Evaluating Evidence for the Role of Sleep in Fibromyalgia: A Test of the Sleep and Pain Diathesis Model

Psychological Distress in Women with Fibromyalgia: The Roles of Body Appreciation, Self-Compassion, and Self-Criticism

BACKGROUND

While past research detected a direct link between symptoms of fibromyalgia (FM) and psychological distress, body appreciation was suggested as a viable mediator of this link. The aim of the present study was to further develop an explanatory model for the effect of FM on women's psychological distress and identify possible protective and risk factors. Specifically, it was hypothesized that self-compassion would moderate the indirect effect of body appreciation and self-criticism on psychological distress in women with FM.

METHOD

This study comprised a total of 293 women, aged 20-68 (M = 34.8, SD = 12.3), of whom 146 were women with FM and 147 were heathy controls. All the women completed questionnaires regarding demographic characteristics, depression (PHQ-9), anxiety (GAD-7), self-criticism (DEQ-SC), body appreciation (BAS2), and the self-compassion scale (SCS).

RESULTS

A moderated serial mediation model demonstrated lower body appreciation in participants with FM compared to controls. These lower levels of body appreciation, together with lower levels of self-compassion, were associated with greater self-criticism and, consequently, higher levels of psychological distress.

CONCLUSIONS

The results emphasize the role of self-compassion as a protective mechanism against psychological distress among women with FM. Future studies should further investigate the effect of self-compassion-focused interventions on patients with FM.

The role of pain intensity and depressive symptoms in the relationship between sleep quality and postural control among middle-aged and older adults with Fibromyalgia

OBJECTIVE

Fibromyalgia (FM) is a chronic pain condition often accompanied by sleep problems and depression that are each associated with reduced physical ability including postural control. Research supports a sequential association between pain intensity and depression in FM, and poor sleep quality may play a key role in this relationship. This study aimed to verify a serial pattern of associations among sleep quality, pain intensity, and depressive symptoms and quantify these effects on objective postural control.

DESIGN

Community-residing adults diagnosed with FM (n = 155; Mage = 61.08, SD = 7.70; 93% female; 79% White) were included in this cross-sectional study.

MAIN OUTCOMES

Participants self-rated sleep quality (restorative sleep, sleep waking, and sleep latency), pain intensity, and depressive symptoms, and the Fullerton Advanced Balance (FAB) scale and 8-Foot Up and Go Test (8FUPGT) measured objective postural control.

RESULTS

Findings indicated that the serial association between pain intensity and depressive symptoms fully mediated the relationship between sleep quality and both FAB (95% CI [-.125, -.013]), and 8FUPGT (95% CI [.002, .033]) performance.

CONCLUSION

Findings highlight the serial association of pain intensity and depressive symptoms with objective postural control performance and the potential for sleep and depression interventions that may maximize functional outcomes in FM.

Mapping the associations of daily pain, sleep, and psychological distress in a U.S. sample

Chronic pain, sleep problems, and psychological distress (PD) can be disabling conditions and previous research has shown that they are associated. The nuances of the comorbid nature of these conditions may be important to understand for those who treat these conditions. This study examined the bidirectional associations of these health factors concurrently and over time in a sample of U.S. adults (N = 1,008, Mage = 57.68) from the Midlife in the United States (MIDUS) study. Participants reported on their daily pain, sleep quantity, and psychological distress over eight days. A modified Random Intercept Cross-lagged Panel Model was used to analyze the relations, starting with the whole sample and then a comparison of those with and without chronic pain. Results indicated that nightly variation in sleep quantity predicted next day psychological distress for both groups. Sleep quantity also predicted next-day pain, but only for individuals with chronic pain. Associations between pain and psychological distress were found both at the daily level and individual (between-person) level. This between-person association was stronger for those with chronic pain. The lagged associations between sleep, and both pain and psychological distress for the chronic pain group indicate that, increased quantity of sleep predicts decreased next-day pain and psychological distress. Providers could consider this unidirectional lagged relationship when prioritizing treatment for patients with these comorbid conditions. Future research may examine whether responsive, just-in-time treatments might intervene after participants wake from a poor night's sleep to counteract the negative effects of reduced sleep on PD and pain.

Catastrophizing and acceptance are mediators between insomnia and pain intensity-an SQRP study of more than 6,400 patients with non-malignant chronic pain conditions

Background

Sleep problems (insomnia) and chronic pain are associated. Chronic pain and insomnia/insufficient sleep quality share similar symptoms and features. Although they have a bidirectional relationship, more research is needed to understand how they interact via mediators and how moderators influence this relationship.

Aims

In this large clinical registry-based cohort study (N = 6,497), we investigate important mediators between insomnia and pain intensity in a cross-sectional sample of chronic pain patients using advanced path analysis. In addition, we investigate whether some background variables were moderators of the identified important paths or not and the correlation patterns between insomnia and pain intensity in relation to the mediators.

