A Critical Review of Neurobiological Factors Involved in the Interactions Between Chronic Pain, Depression, and Sleep Disruption

Pain-Insomnia-Depression Syndrome: Triangular Relationships, Pathobiological Correlations, Current Treatment Modalities, and Future Direction

Pain-insomnia-depression syndrome (PIDS) is a complex triad of chronic pain, insomnia, and depression that has profound effects on an individual's quality of life and mental health. The pathobiological context of PIDS involves complex neurobiological and physiological mechanisms, including alterations in neurotransmitter systems and impaired pain processing pathways. The first-line therapeutic approaches for the treatment of chronic pain, depression, and insomnia are a combination of pharmacological and non-pharmacological therapies. In cases where patients do not respond adequately to these treatments, additional interventions such as deep brain stimulation (DBS) may be required. Despite advances in understanding and treatment, there are still gaps in knowledge that need to be addressed. To improve our understanding, future research should focus on conducting longitudinal studies to uncover temporal associations, identify biomarkers and genetic markers associated with PIDS, examine the influence of psychosocial factors on treatment responses, and develop innovative interventions that address the complex nature of PIDS. The aim of this study is to provide a comprehensive overview of these components and to discuss their underlying pathobiological relationships.

Hemorrhoids are associated with an increased risk of depression in Germany: A retrospective cohort study in primary care outpatients

BACKGROUND

The aim of the present study was to analyze the cumulative incidence of depression diagnosis in patients with hemorrhoids and to evaluate the association between hemorrhoids and subsequent depression diagnosis.

METHODS

This retrospective cohort study was based on electronic medical records from the Disease Analyzer database (IQVIA) and included 87,264 individuals with hemorrhoids (mean age: 54.2 years; 42% women) and 87,264 propensity score-matched individuals without hemorrhoids in 1284 general practices in Germany between January 2005 and December 2021. Univariable Cox regression analysis was conducted to assess the association between hemorrhoids and depression.

RESULTS

After up to 10 years of follow-up, 21.4% of patients with hemorrhoids versus 16.3% of the matched cohort (p < 0.001) were diagnosed with depression. There was a significant association between hemorrhoids and a subsequent diagnosis of depression (HR: 1.32; 95% CI: 1.28-1.37), which was confirmed in age- and sex-stratified analyses. The association was stronger with increasing degree of hemorrhoids, from HR: 1.29 (95% CI: 1.15-1.45) for Grade 1 to HR: 1.73 (95% CI: 1.11-2.69) for Grade 4 compared to no hemorrhoids.

CONCLUSIONS

The present study provides compelling evidence of an association between hemorrhoids and subsequent depression. Addressing the mental health of individuals with hemorrhoids may not only improve their overall well-being but could also lead to better treatment outcomes for the primary condition.

Understanding Predictors of Fatigue Over Time in Persons With Inflammatory Bowel Disease: The Importance of Depressive and Anxiety Symptoms

INTRODUCTION

Fatigue is a complex and frequent symptom in persons with inflammatory bowel disease (IBD), with detrimental impact. We aimed to determine predictors of fatigue over time.

METHODS

Two hundred forty-seven adults with IBD participated in a prospective study conducted in Manitoba, Canada, providing data at baseline and annually for 3 years. Participants reported fatigue impact (Daily Fatigue Impact Scale [DFIS]), depression and anxiety symptoms (Hospital Anxiety and Depression Scale [HADS]), and pain (Pain Effects Scale [PES]). Physician-diagnosed comorbidities, IBD characteristics, and physical and cognitive functioning were also assessed. We tested factors associated with fatigue using multivariable generalized linear models that estimated within-person and between-person effects.

RESULTS

Most participants were women (63.2%), White (85.4%), and had Crohn's disease (62%). At baseline, 27.9% reported moderate-severe fatigue impact, 16.7% had clinically elevated anxiety (HADS-A ≥11), and 6.5% had clinically elevated depression (HADS-D ≥11). Overall fatigue burden was stable over time, although approximately half the participants showed improved or worsening fatigue impact between annual visits during the study. On multivariable analysis, participants with a one-point higher HADS-D score had, on average, a 0.63-point higher DFIS score, whereas participants with a one-point higher PES score had a 0.78-point higher DFIS score. Within individuals, a one-point increase in HADS-D scores was associated with 0.61-point higher DFIS scores, in HADS-A scores with 0.23-point higher DFIS scores, and in PES scores with 0.38-point higher DFIS scores. No other variables predicted fatigue.

DISCUSSION

Anxiety, depression, and pain predicted fatigue impact over time in IBD, suggesting that targeting psychological factors and pain for intervention may lessen fatigue burden.

Investigating a clinically informed sleep disturbance threshold for physical and mental health among Gulf War Illness veterans

Study Objectives

This study (1) assessed sleep quality and health in Gulf War veterans (GWV) meeting the Gulf War Illness (GWI) criteria and (2) compared health associations for both those meeting a "clinically disturbed sleep" threshold, and those below, as determined by the Pittsburgh Sleep Quality Index (PSQI) cutoff for military populations (≥10) on measures of physical, mental, and cognitive health.

Methods

Participant data consisted of questionnaires and assessments completed prior to group assignment in a clinical trial. The sample consisted of 147 GWV, where 81.0% were males, and the median age was 53.4 years.

Results

The mean (SD) PSQI global score was 12.34 (4.00) with 61% of the sample qualifying as clinically disturbed sleepers according to the cutoff (global PSQI ≥ 10). GWI veterans with PSQI scores ≥10 did not differ from others in age (p = 0.20), sex (p = 0.19), or years of education (p = 0.87), but showed worse GW-related symptomology on the Gulf War Kansas questionnaire (p < 0.01), and poorer mental health on the Veterans Rand-36 (p < 0.01).

Conclusions

Disturbed sleep was associated with measures of pain, fatigue, and cognitive health. Our results suggest that a previously determined clinical threshold for clinically disturbed sleep is useful when examining the health status of the study population. Given that GWI is associated with elevated PSQI scores and a high frequency of disturbed sleep, cutoffs determining sleep health should be sensitive to population exposures and health history to improve interpretability.

