 = 27%, p = 0.25), depressive symptoms (ORp 3.20, 95% CI [2.32-4.42], I2 = 0%, p = 0.63), and fatigue (ORp 2.82, 95% CI = [1.98-4.02], I2 = 0%, p = 0.60) became significant as well, with a substantial decrease of heterogeneity. CONCLUSION: Prevalence for sleep disturbances ranged from 0.14 to 0.93 with the vast majority of the studies investigating insomnia and sleep-wake disturbances. High heterogeneity makes it difficult to draw firm conclusions. Pain, depressive symptoms, hot flashes, fatigue, non-Caucasian race, and menopausal status were significantly associated with increased odds for developing sleep disturbances.

The added value of cognitive behavioral therapy for insomnia to current best evidence physical therapy for chronic spinal pain: protocol of a randomized controlled clinical trial.

BACKGROUND: Insomnia is a highly prevalent and debilitating comorbidity that is often not addressed in therapy for chronic spinal pain (CSP). Given the close interaction between insomnia and CSP severity and related disability, targeting sleep problems during therapy could improve treatment outcomes in these patients. OBJECTIVE: Can cognitive behavioral therapy for insomnia (CBT-I) combined with the modern neuroscience approach (i.e. pain neuroscience education and cognition-targeted exercise therapy) reduce pain and improve sleep, physical activity and function in people with CSP and comorbid insomnia? METHODS: Participants: One-hundred-twenty participants with chronic spinal pain and comorbid insomnia Intervention: CBT-I combined with the modern neuroscience approach (experimental) compared to the modern neuroscience approach alone (control). Both interventions start with three sessions of pain neuroscience education, followed by six sessions of CBT-I and nine sessions of cognition-targeted exercise therapy in the experimental group, or 15 sessions of cognition-targeted exercise therapy in the control group. MEASUREMENTS: Primary outcome measure: self-reported pain severity (Brief Pain Inventory). SECONDARY OUTCOME MEASURES: pain sensitivity (pressure pain thresholds, and online questionnaires), sleep-related outcomes (home-based polysomnography and online questionnaires), physical activity (actigraphy), and function (online questionnaires). Online questionnaires will be completed at baseline, directly post-treatment, and at 3, 6 and 12 months post-treatment. Polysomnography, pressure pain thresholds and actigraphy will be carried out at baseline, post-treatment and at 12 months follow-up. DISCUSSION: Findings may provide (1) a novel therapeutic approach for people with CSP and comorbid insomnia to improve pain, sleep, physical activity and function, and (2) new treatment guidelines for professionals. TRIAL REGISTRATION: Clinicaltrials.gov NCT03482856 (https://clinicaltrials.gov/ct2/show/NCT03482856).

Development of culturally sensitive Pain Neuroscience Education for first-generation Turkish patients with chronic pain: A modified Delphi study.

BACKGROUND: Pain Neuroscience Education (PNE) has been recognized as an efficacious approach for chronic pain, but evidence for these findings have mainly been gathered in Caucasian patient populations. In recent years, it has been proposed that the treatment of pain and patient information materials should be culturally sensitive for different ethnic populations and cultures since cultural variations in pain beliefs and cognitions. OBJECTIVES: To culturally adapt PNE material for first-generation Turkish patients with chronic pain. DESIGN: A modified Delphi study with three consecutive rounds. METHOD: A total of 10 participants (8 experts and 2 first-generation Turkish patients with chronic pain) were recruited for this study. Three online questionnaire rounds were conducted to synthesize the perspectives and to reach agreement on the suggested PNE materials. RESULTS: Results on multiple-choice questions from the first round revealed that the compatibility of the visual information and the clarity of the message obtained lower scores. Examples, visual information (illustrations, pictures), and metaphors in the teaching materials and the home education leaflet were revised based on suggestions in Rounds 1 and 2. In Round 3, respondents reached an acceptable agreement level for the clinical usefulness of the PNE teaching materials and the home education material. CONCLUSIONS: Culturally sensitive PNE materials were produced for first-generation Turkish patients. Since the results of the present study only reveal perspectives of the experts, further validation of education materials may be required before they are recommended for Turkish patients in clinical practices.