Methods

This study includes a cohort of adult patients with chronic non-cancer pain from the Swedish Quality Registry for Pain Rehabilitation (SQRP) with data on patient-reported outcome measures (PROMs) (2008-2016). The PROMs cover the background, pain aspects, psychological distress, pain-related cognitions, activity/participation, and health-related quality of life variables of the patients. Partial least squares structural equation modeling was used to explore the direct and indirect (via mediators) relationships between insomnia and pain intensity at baseline.

Results

In this cohort study, insomnia was prevalent at 62.3%, and both direct and indirect mediating paths were present for the insomnia-pain intensity relationship. All of the mediating effects combined were weaker than the direct effect between insomnia and pain intensity. The mediating effects via catastrophizing and acceptance showed the strongest and equal mediating paths, and mediating effects via fear avoidance were the second strongest. Insomnia showed stronger direct significant correlations with psychological distress, catastrophizing, and acceptance compared with those of pain intensity. Sex, age, education level, spatial extent of pain, or body mass index did not moderate the mediating paths.

Discussion and conclusion

This study confirms the existence of significant direct and mediating paths between reported insomnia and pain intensity. Future studies should focus on illuminating how sleep interventions influence pain intensity and other important key factors that contribute to the distress of chronic pain patients.

Fibromyalgia status and depressive symptoms are linked to body mass index and physical performance in mid to late life

Fibromyalgia (FM) is a chronic pain condition that is frequently accompanied by comorbid conditions, including depression. Depression is associated with reduced physical functioning and health, disproportionately affecting middle-aged and older adults with FM. This study examined associations between FM status and depressive symptoms with body mass index (BMI) and several physical performance indicators among middle-aged and older adults. Participants included 239 community-dwelling middle-aged and older adults with or without FM. Depressive symptoms were measured using the Beck Depression Inventory-II (BDI-II), BMI was objectively assessed, and physical performance was measured using the Fullerton Advanced Balance scale, 6-minute walk test, 30-second chair stand, and 8-foot up and go test. A path model using structural equation modeling yielded good fit and revealed that, compared to pain-free adult controls, participants with FM reported more depressive symptoms, which were in turn associated with reduced physical performance across all indicators except BMI, after adjusting for age and symptom severity. Findings suggest that individuals with FM demonstrate disproportionately higher depressive symptoms compared to non-FM controls, which may diminish physical performance after accounting for ageand symptom severity. This study supports FM status and depressive symptoms as important considerations when evaluating the health and disability risk of aging adults.

Preoperative Depression and Anxiety Impact on Inpatient Surgery Outcomes: A Prospective Cohort Study

Objectives

To determine the association of preoperative mood symptoms and postoperative adverse outcomes; to explore sex-specific differences.

Background

Depression and anxiety can increase postoperative mortality. Psychological stress is associated with a chronic inflammatory response unfavorable to postsurgical healing.

Methods

Prospective cohort study. Patients were recruited from surgical preadmission clinics at a university hospital. Preoperative depression and anxiety were measured via the Beck Depression and Beck Anxiety Inventories (BDI-II and BAI). Our primary outcome was a composite of postoperative complications, extended length of stay (ELOS) and early readmission. Associated variables included demographics, preoperative pain, pain tolerance/catastrophizing, coping mechanisms, postoperative pain, and opioid use. We adjusted for age, comorbidities, and surgical specialty.

Results

Of 1061 recruited patients (ten surgical specialties, 2015-2020), 455 males and 486 females had preoperative and postoperative data available. Mean age was 62.9 (range 20.2-96.2). At baseline, 9.3% of patients had moderate or severe depression; 7.4% had moderate or severe anxiety. Females were more likely to be moderately or severely depressed (11% vs 7%, P = 0.036) and moderately or severely anxious (9% vs 6%, P = 0.034). Females had significantly fewer reported comorbidities and lower American Society of Anesthesiologists category (P < 0.001). Increasing BDI-II and BAI scores significantly increased likelihood of postoperative complications, ELOS, and/or hospital readmission in females (adjusted odds ratio [aOR] = 2.57 for BDI-II 1-19 vs 0, P = 0.041; aOR = 4.48 for BDI-II > 19 vs 0, P = 0.008; aOR = 1.54 for BAI ≤ 6 vs >6, P = 0.038) but not in males. Mood symptoms did not influence postoperative pain or opioid use.

Conclusion

Preoperative depression and anxiety negatively impact surgical outcomes in female patients undergoing major surgery.