Systemic Inflammation, Sleep, and Psychological Factors Determine Recovery Trajectories for People With Neck Pain: An Exploratory Study

We conducted an explorative prospective cohort study with 6 months follow-up to 1) identify different pain and disability trajectories following an episode of acute neck pain, and 2) assess whether neuroimmune/endocrine, psychological, behavioral, nociceptive processing, clinical outcome, demographic and management-related factors differ between these trajectories. Fifty people with acute neck pain (ie, within 2 weeks of onset) were included. At baseline, and at 2, 4, 6, 12, and 26 weeks follow-up, various neuroimmune/endocrine (eg, inflammatory cytokines and endocrine factors), psychological (eg, stress symptoms), behavioral (eg, sleep disturbances), nociceptive processing (eg, condition pain modulation), clinical outcome (eg, trauma), demographic factors (eg, age), and management-related factors (eg, treatment received) were assessed. Latent class models were performed to identify outcome trajectories for neck pain and disability. Linear mixed models or the Pearson chi-square test were used to evaluate differences in these factors between the trajectories at baseline and at each follow-up assessment and over the entire 6 months period. For pain, 3 trajectories were identified. The majority of patients were assigned to the "Moderate pain - Favourable recovery" trajectory (n = 25; 50%) with smaller proportions assigned to the "Severe pain - Favourable recovery" (n = 16; 32%) and the "Severe pain - Unfavourable recovery" (n = 9; 18%) trajectories. For disability, 2 trajectories were identified: "Mild disability - Favourable recovery" (n = 43; 82%) and "Severe disability - Unfavourable recovery" (n = 7; 18%). Ongoing systemic inflammation (increased high-sensitive C-reactive protein), sleep disturbances, and elevated psychological factors (such as depression, stress and anxiety symptoms) were mainly present in the unfavorable outcome trajectories compared to the favorable outcome trajectories. PERSPECTIVE: Using exploratory analyses, different recovery trajectories for acute neck pain were identified based on disability and pain intensity. These trajectories were influenced by systemic inflammation, sleep disturbances, and psychological factors.

Effects of Nature-Based Multisensory Stimulation on Pain Mechanisms in Women with Fibromyalgia Syndrome: A Randomized Double-Blind Placebo-Controlled Trial

BACKGROUND

The term "nature-based sensory stimuli" refers to the sensory information produced by biotic and abiotic agents from natural environments. The literature has reported the beneficial effects of these agents on various pain dimensions in non-clinical populations.

AIMS

To evaluate the potential analgesic effects of nature-based multisensory stimulation in women with fibromyalgia syndrome.

METHODS

A randomized, double-blind, placebo-controlled, parallel-group trial with a 1:1 allocation ratio was conducted. Forty-two women with fibromyalgia syndrome interacted with either different plant species with flowers, stones, and soil organic matter or their synthetic imitations for 30 minutes. Outcome measurements were performed before and after the intervention, including clinical pain intensity using the Numeric Rating Scale, cold pain thresholds using the Cold Pressor Test, mechanical hyperalgesia and wind-up using a monofilament, and pressure pain thresholds using a pressure algometer.

RESULTS

Analyses revealed group × time interactions for clinical pain intensity (F = 7.915, p = .008), cold-water immersion time (F = 7.271, p = .010), mechanical hyperalgesia (F = 4.701, p = .036), and pressure pain threshold (p ≤ .017). Between-group differences were found in clinical pain intensity (p = .012), cold pain thresholds (p = .002), and pressure pain thresholds (p < .05). The experimental group exhibited reduced clinical pain intensity (p = .001) and increased pressure pain thresholds (p ≤ .034).

CONCLUSIONS

Women with fibromyalgia syndrome may benefit from multisensory stimulation using biotic and abiotic agents from natural environments for 30 minutes. Interacting with flowering plants and soil components appears to induce analgesic effects.

Treating persistent pain after breast cancer: practice gaps and future directions

This paper discusses the growing problem of persisting pain after successful treatment of breast cancer and presents recommendations for improving pain-related outcomes for this group. We discuss the dominant treatment approach for persisting pain post-breast cancer treatment and draw contrasts with contemporary treatment approaches to persistent pain in non-cancer-related populations. We discuss modern application of the biopsychosocial model of pain and the notion of variable sensitivity within the pain system, moment by moment and over time. We present the implications of increasing sensitivity over time for treatment selection and implementation. By drawing on transformative changes in treatment approaches to persistent non-cancer-related pain, we describe the potentially powerful role that an intervention called pain science education, which is now recommended in clinical guidelines for musculoskeletal pain, may play in improving pain and disability outcomes after successful breast cancer treatment. Finally, we present several research recommendations that centre around adaptation of the content and delivery models of contemporary pain science education, to the post-breast cancer context.

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.

Do sleep disruptions promote social fragmentation?

Sleep changes predate shifts in mood/affect, thought processing, mental and physical health, civic engagement, and contextual circumstances, among other things. Theory predicts that these changes may lead to shifts in political and social beliefs. Do sleep disruptions shape how individuals see the world, the people around them, and themselves in relation to others? In this article, we use daily survey data from the 77 waves (N ≈ 460,000) of the University of California, Los Angeles's 2019-2021 Nationscape Survey-a nationally representative political survey-to examine the effect of an exogenous short-term sleep disruption on measures of political views, polarization, and discriminatory beliefs. Using this data set, we leverage the modest sleep disruption that occurs at the start (and end) of Daylight Saving Time (DST) and employ a regression discontinuity in time design around the precise DST cutoff (which we supplement with event study models). Despite strong theoretical expectations and correlational connection between measures of sleep and many outcomes related to social fragmentation, we find that the DST change has little to no causal effect on citizens' levels of polarization or their discriminatory attitudes. These effects are precise enough to rule out small effects, robust to a host of specification checks, and consistent across potential subgroups of interest. Our work adds to a small but growing body of research on the social and political effects of sleep disruptions.

Latent patterns of sleep disturbance, pain impact, and depressive symptoms in residential substance use treatment

AIM

Sleep disturbance, clinically significant pain, and depressive symptoms commonly occur together among individuals with substance use disorders. The purposes of the present study were to 1) identify subgroups of individuals with heterogenous patterns of pain, sleep disturbance, and depressive symptoms, and 2) identify demographic and clinical correlates of profile membership.

MATERIAL AND METHODS

The present study assessed a sample (N = 8621) of individuals seeking residential substance use treatment in 2020 and 2021 in the United States. We examined whether unique sub-groups could be identified based on patterns of sleep disturbance, pain impact, and depressive symptoms during the first four weeks of treatment, using longitudinal latent profile analysis. Next, we explored demographic, substance use, and clinical correlates (i.e., distress intolerance) of profile membership, as well as whether profile membership was associated with treatment attrition.

RESULTS

The identified classes were: 1) Low sleep disturbance, pain impact, and depressive symptoms, 2) High pain, remitting depressive symptoms, and mild sleep disturbance, 3) High depressive symptoms, low pain, and remitting sleep disturbance, and 4) High sleep disturbance, pain impact, and depressive symptoms. Individuals with high pain, depressive symptoms, and sleep disturbance were more likely to be older, use opioids as their primary substance, have high distress intolerance, and discontinue treatment.