Are Pain Beliefs, Cognitions, and Behaviors Influenced by Race, Ethnicity, and Culture in Patients with Chronic Musculoskeletal Pain: A Systematic Review.

BACKGROUND: Chronic pain has been considered as a biopsychosocial condition in which cognitive and emotional factors as well as biological factors significantly affect perception of pain. Race, ethnicity and culture have a crucial impact on illness beliefs, health care preferences, help-seeking behaviors, and acceptance of medical interventions. OBJECTIVES: The aim of the present study was to systematically review the current evidence regarding the racial, ethnic and cultural alterations and differences in pain beliefs, cognitions, and behaviors in patients with chronic musculoskeletal pain (MSKP). STUDY DESIGN: Systematic review. METHODS: This systematic review was conducted and reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-analyses guidelines (PRISMA). PubMed and Web of Science were searched. A first screening was conducted based on title and abstract of the articles. In the second screening, full-texts of the remaining articles were evaluated for the fulfilment of the inclusion criteria. The risk of bias was assessed with the modified Newcastle-Ottawa Scale. RESULTS: A total of 11 articles were included. The methodological quality of the included studies ranged from low to moderate. There is moderate evidence that African-Americans use more praying, hoping, and emotion-focused coping strategies than Caucasians. There is also preliminary evidence regarding the differences in some coping strategies such as distraction, catastrophizing, and problem-focused solving between African-Americans and Caucasians. Preliminary evidence exists regarding the differences in pain coping strategies between the US and Portugal; the US and Singapore; and among 4 French-speaking countries. It is found that Spanish patients with fibromyalgia (FM) have more negative illness perceptions than Dutch patients. There is preliminary evidence that Caucasians have higher self-efficacy than African-Americans. There is also preliminary evidence that New Zealanders have more internal health expectancies than patients from the US. Preliminary evidence is demonstrated that Caucasians with rheumatoid arthritis (RA) have more positive control beliefs than African-Americans. Lastly, there is preliminary evidence that patients from the US believe that they are more disabled, while Singaporeans interpret the pain more by a traditional biomedical perspective. LIMITATIONS: Only 11 articles were included. The small number of articles, wide range of assessment methods, and substantial risk of bias in the included studies led the investigator to draw conclusions cautiously. CONCLUSION: Preliminary to moderate evidence shows the differences in coping strategies, illness perceptions, self-efficacy, fear avoidance beliefs, locus of control, and pain attitudes in different populations. Further prospective and longitudinal studies using standard definitions for race, ethnicity or culture and valid questionnaires for each population are warranted to explore the racial, ethnic and cultural discrepancies in pain beliefs, cognitions, and behaviours. KEY WORDS: Chronic pain, musculoskeletal pain, pain beliefs, pain cognitions, pain behaviors, race, ethnicity, culture.

Central Pain Processing in Patients with Shoulder Pain: A Review of the Literature.

BACKGROUND: Shoulder pain is a common health problem in which changes in shoulder structure cannot always explain the patient's perceived pain. Central sensitization (CS) might play a role in a subgroup of these patients. METHODS: The literature was systematically reviewed to address the role of CS in patients with shoulder pain. Electronic databases PubMed and Web of Knowledge were searched for relevant studies. RESULTS: Eighteen full-text articles were included, methodological quality was scored, and information was extracted. Studies were clustered on those studying patients with musculoskeletal (MSK) shoulder pain and those studying patients with hemiplegic shoulder pain (HSP). In particular, quantitative sensory testing revealed hyperalgesia for pressure pain in the MSK group, whereas these results were inconsistent in patients with HSP. Conditioned pain modulation was reduced in patients with MSK shoulder pain, but functioned normally in the HSP group. CONCLUSION: This review has shown that great progress has been made toward a better understanding of neurophysiologic pain mechanisms in patients with shoulder pain. The presence of generalized mechanical hyperalgesia, allodynia, and impaired conditioned pain modulation in patients with MSK shoulder pain indicates the involvement of the central nervous system. Widespread somatosensory abnormalities observed in patients with HSP could suggest a central origin for their shoulder pain and predispose patients with HSP to develop CS, although results are inconsistent. Additional research is required adopting different assessment methods (especially dynamic methods) to establish the role of CS in patients with shoulder pain.