Impact of sleep disturbances and autonomic dysfunction on the quality of life of patients with fibromyalgia

OBJECTIVES

Fibromyalgia, a painful musculoskeletal disorder is associated with sleep disturbances as well as autonomic dysfunction. Pathophysiology of fibromyalgia is yet not clear and neuroanatomical proximity of sleep and autonomic centre prompts probable involvement of the two impacting the quality of life of fibromyalgia patients. Present study was done with the objective to explore the extent of sleep disturbances and/or autonomic dysfunction in fibromyalgia and asses their impact on quality of life of fibromyalgia patients.

METHOD AND MATERIALS

Thirty consecutive fibromyalgia patients (diagnosed by ACR 2010) from out-patient department and 30 age-gender matched controls were enrolled after the ethical clearance. All participants were evaluated for: (1) sleep using Pittsburgh sleep quality index and medical outcomes study sleep scale-12 Revised, (2) Quality of life by 36 item short-form health survey-36v2TM and revised fibromyalgia impact questionnaire (only patients). Autonomic functions of patients were evaluated by standard cardiovascular autonomic function tests by Ewing's battery and heart rate variability (5-min) measurement.

RESULTS

Fibromyalgia patients had increased sleep disturbances compared to controls (39.46 ± 11, 59.61 ± 2.31; p=0.0001) and very poor sleep quality (13.63 ± 4.15, 3.03 ± 1.56; p=0.0001) as well as quality of life (p=0.0001) which further deteriorated with increasing severity of fibromyalgia. Twelve patients had autonomic dysfunction but it was neither associated with sleep disturbances nor with quality of life.

CONCLUSIONS

Mild to moderate grade fibromyalgia patients have significant sleep disturbance, poor sleep quality which remarkably impacts their quality of life. Autonomic dysfunction is not an early feature of disease. The study suggests that full spectrum of sleep disturbances and sleep quality should be explored in fibromyalgia syndrome (FMS) patients.

Investigating the roles of age, sex, depression, and anxiety for valence and arousal ratings of words: a population-based study

BACKGROUND

The perception of the affective quality of stimuli with regard to valence and arousal has mostly been studied in laboratory experiments. Population-based research may complement such studies by accessing larger, older, better balanced, and more heterogeneous samples. Several characteristics, among them age, sex, depression, or anxiety, were found to be associated with affective quality perception. Here, we intended to transfer valence and arousal rating methods from experimental to population-based research. Our aim was to assess the feasibility of obtaining and determining the structure of valence and arousal ratings in the setting of the large observational BiDirect Study. Moreover, we explored the roles of age, sex, depression, and anxiety for valence and arousal ratings of words.

METHODS

704 participants provided valence and arousal ratings for 12 written nouns pre-categorized as unpleasant, neutral, or pleasant. Predictors of valence and arousal ratings (i.e. age, sex, depression, and anxiety) were analyzed for six outcomes that emerge by combining two affective dimensions with three words categories. Data were modeled with multiple linear regression. Relative predictor importance was quantified by model-explained variance decomposition.

RESULTS

Overall, average population-based ratings replicated those found in laboratory settings. The model did not reach statistical significance in the valence dimension. In the arousal dimension, the model explained 5.4% (unpleasant), 4.6% (neutral), and 3.5% (pleasant) of the variance. (Trend) effects of sex on arousal ratings were found in all word categories (unpleasant: increased arousal in women; neutral, pleasant: decreased arousal in women). Effects of age and anxiety (increased arousal) were restricted to the neutral words.

CONCLUSIONS

We report results of valence and arousal ratings of words in the setting of a large, observational, population-based study. Method transfer yielded acceptable data quality. The analyses demonstrated small effects of the selected predictors in the arousal dimension.

Sleep and Pain: A Systematic Review of Studies of Mediation

Supplemental Digital Content is available in the text.

Objectives:

A relationship between sleep and pain is well established. A better understanding of the mechanisms that link sleep and pain intensity is urgently needed to optimize pain management interventions. The objective of this systematic review was to identify, synthesize, and critically appraise studies that have investigated putative mediators on the path between sleep and pain intensity.

Methods:

A systematic search of 5 electronic bibliographic databases (EMBASE, MEDLINE, CINAHL, PsycINFO, and the Cochrane Central Register of Controlled Trials) was conducted. Eligible studies had to apply a formal test of mediation to variables on the path between a sleep variable and pain intensity or vice versa. All searches, data extraction and quality assessment were conducted by at least 2 independent reviewers.

Results:

The search yielded 2839 unique articles, 9 of which were eligible. Of 13 mediation analyses, 11 investigated pathways from a sleep variable to pain intensity. Putative mediators included affect/mood, depression and/or anxiety, attention to pain, pain helplessness, stress, fatigue, and physical activity. Two analyses investigated pathways from pain intensity to a sleep variable, examining the potentially mediating role of depressive symptoms and mood. Although evidence supported a mediating role for psychological and physiological aspects of emotional experiences and attentional processes, methodological limitations were common, including use of cross-sectional data and minimal adjustment for potential confounders.