CONCLUSION

Results highlight the importance of comprehensive care and management of physical health conditions, particularly among older adults. Further, results highlight that distress intolerance may be a modifiable risk factor for co-occurring sleep disturbance, pain impact, and depressive symptoms.

The role of co-occurring insomnia and mental distress in the association between lumbar disc degeneration and low back pain related disability

BACKGROUND

Lumbar disc degeneration (LDD) is associated with low back pain (LBP). Although both insomnia and mental distress appear to influence the pain experience, their role in the association between LDD and LBP is uncertain. Our objective was to investigate the role of co-occurring insomnia and mental distress in the association between LDD and LBP-related disability.

METHODS

A total of 1080 individuals who had experienced LBP during the previous year underwent 1.5-T lumbar magnetic resonance imaging, responded to questionnaires, and participated in a clinical examination at the age of 47. Full data was available for 843 individuals. The presence of LBP and LBP-related disability (numerical rating scale, range 0-10) were assessed using a questionnaire. LDD was assessed by a Pfirrmann-based sum score (range 0-15, higher values indicating higher LDD). The role of insomnia (according to the five-item Athens Insomnia Scale) and mental distress (according to the Hopkins Symptom Check List-25) in the association between the LDD sum score and LBP-related disability was analyzed using linear regression with adjustments for sex, smoking, body mass index, education, leisure-time physical activity, occupational physical exposure, Modic changes, and disc herniations.

RESULTS

A positive association between LDD and LBP-related disability was observed among those with absence of both mental distress and insomnia (adjusted B = 0.132, 95% CI = 0.028-0.236, p = 0.013), and among those with either isolated mental distress (B = 0.345 CI = 0.039-0.650, p = 0.028) or isolated insomnia (B = 0.207, CI = 0.040-0.373, p = 0.015). However, among individuals with co-occurring insomnia and mental distress, the association was not significant (B = -0.093, CI = -0.346-0.161, p = 0.470).

CONCLUSIONS

LDD does not associate with LBP-related disability when insomnia and mental distress co-occur. This finding may be useful when planning treatment and rehabilitation that aim to reduce disability among individuals with LDD and LBP. Future prospective research is warranted.

Possible Neuropathic Pain in Clinical Practice-Review on Selected Diagnostic Tools and Its Further Challenges

BACKGROUND

Neuropathic pain (NeP) is a wide group of conditions provoked by many different causes and with different patterns. The creation of a grading system was intended to determine the level of certainty that the pain is of neuropathic nature.

METHODS

The aim of this review is to update previously published data on some NeP questionnaires and their measurement properties. The selection of articles is based on the basic neurological units. To assess the usefulness and credibility of the questionnaires, the authors searched for a commonly used measure of reliability, as well as sensitivity and specificity.

RESULTS

Studies regarding the usefulness and credibility of questionnaires used in NeP were realized. Different patient cohorts, etiologies and sample sizes, do not allow for an unambiguous comparison of the presented scales; however, all of these studies found good measures of reliability, specificity and sensitivity.

CONCLUSIONS

NeP tools seem to be beneficial screening instruments that should be utilized by specialists and general practitioners to improve the recognition of "possible" NeP and to determine the epidemiology of this disorder. They have been developed to distinguish perceived pain into neuropathic and non-neuropathic, and, therefore, patients with a mixed pain can still present a diagnostic challenge. Clinical examination and interview play an essential role in the diagnostic process and monitoring, and cannot be neglected.

Associations of poor sleep quality, chronic pain and depressive symptoms with frailty in older patients: is there a sex difference?

Background

Sleep disturbance, chronic pain and depressive symptoms later in life are modifiable risk factors and may contribute to frailty. However, much less is known about sex differences in the association between these concurrent symptoms and frailty in older patients. Therefore, we conducted this study to explore the associations of poor sleep quality, chronic pain, and depressive symptoms with frailty in older patients, and the sex-specific associations.

Methods

In an observational population-based study, 540 older hospitalized patients from Zhejiang Hospital in China were enrolled. We collected data on poor sleep quality, pain, depressive symptoms and frailty using the Pittsburgh Sleep Quality Index, the Numerical Rating Scale, the 15-item Geriatric Depression Scale, and the Clinical Frailty Scale. Multivariate logistic regression models were used to explore the total sample and sex-specific associations among symptom burdens, symptom combination patterns and symptom counts, and frailty.

Results

After adjusting for the potential covariates, concurrent poor sleep quality and depressive symptoms (OR = 4.02, 95% CI 1.57–10.26), concurrent poor sleep quality and chronic pain (OR = 2.05, 95% CI 1.04–4.05), and having three symptoms (OR = 3.52, 95% CI 1.19–10.44) were associated with a higher likelihood of frailty in older inpatients. In addition, older patients with 2 or 3 symptoms (2 and 3 vs. 0 symptoms) had a higher risk of frailty, and the odds ratios were 2.40 and 3.51, respectively. Interaction analysis and sex-stratified associations exhibited conflicting results. The nonsignificant effect of the interaction of sex and symptoms on frailty, but not the sex-stratified associations, showed that individual symptoms, symptom combination patterns, and symptom counts were associated with elevated risks of frailty in older male patients, but not in older female patients.

Conclusions

Increased symptom burdens were associated with a higher risk of frailty in older inpatients, especially in those with poor sleep quality concurrent with at least one of the other two symptoms. Thus, a multidisciplinary program addressing these common symptoms is required to reduce adverse outcomes.

The Influence of Sleep Disturbance on Chronic Pain

PURPOSE OF REVIEW

The purpose of this review is to present an overview of common sleep disturbance pathologies and their impact on chronic pain, while examining various factors that are implicit in the relationship between sleep disturbance and chronic pain, including neurobiochemistry, anatomy, and systemic mediators, and reviewing recent and landmark literature.

RECENT FINDINGS

Earlier literature reviews and studies have introduced the bidirectional relationship between sleep disturbance and chronic pain; that is, impaired sleep may worsen chronic pain, and chronic pain causes sleep disturbance. However, more recent reviews and studies seem to show a more associative, rather than causative relationship. There have been recent studies that attempt to determine mechanisms that link sleep disturbance and chronic pain; the results of these studies were more varied, ultimately concluding that there may be a separate, yet-to-be discovered mechanism that shows the causative relationship between sleep disturbance and pain. There are several neurotransmitters that are involved in the mediation of chronic pain and sleep disturbance as separate entities, and some studies have shown that there may be mechanisms that govern both chronic pain and sleep disturbance as a single unit. Other neuroendocrine substances also serve to mediate chronic pain and sleep disturbance. All these substances are found to be associated with various sleep disorders and are also associated with chronic pain symptoms as well. Inflammation plays a role in chronic pain and sleep disturbance, with an increase in inflammatory substances and mediators associated with an increase or worsening in chronic pain symptoms and sleep disorders. The HPA axis plays a role in chronic pain and sleep disorders, influencing pain and sleep pathways through stress response, inflammation, and maintenance of homeostasis. There are several variables that influence both chronic pain and sleep disturbance, and more research into these variables may further our understanding into the complex pathways governing the influence of sleep disturbance on pain, and ultimately to improve treatment for this issue.