Discussion:

A growing body of research is applying mediation analysis to elucidate mechanistic pathways between sleep and pain intensity. Currently sparse evidence would be illuminated by more intensively collected longitudinal data and improvements in analysis.

Effect of pain on mood affective disorders in adults with cerebral palsy

AIM

To determine if pain is associated with 12-month incidence of mood affective disorders (MAD) in adults with cerebral palsy (CP).

METHOD

Data from Optum Clinformatics^® Data Mart (2013-2016) were used for this retrospective cohort study. Diagnostic codes were used to identify adults (≥18y) with CP, incident cases of MAD, and covariates (other neurodevelopmental conditions, sleep disorders, arthritis). Pain (any type, location) was identified between 1st October 2014 and 30th September 2015. The pain group was divided into new or consistent pain if they had a history of pain (i.e. consistent) in the 12 months before their first pain claim date. Crude incidence rates of MAD (expressed per 100 person-years) were estimated. Cox regression was used to estimate hazard ratio (95% confidence interval [CI]) of MAD after adjusting for covariates.

RESULTS

Adults that had new pain (n=859; incidence rate=15.5) or consistent pain (n=1303; incidence rate=17.9) had greater crude incidence rate of MAD compared to adults without pain (n=3726; incidence rate=5.9). The elevated rate of MAD remained after adjusting for covariates, for new pain (hazard ratio=2.4; 95% CI=1.9-3.0) and consistent pain (hazard ratio=2.1; 95% CI=1.7-2.7).

INTERPRETATION

Pain is associated with greater incidence of MAD in adults with CP. This association remained after accounting for potential confounding factors.

WHAT THIS PAPER ADDS

What this paper adds Pain was associated with higher 12-month incidence of mood affective disorders (MAD). The 12-month MAD incidence was similar between new and consistent pain groups. The MAD incidence remained higher adjusting for neurodevelopmental comorbidities, sleep disorders, and arthritis.

Emotional affection on a sustained attention task: The importance the aging process and depression

Chronic pain is a complex experience that has now become a major public health issue. This has prompted many researchers to study attention, understanding it to be a crucial factor that allows altering the experience of pain, while attributing considerable importance to sustained attention. Accordingly, the main studies in this field stress the importance of emotion regulation processes and emotions on the perception of painful stimuli and attentional processes themselves. Nevertheless, only a handful of studies have been found that directly study the relationship between these variables. Within this context, this article sets out to analyse emotional regulation processes, emotional variables (depression and anxiety), the experience of pain, and age on the ability to maintain the vigilance response in a sample of patients with chronic pain. This involved selecting a sample of 49 patients with rheumatoid arthritis and examining their performance in an ad-hoc sustained attention test. With a view to complying with the study's main purpose, the participants were also assessed through the use of the following self-report measures: the Beck Depression Inventory (BDI-I); the Hospital Anxiety and Depression Scale (HADS); the McGill Pain Questionnaire, and the Difficulties in Emotion Regulation Scale (DERS). Linear regression analyses revealed a significant impact of the aging process on the performance times in the attention task. Likewise, age and depression recorded a significant correlation with the mistakes made during the task. These results suggest that higher depression levels and an older age might be related to a worse adaptation to pain management techniques based on attention processes, such as mindfulness.

Sleep and pain management: a review

There is a complex interplay between sleep disturbance and patients in pain. There is an increasing appreciation of the direct effects of analgesic drugs and sleep quality. This review provides an overview of the effects of different analgesic drugs and their effects on phases of sleep. The effects of different pain conditions and their direct effects on sleep physiology are also discussed. A structured search of the scientific literature using MEDLINE and PubMed databases. Original human and animal studies were included. A multi-search term strategy was employed. An appreciation of the physiological effects of these drugs will allow a more considered prescription of them to better manage sleep disturbance.

Factors Associated With Sleep Quality in Patients With Chronic Widespread Pain Attending Multidisciplinary Treatment

PURPOSE

(1) To investigate the prevalence of poor sleep quality and (2) to explore the associations between clinical, cognitive, and emotional factors and quality of sleep in patients with chronic widespread pain (CWP) receiving multidisciplinary treatment.

METHOD

Baseline data were used from 163 patients with CWP referred for multidisciplinary treatment. Linear regression models were used to assess the relationship of clinical (pain, fatigue, pain interference, and disability), emotional (anxiety, depression, and psychological distress), and cognitive factors (catastrophizing, acceptance, self-efficacy, kinesiophobia and illness beliefs) with sleep quality, as measured using the Pittsburgh Sleep Quality Index.

RESULTS

Poor sleep quality was found in 92% of the patients. The multivariable model showed that a higher level of fatigue (b = 1.77, standard error [SE] = 0.62, β = 0.21, t = 2.87, P < 0.01), psychological distress (b = 0.02, SE = 0.01, β = 0.27, t = 3.50, P < 0.01), and more concerns about the illness (b = 0.46, SE = 0.18, β = 0.20, t = 2.57, P = 0.01) were independently associated with poorer quality of sleep. The overall linear regression model explains 27.9% of sleep quality.

CONCLUSIONS

The high prevalence of poor sleep quality in patients with CWP referred for multidisciplinary treatment emphasizes the need to target sleep during treatment. Further research is needed to disentangle the cause-effect relationship between fatigue, psychological distress, and concerns about the illness and poor sleep (note: this abstract has been published before [Ann Rheum Dis. 2018;77:A1788]).

Clinical factors associated with mood affective disorders among adults with cerebral palsy

Objective

To determine individual and aggregated associations of cerebral palsy (CP)-related symptoms and the effect of comorbid neurodevelopmental conditions on mood (affective) disorders among adults with CP.

Methods

Cross-sectional data from 2016 were extracted from a random 20% sample of the Medicare fee-for-service database. International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes were used to identify 18- to -64-year-old beneficiaries with CP, as well as mood (affective) disorders, pain, sleep disorders, fatigue, and comorbid neurodevelopmental conditions (intellectual disabilities [ID], autism spectrum disorders [ASD], and epilepsy).

Results

Four thousand eight hundred twenty-three of the 17,212 adults with CP had mood (affective) disorders (28.0%). After adjusting for age, sex, and race, pain (odds ratio [OR] = 2.15; 99.5% confidence interval [CI] = 1.94-2.39), sleep disorders (OR = 2.43; 99.5% CI = 2.13-2.77), fatigue (OR = 1.38; 99.5% CI = 1.18-1.60), ID (OR = 1.47; 99.5% CI = 1.31-1.63), ASD (OR = 1.44; 99.5% CI = 1.16-1.80), and epilepsy (OR = 0.81; 99.5% CI = 0.73-0.91) were each associated with mood (affective) disorders. When pain, sleep disorders, and fatigue were presented as a count variable, the adjusted odds of mood (affective) disorders increased with the number of factors: 1 factor (OR = 1.99; 99.5% CI = 1.79-2.22), 2 factors (OR = 4.18; 99.5% CI = 3.58-4.89), and all 3 factors (OR = 7.38; 99.5% CI = 5.17-10.53).

Conclusions

Among young and middle-aged adults with CP, mood (affective) disorders were associated with pain, sleep disorders, and fatigue, and increasing co-occurrence of these factors further increased the likelihood of mood (affective) disorders. Further, comorbid neurodevelopmental conditions were also associated with mood (affective) disorders among adults with CP. Study findings could be used to improve screening strategies for mood (affective) disorders among adults with CP in the clinical setting.

The Interrelationship between Sleep and Chronic Pain in Adolescents

Over half of youth with chronic pain report sleep deficiency including difficulties falling asleep, maintaining sleep, feeling unrested, and experiencing short sleep duration. Sleep deficiency has been shown to play a causal role in the development or worsening of chronic pain, and is associated with a variety of negative consequences for youth with chronic pain. The purpose of this review is to provide a summary of the literature on the interrelationship of sleep and chronic pain in adolescents. We review the impact and prevalence of sleep disturbances, conceptual models of the interrelationship of sleep and pain, biobehavioral mechanisms and risk factors, sleep assessment, and treatment of sleep deficiency and chronic pain in adolescents. Our recommendations for future research include understanding biobehavioral mechanisms that underlie the link between chronic pain and sleep deficiency to help guide development and testing of treatments for co-occurring pain and sleep disturbance in adolescents.

Sleep quality among industrial workers: related factors and impact

Purpose

The purpose of this paper is to explore the prevalence and determinants of poor sleep quality among industrial workers in Thailand. Additionally, the authors assess the risk of work-related injuries associated with poor sleep quality.

Design/methodology/approach

A descriptive correlational research was implemented. A total of 472 workers from the northern region of Thailand contributed to this study. Sleep quality was assessed by the Thai version of the Pittsburgh Sleep Quality Index (Thai-PSQI). The score of more than five indicated poor sleep quality. Participants completed self-administered demographic, work characteristics and work-related injury questionnaires. Data were analyzed by applying descriptive and logistic regression statistical techniques.

Findings

More than one-third of the workers had reported poor sleep quality. Results from multivariable logistic regression analysis yielded male gender (OR = 2.74, 95% CI 1.46–5.17), alcohol drinking (OR=2.1, 95% CI 1.24–3.35), pain (OR=2.05, 95% CI 1.32–3.17) and rotating shift work (OR=1.94, 95% CI 1.23–3.05) increased the risk of poor sleep quality. Furthermore, poor sleep quality was statistically significantly associated with the risk of work-related injuries (OR = 3.98, 95% CI = 2.39–6.66).