The association between physical activity and sleep during pregnancy: a systematic review

OBJECTIVES

Pregnant women frequently report experiencing poor sleep. Poor sleep during pregnancy is associated with negative health outcomes for both mother and baby. Physical activity (PA), including exercise may be an effective non-pharmacological strategy for improving sleep during pregnancy. The aim of this systematic review was to synthesize the current literature on the association between physical activity (including exercise) and sleep during pregnancy.

METHOD

A systematic online search was undertaken between 15-16 February 2022 in PsycINFO, CINAHL, Embase and PubMed. To meet the inclusion criteria articles had to; [1] be published in a peer reviewed journal; [2] consist of pregnant participants; and [3] be published in English. Studies were excluded if they were not published in English and did not investigate the association between a type of physical activity (including exercise) and a sleep variable during a trimester of pregnancy.

RESULTS

Ten studies were included in this review. Five of the ten studies used observational data collection measures and the remaining five used intervention based methods. Eight of the ten included studies found PA (including exercise) was positively associated with sleep during pregnancy.

CONCLUSION

In order to properly establish PA as a strategy to improve sleep during pregnancy, future research should aim to determine the PA characteristics most beneficial to sleep during pregnancy across each trimester.

Independent and combined associations of depressive symptoms and sleep disturbance with chronic pain in community-dwelling older adults

Supplemental Digital Content is Available in the Text.

The combination of depressive symptoms and sleep disturbance was positively associated with chronic pain, but there were no additive interactions in community-dwelling older adults.

Introduction:

There is limited evidence regarding whether depressive symptoms and sleep disturbance are independently or synergistically associated with chronic pain.

Objectives:

We investigated the independent and combined associations of depressive symptoms and sleep disturbance with chronic pain and its severity (and the additive interactions) in community-dwelling older adults.

Methods:

This cross-sectional study analyzed the data of 1374 individuals who were 65 to 75 year old, not in need of long-term care, and completed questionnaires assessing sociodemographic factors, depressive symptoms, sleep disturbance, and chronic pain. The severity of chronic pain was assessed based on pain intensity, pain distribution, and pain type. The participants' status of depressive symptoms and sleep disturbance were categorized in the following 4 groups: neither condition, depressive symptoms alone, sleep disturbance alone, and both conditions.

Results:

Among the 1374 participants, 849 (61.8%) had chronic pain. The multivariable-adjusted odds ratios and 95% confidence intervals of the presence of chronic pain in those with depressive symptoms alone, sleep disturbance alone, and both conditions were 1.40 (0.97–2.03), 1.98 (1.41–2.78), and 2.12 (1.39–2.23), respectively, compared with the neither-condition group. Similar associations were observed for severe chronic pain. However, there were no significant additive interactions. In addition, only sleep disturbance was significantly associated with chronic pain, after adjusting for depressive symptoms.

Conclusions:

Our analyses did not reveal a synergistic effect of depressive symptoms and sleep disturbance on chronic pain and its severity, suggesting that most of the effects of depressive symptoms on chronic pain may be mediated by sleep disturbance.

Multidimensional pain phenotypes after Traumatic Brain Injury

More than 50% of individuals develop chronic pain following traumatic brain injury (TBI). Research suggests that a significant portion of post-TBI chronic pain conditions is neuropathic in nature, yet the relationship between neuropathic pain, psychological distress, and somatosensory function following TBI is not fully understood. This study evaluated neuropathic pain symptoms, psychological and somatosensory function, and psychosocial factors in individuals with TBI (TBI, N = 38). A two-step cluster analysis was used to identify phenotypes based on the Neuropathic Pain Symptom Inventory and Beck's Anxiety Inventory scores. Phenotypes were then compared on pain characteristics, psychological and somatosensory function, and psychosocial factors. Our analyses resulted in two different neuropathic pain phenotypes: (1) Moderate neuropathic pain severity and anxiety scores (MNP-AS, N = 11); and (2) mild or no neuropathic pain symptoms and anxiety scores (LNP-AS, N = 27). Furthermore, the MNP-AS group exhibited greater depression, PTSD, pain severity, and affective distress scores than the LNP-AS group. In addition, thermal somatosensory function (difference between thermal pain and perception thresholds) was significantly lower in the MNP-AS compared to the LNP-AS group. Our findings suggest that neuropathic pain symptoms are relatively common after TBI and are not only associated with greater psychosocial distress but also with abnormal function of central pain processing pathways.

Neural correlates of co-occurring pain and depression: an activation-likelihood estimation (ALE) meta-analysis and systematic review

The relationship between pain and depression is thought to be bidirectional and the underlying neurobiology 'shared' between the two conditions. However, these claims are often based on qualitative comparisons of brain regions implicated in pain or depression, while focused quantitative studies of the neurobiology of pain-depression comorbidity are lacking. Particularly, the direction of comorbidity, i.e., pain with depression vs. depression with pain, is rarely addressed. In this systematic review (PROSPERO registration CRD42020219876), we aimed to delineate brain correlates associated with primary pain with concomitant depression, primary depression with concurrent pain, and equal pain and depression comorbidity, using activation likelihood estimation (ALE) meta-analysis. Neuroimaging studies published in English until the 28th of September 2021 were evaluated using PRISMA guidelines. A total of 70 studies were included, of which 26 reported stereotactic coordinates and were analysed with ALE. All studies were assessed for quality by two authors, using the National Institute of Health Quality Assessment Tool. Our results revealed paucity of studies that directly investigated the neurobiology of pain-depression comorbidity. The ALE analysis indicated that pain with concomitant depression was associated with the right amygdala, while depression with concomitant pain was related primarily to the left dorsolateral prefrontal cortex (DLPFC). We provide evidence that pain and depression have a cumulative negative effect on a specific set of brain regions, distinct for primary diagnosis of depression vs. pain.