Originality/value

Findings of this study indicate that the prevalence of poor sleep quality is high among industrial workers. Work characteristics and health behaviors were associated with poor sleep quality which increases the risk of work-related injuries. Modification of work environment and personal life style choices can improve quality of sleep among workers and consequently lower incidence of work-related injuries.

Sleep problems and fatigue as predictors for the onset of chronic widespread pain over a 5- and 18-year perspective

BACKGROUND

Previous research suggests that sleep problems may be an important predictor for chronic widespread pain (CWP). With this study we investigated both sleep problems and fatigue as predictors for the onset of CWP over a 5-year and an 18-year perspective in a population free from CWP at baseline.

METHODS

To get a more stable classification of CWP, we used a wash-out period, including only individuals who had not reported CWP at baseline (1998) and three years prior baseline (1995). In all, data from 1249 individuals entered the analyses for the 5-year follow-up and 791 entered for the 18-year follow-up. Difficulties initiating sleep, maintaining sleep, early morning awakening, non-restorative sleep and fatigue were investigated as predictors separately and simultaneously in binary logistic regression analyses.

RESULTS

The results showed that problems with initiating sleep, maintaining sleep, early awakening and non-restorative sleep predicted the onset of CWP over a 5-year (OR 1.85 to OR 2.27) and 18-year (OR 1.54 to OR 2.25) perspective irrespective of mental health (assessed by SF-36) at baseline. Also fatigue predicted the onset of CWP over the two-time perspectives (OR 3.70 and OR 2.36 respectively) when adjusting for mental health. Overall the effect of the sleep problems and fatigue on new onset CWP (over a 5-year perspective) was somewhat attenuated when adjusting for pain at baseline but remained significant for problems with early awakening, non-restorative sleep and fatigue. Problems with maintaining sleep predicted CWP 18 years later irrespective of mental health and number of pain regions (OR 1.72). Reporting simultaneous problems with all four aspects of sleep was associated with the onset of CWP over a five-year and 18-yearperspective, irrespective of age, gender, socio economy, mental health and pain at baseline. Sleep problems and fatigue predicted the onset of CWP five years later irrespective of each other.

CONCLUSION

Sleep problems and fatigue were both important predictors for the onset of CWP over a five-year perspective. Sleep problems was a stronger predictor in a longer time-perspective. The results highlight the importance of the assessment of sleep quality and fatigue in the clinic.

Sleep quality and covariates as predictors of pain intensity among the general population in rural China

Purpose

The aims of this study were to investigate the distribution of sleep quality and its relationship with the prevalence of pain among rural Chinese people and to explore the association between sleep quality and pain intensity among the general population in real-life settings.

Methods

This cross-sectional survey included a total of 2052 adults from rural areas in Liuyang, Hunan Province, recruited through random multistage sampling. The distributions of sleep quality and pain prevalence among the participants over a 4-week period were described. Because of multicollinearity among variables, the influence of self-rated sleep quality and psychosocial covariates on pain intensity was explored using a ridge regression model.

Results

The data showed that participants reporting all categories of sleep quality experienced some degree of pain. Sleep quality, along with physical and mental health, was a negative predictor of pain intensity among the general population. Symptoms of depression positively predicted pain intensity.

Conclusion

Poor sleep quality increased pain intensity among the participants. Both previous research and the present data suggest that improving sleep quality may significantly decrease pain intensity in the general population. The relationship between sleep and pain may be bidirectional. This finding also suggests that treatment for sleep disorders and insomnia should be addressed in future efforts to alleviate pain intensity.

The role of emotion regulation in chronic pain: A systematic literature review

OBJECTIVE

Emotion regulation (ER) includes a set of cognitive and attentional processes used to change or maintain emotional state. A small but growing body of research suggests that maladaptive ER might be a risk factor for the development of chronic pain. This review aims to summarize existing literature on the association between ER and chronic pain, and to determine whether the construct of ER may further enhance our understanding of the risk and protective factors that may contribute to the onset and maintenance of chronic pain.

METHODS

A systematic search was conducted using the search terms "chronic pain" and "emotion regulation." Studies that measured both constructs across all age groups were included.

RESULTS

We found 15 studies that met our inclusion criteria. Nine studies were completed within the last five years, suggesting that the evaluation of ER as it relates to pain is a new line of research. Studies that measured "response-focused" ER found associations between maladaptive ER and pain. Studies that measured "antecedent-focused" ER strategies were less likely to show a direct association with pain.

CONCLUSION

Maladaptive response-focused ER may be an important risk factor in the development and maintenance of chronic pain, as it is associated with pain and psychological comorbidities. Adding ER to chronic pain investigations may help to further explain individual differences in the risk and protective mechanisms that are known to influence chronic pain. Importantly, this line of research has potential to directly inform future interventions for patients with chronic pain.