"I Don't Know Why I've Got this Pain!" Allostasis as a Possible Explanatory Model

Explaining the onset and maintenance of pain can be challenging in many clinical presentations. Allostasis encompasses the mechanisms through which humans adapt to stressors to maintain physiological stability. Due to related neuro-endocrine-immune system effects, allostasis and allostatic load (the cumulative effects on the brain and body that develop through the maintenance of physiological stability) offer the potential to explain the development and maintenance of musculoskeletal pain in certain cases. This paper outlines the concept of allostatic load, highlights the evidence for allostatic load in musculoskeletal pain conditions to date, and discusses mechanisms through which allostatic load influences pain, with particular focus on hypothalamic-pituitary-adrenal axis and sympathetic nervous system function and central, brain-driven governance of these systems. Finally, through case examples, consideration is given as to how allostatic load can be integrated into clinical reasoning and how it can be used to help explain pain to individuals and guide clinical decision-making.

IMPACT

Awareness of the concept of allostatic load, and subsequent assessment of physical and psychological stressors potentially contributing to allostatic load, may facilitate a broader understanding of the multidimensional presentations of many people with pain, both acute and persistent. This may facilitate discussion between clinicians and their patients regarding broader influences on their presentations and drive more targeted and inclusive pain management strategies.

Dietary Supplementation With Branched Chain Amino Acids to Improve Sleep in Veterans With Traumatic Brain Injury: A Randomized Double-Blind Placebo-Controlled Pilot and Feasibility Trial

Study Objectives

Traumatic brain injury (TBI) is associated with chronic sleep disturbances and cognitive impairment. Our prior preclinical work demonstrated dietary supplementation with branched chain amino acids (BCAA: leucine, isoleucine, and valine), precursors to de novo glutamate production, restored impairments in glutamate, orexin/hypocretin neurons, sleep, and memory in rodent models of TBI. This pilot study assessed the feasibility and preliminary efficacy of dietary supplementation with BCAA on sleep and cognition in Veterans with TBI.

Methods

Thirty-two Veterans with TBI were prospectively enrolled in a randomized, double-blinded, placebo-controlled trial comparing BCAA (30 g, b.i.d. for 21-days) with one of two placebo arms (microcrystalline cellulose or rice protein, both 30 g, b.i.d. for 21-days). Pre- and post-intervention outcomes included sleep measures (questionnaires, daily sleep/study diaries, and wrist actigraphy), neuropsychological testing, and blood-based biomarkers related to BCAA consumption.

Results

Six subjects withdrew from the study (2/group), leaving 26 remaining subjects who were highly adherent to the protocol (BCAA, 93%; rice protein, 96%; microcrystalline, 95%; actigraphy 87%). BCAA were well-tolerated with few side effects and no adverse events. BCAA significantly improved subjective insomnia symptoms and objective sleep latency and wake after sleep onset on actigraphy.

Conclusion

Dietary supplementation with BCAA is a mechanism-based, promising intervention that shows feasibility, acceptability, and preliminary efficacy to treat insomnia and objective sleep disruption in Veterans with TBI. A larger scale randomized clinical trial is warranted to further evaluate the efficacy, dosing, and duration of BCAA effects on sleep and other related outcome measures in individuals with TBI.

Clinical Trial Registration

[http://clinicaltrials.gov/], identifier [NCT03990909].

Early Optimized Pharmacological Treatment in Patients With Depression and Chronic Pain

Major depressive disorder (MDD) is the leading cause of disability worldwide. Patients with MDD have high rates of comorbidity with mental and physical conditions, one of which is chronic pain. Chronic pain conditions themselves are also associated with significant disability, and the large number of patients with MDD who have chronic pain drives high levels of disability and compounds healthcare burden. The management of depression in patients who also have chronic pain can be particularly challenging due to underlying mechanisms that are common to both conditions, and because many patients with these conditions are already taking multiple medications. For these reasons, healthcare providers may be reluctant to treat such patients. The Canadian Network for Mood and Anxiety Treatments (CANMAT) guidelines provide evidence-based recommendations for the management of MDD and comorbid psychiatric and medical conditions such as anxiety, substance use disorder, and cardiovascular disease; however, comorbid chronic pain is not addressed. In this article, we provide an overview of the pathophysiological and clinical overlap between depression and chronic pain and review evidence-based pharmacological recommendations in current treatment guidelines for MDD and for chronic pain. Based on clinical experience with MDD patients with comorbid pain, we recommend rapidly and aggressively treating depression according to CANMAT treatment guidelines, using antidepressant medications with analgesic properties, while addressing pain with first-line pharmacotherapy as treatment for depression is optimized. We review options for treating pain symptoms that remain after response to antidepressant treatment is achieved.

Caregiver-provider communication about pain in persons with dementia

BACKGROUND

Pain in older persons with dementia is both under-detected and under-managed. Family caregivers can play an important role in addressing these deficiencies by communicating their care recipient's symptoms and behaviors to medical providers, but little is known about how caregivers and providers approach pain-related discussions in the context of dementia. The goal of this study was to explore how ambulatory care providers and family caregivers of persons with dementia view pain communication.

METHODS

In-depth, semi-structured interviews were conducted with family caregivers (n = 18) and healthcare providers involved in dementia care (n = 16). Interviews focused on three specific content areas: (1) caregivers' roles in communicating about pain in persons with dementia, (2) challenges experienced when communicating about pain in persons with dementia, and (3) strategies and recommendations for optimizing communication in this context. All interviews were audio-recorded, transcribed, and analyzed using the constant comparative method of data analysis.

RESULTS

Caregivers and providers described various roles that caregivers assumed in communication processes, such as serving as historians, interpreters, and advocates. They identified two key features of problematic communication-receipt of inadequate information and interpersonal conflict about the care recipient's pain-and articulated how ambiguity around pain and dementia, as well as preexisting beliefs and emotions, contributed to communication challenges. They also offered several suggestions to improve caregiver-provider communication processes, including the use of (1) written records to enhance the accuracy of caregivers' reports and ensure that providers had specific information to inform symptom management and treatment plans, (2) pain scales and follow-up discussions to establish baseline data and clarify treatment recommendations, and (3) collaboration and rapport-building strategies to validate the caregivers' contributions and maximize a team-based decision-making.

CONCLUSION

Receipt of inadequate information and interpersonal conflict are key challenges to caregiver-provider communication regarding pain in persons with dementia. Written records, pain scales, and rapport-building strategies may help to address these challenges.

The profile of musculoskeletal pain and its associations with sleep quality and depression during the COVID-19 in Turkey

Background

The current pandemic has affected people’s health multidimensionally. This study aims to investigate musculoskeletal pain, sleep quality, depression levels, and their relationships in individuals belonging to different age groups during COVID-19 in Turkey.

Methods

A web-based self-administered survey that consisted of demographic questions, The Beck Depression Inventory (BDI), Pittsburgh Sleep Quality Index (PSQI), and scores of musculoskeletal pain was sent to participants. Pearson correlation analysis was used for determining the statistical relationship between variables.

Results

The study includes 1,778 participants. The highest percentage for mild, moderate, and severe pain was in the head (49.8%), back (15.5%), and head (11.5%), respectively. The PSQI-total had shown a weak correlation with pain levels in all body parts. The highest correlation for sleep quality and pain levels was between the PSQI-5 and lower back pain. There was a weak correlation between PSQI-2 and the BDI score, and a moderate correlation between the PSQI-1, PSQI-5, PSQI-7, PSQI-total, and BDI score. Pain in all body parts showed a weak correlation with depression level.

Conclusions

This study showed that musculoskeletal pain was varied in body parts with different intensities according to age groups in Turkey during the pandemic. The most common pain was in the head, back, and lower back. Headache was found correlated with the parameters of sleep quality. Pain of the head, neck, back, lower back, and shoulder were correlated with sleep latency. Sleep quality was associated with depression and musculoskeletal pain, while musculoskeletal pain was correlated with depression.

UK Medical Cannabis registry: an analysis of clinical outcomes of medicinal cannabis therapy for chronic pain conditions

OBJECTIVES

To explore pain-specific, general health-related quality of life (HRQoL), and safety outcomes of chronic pain patients prescribed cannabis-based medicinal products (CBMPs).

METHODS

A case series was performed using patients with chronic pain from the UK Medical Cannabis Registry. Primary outcomes were changes in Brief Pain Inventory short-form (BPI), Short-form McGill Pain Questionnaire-2 (SF-MPQ-2), Visual Analogue Scale-Pain (VAS), General Anxiety Disorder-7 (GAD-7), Sleep Quality Scale (SQS), and EQ-5D-5L, at 1, 3, and 6 months from baseline. Statistical significance was defined at p-value<0.050.

RESULTS

190 patients were included. Median initial Δ⁹-tetrahydrocannabinol and cannabidiol daily doses were 2.0mg (range:0.0-442.0mg) and 20.0mg (range:0.0-188.0mg) respectively. Significant improvements were observed within BPI, SF-MPQ-2, GAD-7, SQS, EQ-5D-5 L index, and VAS measures at all timepoints (p<0.050). Seventy-five adverse events (39.47%) were reported, of which 37 (19.47%) were rated as mild, 23 (12.11%) as moderate, and 14 (7.37%) as severe. Nausea (n=11; 5.8%) was the most frequent adverse event.

CONCLUSION

An association was identified between patients with chronic pain prescribed CBMPs and improvements in pain-specific and general HRQoL outcomes. Most adverse events were mild to moderate in severity, indicating CBMPs were well tolerated. Inherent limitations of study design limit its overall applicability.

Depressive symptoms and health-related quality of life in a heterogeneous psychiatric sample: conditional indirect effects of pain severity and interference

BACKGROUND

Few studies have examined clinically relevant mechanisms that underlie the association between two important indices of recovery- depression severity and health-related quality of life (HRQOL) in psychiatric outpatients. This study aimed to explicate the roles of pain interference and pain severity as mediating and moderating mechanisms in the relationship between depressive symptoms and HRQOL.

METHODS

Data from 290 outpatients diagnosed with schizophrenia (n = 102), depressive (n = 98), and anxiety (n = 90) disorders were examined. Participants completed a set of questionnaires that queried their sociodemographic statuses, current pain severity and interference levels, depression severity levels, and HRQOL. Subsequently, mediation and moderation analyses were conducted.

RESULTS

Analyses revealed that pain interference fully mediated the relationship between depressive symptoms and physical (34% of the total effect) but not mental HRQOL. At high pain levels (+ 1 SD from mean), depressive symptoms may interfere with physical quality of life through pain interference, but this was not present at low pain levels (- 1 SD from mean).

CONCLUSIONS

Prolonged pain symptoms could negatively influence psychiatric recovery beyond the physical aspect of HRQOL. These results thus imply a need to detect and manage severe physical pain complaints at the acute stage in psychiatric outpatients.

Somatic Symptoms and Sleep Disorders: A Literature Review of Their Relationship, Comorbidities and Treatment

This study aimed to investigate the relationship between somatic symptom disorder (SSD) and sleep disorders, following three research questions: (1) How are these disorders correlated? (2) What are the comorbidities reported in these patients? and (3) What are the most effective pharmacological and non-pharmacological treatments for both conditions? PubMed, Scopus, OVID, Medline, and ProQuest databases were searched for relevant articles published between 1957–2020. Search terms included “somatic symptoms disorder”, “sleep disorders”, “insomnia”, “somatoform”, “somatization”, “therapeutic”, “psychotherapy”, and alternative, formerly used terms for SSD. Forty papers were finally included in the study. Prevalence of insomnia in SSD patients ranged between 20.4–48%, with this being strongly correlated to somatic symptoms and psychosocial disability. The most relevant comorbidities were generalized anxiety disorder, depression, fatigue, negative mood, substance use, orthorexia, alexithymia, anorexia, weight loss, poor eating habits, and acute stress disorder. Patients receiving antidepressant therapy reported significant improvements in insomnia and somatic symptoms. In terms of non-pharmacological interventions, cognitive-behavioral therapy (CBT) showed improvements in sleep outcomes, while the Specialized Treatment for Severe Bodily Distress Syndromes (STreSS) may represent an additional promising option. Future research could include other medical and psychosocial variables to complete the picture of the relationship between sleep disorders and somatic symptoms.

Kappa opioid receptor modulation of endometriosis pain in mice

The kappa opioid receptor is a constituent of the endogenous opioid analgesia system widely expressed in somatosensory nervous pathways and also in endometrial tissues. This work investigates the possible involvement of kappa opioid receptor on the nociceptive, behavioral and histopathological manifestations of endometriosis in a murine model. Female mice receiving endometrial implants develop a persistent mechanical hypersensitivity in the pelvic area that is stronger during the estrus phase of the estrous cycle. The kappa opioid receptor agonist U50,488H produces a dose-dependent relief of this mechanical hypersensitivity, regardless of the cycle phase. Repeated exposure to a low dose of U50,488H (1 mg/kg/day s.c. for one month) provides sustained relief of mechanical hypersensitivity, without tolerance development or sedative side effects. Interestingly, this treatment also inhibits a decreased rearing behavior associated with spontaneous pain or discomfort in endometriosis mice. This KOR-mediated pain relief does not prevent the anxiety-like behavior or the cognitive impairment exhibited by endometriosis mice, and the growth of endometriotic cysts is also unaltered. These data provide evidence of strong pain-relieving properties of kappa opioid receptor stimulation in female mice with endometriosis pain. The persistence of affective and cognitive manifestations suggests that these comorbidities are independent of pelvic pain and simultaneous treatment of these comorbidities may be necessary for successful management of endometriosis.