Individual Variation in Pain Sensitivity and Conditioned Pain Modulation in Acute Low Back Pain: Effect of Stimulus Type, Sleep, and Psychological and Lifestyle Factors

Generalized hyperalgesia and impaired pain modulation are reported in chronic low back pain (LBP). Few studies have tested whether these features are present in the acute phase. This study aimed to test for differences in pain presentation in early-acute LBP and evaluate the potential contribution of other factors to variation in sensitivity. Individuals within 2 weeks of onset of acute LBP (n = 126) and pain-free controls (n = 74) completed questionnaires related to their pain, disability, behavior, and psychological status before undergoing conditioned pain modulation (CPM) and pain threshold (heat, cold, and pressure) testing at the back and forearm/thumb. LBP participants were more sensitive to heat and cold at both sites and pressure at the back than controls, without differences in CPM. Only those with high-pain (numeric rating scale ≥4) were more sensitive to heat at the forearm and pressure at the back. Four subgroups with distinct features were identified: "high sensitivity," "low CPM efficacy," "high sensitivity/low CPM efficacy," and "low sensitivity/high CPM efficacy." Various factors such as sleep and alcohol were associated with each pain measure. Results provide evidence for generalized hyperalgesia in many, but not all, individuals during acute LBP, with variation accounted for by several factors. Specific pain phenotypes provide candidate features to test in longitudinal studies of LBP outcome.

PERSPECTIVE

Sensory changes indicative of increased/decreased central processing of pain and nociceptive input presented differently between individuals with acute LBP and were related to factors such as sleep and alcohol. This may underlie variation in outcome and suggest potential for early identification of individuals with poor long-term outcome.

The association between pain and sleep in fibromyalgia

OBJECTIVE

To clarify the association between pain and sleep in fibromyalgia.  Methods: Electronic databases, including PsycINFO, the Cochrane database for systematic reviews, PubMed, EMBASE, and Ovid were searched to identify eligible articles. Databases independently screened and  the quality of evidence using a reliable and valid quality assessment tool was assessed.  Results: In total, 16 quantitative studies fulfilled the inclusion criteria. According to the results, increased pain in fibromyalgia was associated with reduced sleep quality, efficiency, and duration and increased sleep disturbance and onset latency and total wake time. Remarkably, depressive symptoms were also related to both pain and sleep in patients with fibromyalgia.   Conclusion: Management strategies should be  developed to decrease pain while increasing sleep quality in patients with fibromyalgia. Future studies should also consider mood disorders and emotional dysfunction, as comorbid conditions could occur with both pain and sleep disorder in fibromyalgia.

Fibromyalgia: A Critical and Comprehensive Review

Fibromyalgia is a disorder that is part of a spectrum of syndromes that lack precise classification. It is often considered as part of the global overview of functional somatic syndromes that are otherwise medically unexplained or part of a somatization disorder. Patients with fibromyalgia share symptoms with other functional somatic problems, including issues of myalgias, arthralgias, fatigue and sleep disturbances. Indeed, there is often diagnostic and classification overlap for the case definitions of a variety of somatization disorders. Fibromyalgia, however, is a critically important syndrome for physicians and scientists to be aware of. Patients should be taken very seriously and provided optimal care. Although inflammatory, infectious, and autoimmune disorders have all been ascribed to be etiological events in the development of fibromyalgia, there is very little data to support such a thesis. Many of these disorders are associated with depression and anxiety and may even be part of what has been sometimes called affected spectrum disorders. There is no evidence that physical trauma, i.e., automobile accidents, is associated with the development or exacerbation of fibromyalgia. Treatment should be placed on education, patient support, physical therapy, nutrition, and exercise, including the use of drugs that are approved for the treatment of fibromyalgia. Treatment should not include opiates and patients should not become poly pharmacies in which the treatment itself can lead to significant morbidities. Patients with fibromyalgia are living and not dying of this disorder and positive outlooks and family support are key elements in the management of patients.

Exploring the associations shared by mood, pain-related attention and pain outcomes related to sleep disturbance in a chronic pain sample

OBJECTIVE

Sleep disturbance in chronic pain is common, occurring in two-thirds of patients. There is a complex relationship between chronic pain and sleep; pain can disrupt sleep and poor sleep can exaggerate pain intensity. This may have an impact on both depressive symptoms and attention to pain. This study aims to evaluate the relationship between chronic pain and sleep, and the role of mood and attention.

METHODS

Chronic pain patients, recruited from a secondary care outpatient clinic, completed self-report measures of pain, sleep, depressive symptoms and attention to pain. Hierarchical regression and structural equation modelling were used to explore the relationships between these measures. Participants (n = 221) were aged between 20 and 84 (mean = 52) years.