Psychological Factors Are Associated with Pain at All Time Frames After Breast Cancer Surgery: A Systematic Review with Meta-Analyses

OBJECTIVE

This systematic review aimed to 1) assess associations between psychological factors and pain after breast cancer (BC) treatment and 2) determine which preoperative psychological factors predicted pain in the acute, subacute, and chronic time frames after BC surgery.

DESIGN

A systematic review with meta-analysis.

SUBJECTS

Women with early-stage BC.

METHODS

The Medline, EMBASE, CINAHL, and Web of Science databases were searched between 1990 and January 2019. Studies that evaluated psychological factors and pain after surgery for early-stage BC were included. Associations between psychological factors and pain, from early after surgery to >12 months after surgery, were extracted. Effect size correlations (r equivalents) were calculated and pooled by using random-effects meta-analysis models.

RESULTS

Of 4,137 studies, 47 were included (n = 15,987 participants; 26 studies ≤12 months after surgery and 22 studies >12 months after surgery). The majority of the studies had low to moderate risk of bias. Higher preoperative anxiety and depression were weak but significant predictors of pain at all time points up to 12 months (r equivalent: 0.15-0.22). Higher preoperative pain catastrophizing and distress were also weak but significant predictors of pain during the acute (0-7 days) and chronic (3-12 months) periods (r equivalent: 0.10-0.20). For the period >12 months after surgery, weak but significant cross-sectional associations with pain were identified for anxiety, depression, pain catastrophizing, and distress (r equivalents: 0.15, 0.17, 0.25, 0.14, respectively).

CONCLUSION

Significant pooled effect size correlations between psychological factors and pain were identified across all time frames. Though weak, these associations should encourage assessment of key psychological factors during preoperative screening and pain assessments at all postoperative time frames.

Prognostic factors for adolescent knee pain: an individual participant data meta-analysis of 1281 patients

ABSTRACT

Adolescent knee pain has a propensity for chronicity, impacting physical activity and health into adulthood. The aim of this study is to investigate prognostic factors in adolescents with knee pain using individual participant data (IPD) meta-analysis. Studies were identified through a systematic search and a collaborative group. We included IPD from prospective studies of adolescents (age 10-19 years) with nontraumatic knee pain (13 studies and 1516 adolescents with 1281 unique participants). Primary outcomes were pain intensity and function (Knee Injury and Osteoarthritis Outcome Score "Sport/Rec" subscale). Primary endpoint was 12 months. Risk of bias was appraised with Quality in Prognosis Studies tool. Harmonised IPD was analysed by multilevel modelling. Fifty-one percent reported knee pain after 12-months. Lower baseline pain frequency was associated with lower pain intensity at 12 months ("less than weekly"; 12 (95% confidence interval [CI] 7-17) and "monthly"; 15 (95% CI 9-22) points lower on a 100-point pain scale, compared with "almost daily pain"). Other factors most strongly associated with 1-year pain prognosis were lower quality of life (30, 95% CI 19-42 points per unit change in the EQ5D index score), female sex (8 points, 95% CI 4-12 higher compared with males), and bilateral pain (7, 95% CI 1-13 points higher pain). Similar factors were associated with function. Body mass index, pain sensitivity, and knee strength were not associated with prognosis of pain or function. Adolescent knee pain is associated with clinically relevant long-term pain and functional deficits. Self-reported characteristics may help identify those at risk of poor prognosis.

Good Sleep Quality Improves the Relationship Between Pain and Depression Among Individuals With Chronic Pain

Individuals with chronic pain often experience co-existing sleep problems and depression-related states. Chronic pain, sleep problems, and depression interrelate, and have been shown to exacerbate one another, which negatively impacts quality of life. This study explored the relationships between pain severity, pain interference, sleep quality, and depression among individuals with chronic pain. Secondly, we tested whether sleep quality may moderate the relationship between pain and depression. A cross-sectional survey was completed by 1,059 adults with non-malignant chronic pain conditions (M age 43 years, 88% identified as women) and collected measures related to pain severity, pain interference, sleep quality, and depression. Multiple regression analyses found that pain severity, pain interference, and sleep quality are all significantly associated with depression. Secondly, moderated regression analyses revealed that sleep quality moderates the relationship between pain interference and depression among individuals with chronic pain such that good sleep quality attenuates the effect of pain interference on depression, and poor sleep quality amplifies the effect of pain interference on depression. These findings suggest that sleep quality may be a relevant therapeutic target for individuals with chronic pain and co-existing depression.

Sleep Well and Recover Faster with Less Pain-A Narrative Review on Sleep in the Perioperative Period

Sleep disturbance, pain, and having a surgical procedure of some kind are all very likely to occur during the average lifespan. Postoperative pain continues to be a prevalent problem and growing evidence supports the association between pain and sleep disturbances. The bidirectional nature of sleep and pain is widely acknowledged. A decline in sleep quality adds a risk for the onset of pain and also exacerbates existing pain. The risk factors for developing insomnia and experiencing severe pain after surgery are quite similar. The main aim of this narrative review is to discuss why it is important to be aware of sleep disturbances both before and after surgery, to know how sleep disturbances should be assessed and monitored, and to understand how better sleep can be supported by both pharmacological and non-pharmacological interventions.

Effects of chronic pain on sleep quality and depression: A cross-sectional study

Objectives:

To examined the impacts of chronic pain on depression and poor sleep quality dimensions as well as the mediating function of poor sleep quality in the pathway between chronic pain and depression.

Methods:

Between March 2019 and February 2020, we conducted a cross-sectional study on 233 chronic pain patients in 2 tertiary hospitals in Riyadh, Saudi Arabia.

Results:

Of the 233 patients, 36% had depression, while 66.1% had poor sleep quality. Chronic pain intensity and pain disability significantly explained 10.9% of depressed affect variance, 4.9% of anhedonia variance, 17.3% of somatic complaint variance, 4.5% of interpersonal difficulty variance, 7.4% of sleep efficiency variance, and 15% of perceived sleep quality variance. The result also showed a positive, direct effect of chronic pain on poor sleep quality, which in turn positively and directly affect depression. However, chronic pain had only indirect effect on depression.

Conclusions:

Among chronic pain patients, the high rates of poor sleep quality and depression requires a special attention. Chronic pain intensity and disability predict depression and sleep quality dimensions differently. The result underlines the need of managing poor sleep quality to address depression in the context of chronic pain.

The Impact of Guided Imagery on Pain and Anxiety in Hospitalized Adults

BACKGROUND

The use and impact of guided imagery in the acute care setting is limited.