RESULTS

The majority of participants were found to be 'poor sleepers' (86%) with increased pain severity, depressive symptoms and attention to pain. Both analytical approaches indicated that sleep disturbance is indirectly associated with increased pain severity Instead the relationship shared by sleep disturbance and pain severity was further associated with depressive symptoms and attention to pain.

CONCLUSIONS

Our results indicate that sleep disturbance may contribute to clinical pain severity indirectly though changes in mood and attention. Prospective studies exploring lagged associations between these constructs could have critical information relevant to the treatment of chronic pain.

A multilevel path model analysis of the relations between sleep, pain, and pain catastrophizing in chronic pain rehabilitation patients

BACKGROUND AND AIM

Pain catastrophizing is linked to heightened pain and poorer coping among individuals with chronic pain, yet little is known about how pain catastrophizing associates with sleep and pain over the course of treatment for chronic pain. Previous research employing a cross-sectional design suggests that sleep mediates the association between pain catstrophizing and pain, but there have been no longitudinal studies examining the directionality of these associations. Thus, the aim of this study was to test two competing theoretical models. The first model specified that pain catastrophizing leads to increased pain via poor sleep. The second model specified that poor sleep leads to increased pain catastrophizing via increased pain.

METHODS

This study examined the relations between pain catastrophizing, sleep, and pain among 50 consecutive patients (36 female, 14 male) ages 20-80 (M=45.96, SD=13.94) with chronic, non-malignant pain who were admitted to the Cleveland Clinic, Chronic Pain Rehabilitation Programme (CPRP). The CPRP, within the Neurological Centre for Restoration, Neurologic Institute at the Cleveland Clinic, is a comprehensive, interdisciplinary programme designed to treat patients with disabling chronic pain. As part of their daily, morning update with their case manager, patients completed self-report ratings of their previous night's sleep time (TST), and their current pain, anxiety, and depression. Pain catastrophizing was assessed at admission and discharge.

RESULTS

Over the course of treatment, daily TST increased from approximately 5h and 20min per night to nearly 6h and 30min per night, and average daily pain, daily depression, and daily anxiety decreased over the course of treatment. As the data in this study has a multilevel structure, with daily reports nested with in patients, we conducted multilevel path models to examine the longitudinal relations between pain catastrophizing, sleep, and pain. Multilevel path analysis permits the analysis of interdependent data without violating the assumptions of standard multiple regression. Models were conducted for pain catastrophizing and each of its subscales: rumination, magnification and helplessness. The findings were uniform across the composite pain catastrophizing scale and its subscales. There was an indirect path from sleep to pain catastrophizing (post-treatment) via pain, but not from pain catastrophizing (pre-treatment) to pain via sleep. There were also direct effects of sleep on pain and from pain to pain catastrophizing (post-treatment). Additionally, decreases in pain over the course of treatment were related to lower pain catastrophizing post-treatment.

CONCLUSION AND IMPLICATIONS

These results call into question previous evidence that pain catastrophizing indirectly affects pain by way of its impact on sleep. Rather, our findings suggest that pain mediates the relationship between sleep and levels of pain catastrophizing. These results therefore underscore importance and value in collecting longitudinal data and potential influence on the conclusions gained with regards to sleep, pain and psychological variables. These findings may be of clinical importance when tailoring interventions for individuals with chronic pain and perhaps even more so for those with comorbid pain and sleep disturbance; prioritizing the treatment of sleep difficulties could result in improvements to pain-related outcomes.

The association of sleep and pain: an update and a path forward

Ample evidence suggests that sleep and pain are related. However, many questions remain about the direction of causality in their association, as well as mechanisms that may account for their association. The prevailing view has generally been that they are reciprocally related. The present review critically examines the recent prospective and experimental literature (2005-present) in an attempt to update the field on emergent themes pertaining to the directionality and mechanisms of the association of sleep and pain. A key trend emerging from population-based longitudinal studies is that sleep impairments reliably predict new incidents and exacerbations of chronic pain. Microlongitudinal studies employing deep subjective and objective assessments of pain and sleep support the notion that sleep impairments are a stronger, more reliable predictor of pain than pain is of sleep impairments. Recent experimental studies suggest that sleep disturbance may impair key processes that contribute to the development and maintenance of chronic pain, including endogenous pain inhibition and joint pain. Several biopsychosocial targets for future mechanistic research on sleep and pain are discussed, including dopamine and opioid systems, positive and negative affect, and sociodemographic factors.

PERSPECTIVE

This critical review examines the recent prospective and experimental research (2005-present) on the association of sleep and pain in an attempt to identify trends suggestive of directionality and potential mechanisms. An update on this literature is needed to guide future clinical efforts to develop and augment treatments for chronic sleep disturbance and chronic pain.