AIMS

The purpose of this quality improvement project was to evaluate the feasibility of a guided imagery intervention to change pain scores, anxiety scores, and opioid analgesia usage among hospitalized adults in an acute care setting.

DESIGN

Quality improvement project using three measurements (baseline, 24 hours, and 48 hours).

SETTINGS

Acute care hospital.

PARTICIPANTS/SUBJECTS

Adult inpatients referred to an APRN-led pain management service.

METHODS

The intervention was the use of a 30-minute guided imagery recording delivered via MP3 player which patients used twice daily.

RESULTS

Limited changes were seen in pain scores, with no statistically significant results (p = .449). Statistically significant reductions were found in both anxiety scores (p < .001) and opioid analgesia usage (p = .043).

CONCLUSIONS

Findings from this quality improvement project support the impact of guided imagery on anxiety and opioid analgesia use. Changes in pain scores were not demonstrated in this project. Additional research with a rigorous design is needed to determine cause and effect conclusions.

CLINICAL IMPLICATIONS

The use of guided imagery as an adjunctive intervention for pain control may engage and empower the patient in self-care activities, which may have an impact on how care is perceived. Guided imagery is a low-cost, easily implemented approach that can be incorporated into patient care to reduce anxiety and, potentially, opioid analgesia use.

The Role of Sleep in the Transition from Acute to Chronic Musculoskeletal Pain in Youth-A Narrative Review

Musculoskeletal pain is common in the general pediatric population and is a challenge to youth, their parents, and society. The majority of children experiencing musculoskeletal pain will recover; however, a small subgroup of youth develops chronic pain. There is limited understanding of the factors that affect the transition from acute to chronic pain in youth. This review introduces sleep deficiency in the acute to chronic pain transition, exploring the potential mediational or mechanistic role and pathways of sleep in this process, including the interaction with sensory, psychological, and social components of pain and highlighting new avenues for treatment. Biological mechanisms include the increased production of inflammatory mediators and the effect on the hypothalamus-pituitary-adrenal (HPA) axis and on the dopaminergic signaling. Psychological and social components include the effect of sleep on the emotional-affective and behavioral components of pain, the negative impact on daily and social activities and coping strategies and on the reward system, increased pain catastrophizing, fear of pain, pain-related anxiety, hypervigilance, and social isolation. Future longitudinal studies are needed to elucidate these mechanistic pathways of the effect of sleep on the transition from acute to chronic pain, which may lead to the development of new treatment targets to prevent this transition.

Temporomandibular disorder severity and diagnostic groups: Their associations with sleep quality and impairments

OBJECTIVES

This study evaluated the impact of TMD severity on sleep quality and established the associations between TMD diagnostic groups/pain subtypes and sleep impairments.

METHODS

A total of 1151 patients from a tertiary Dental Hospital were screened for eligibility. Consenting subjects who met the inclusion criteria were directed to complete a general/health questionnaire, the Fonseca Anamnestic Index (FAI), Diagnostic Criteria for Temporomandibular disorders (DC/TMD) Symptom Questionnaire, and Pittsburgh Sleep Quality Index (PSQI) at their intake visit. Patients who screened positive for TMDs with the FAI were subjected to a protocolized physical examination and TMD diagnostic groups/subtypes were subsequently derived based on the DC/TMD "diagnostic tree" and algorithms. Statistical analyses were conducted using non-parametric methods and logistic regression (α = 0.05).

RESULTS

The final sample consisted of 845 subjects with TMDs and 116 TMD-free controls. The mean age of the TMD and TMD-free subjects were 33.17 ± 13.55 and 31.66 ± 9.50 years. Subjects with severe and moderate TMDs had significantly greater global PSQI scores than those with mild and no TMDs (p < 0.001). Those with pain-related, intra-articular, and combined TMDs reported significantly poorer sleep quality than those with no TMDs (p < 0.001). Moreover, subjects with myalgia and myalgia plus arthralgia presented significantly greater sleep impairments than their counterparts with intra-articular disorders (p < 0.001). Multivariate logistic regression indicated that pain-related (OR = 3.23; CI = 1.69-6.14) and intra-articular TMDs (OR = 1.91; CI = 1.15-3.16) were most related to poor sleep.

CONCLUSIONS

Sleep quality worsened with increasing TMD severity and the presence of painful and intra-articular TMDs increased the likelihood of poor sleep.

Association Between Pretreatment Sleep Disturbance and Radiation Therapy-Induced Pain in 573 Women With Breast Cancer

CONTEXT

Pain can be a debilitating side effect of radiation therapy (RT). Data from the general population have shown that sleep disturbance can influence pain incidence and severity; however, less is known about this relationship in patients with breast cancer receiving RT.

OBJECTIVES

This secondary analysis examined the association of pretreatment moderate/severe levels of sleep disturbance with subsequent RT-induced pain after adjusting for pre-RT pain.

METHODS

We report on 573 female patients with breast cancer undergoing RT from a previously completed Phase II clinical trial for radiation dermatitis. Sleep disturbance, total pain, and pain subdomains-sensory pain, affective pain, and perceived pain intensity were assessed at pre-RT and post-RT. At pre-RT, patients were dichotomized into two groups: those with moderate/severe sleep disturbance (N = 85) vs. those with no/mild sleep disturbance (control; N = 488).

RESULTS

At pre-RT, women with moderate/severe sleep disturbance were younger, less likely to be married, more likely to have had mastectomy and chemotherapy, and more likely to have depression/anxiety disorder and fatigue than the control group (all Ps < 0.05). Generalized estimating equations model, after controlling for pre-RT pain and other covariates (e.g., trial treatment condition and covariates that were significantly correlated with post-RT pain), showed that women with moderate/severe sleep disturbance at pre-RT vs. control group had significantly higher mean post-RT total pain as well as sensory, affective, and perceived pain (effect size = 0.62, 0.60, 0.69, and 0.52, respectively; all Ps < 0.05).

CONCLUSION

These findings suggest that moderate/severe disturbed sleep before RT is associated with increased pain from pre-to-post-RT in patients with breast cancer.

Positive Encounters as a Buffer: Pain and Sleep Disturbances in Older Adults' Everyday Lives

Objectives: To test whether older adults' pain was bidirectionally associated with nighttime sleep disturbances and whether daily positive encounters attenuated these associations. Methods: Participants (N = 292, mean = 73.71 years old) from the Daily Experiences and Well-being Study indicated pain and positive encounters with close partners (e.g., family and friends) and nonclose partners (e.g., acquaintances and service providers) every 3 hours throughout each day across 4-6 days. They also reported nighttime sleep disturbances the following morning. Results: Multilevel models revealed that participants with more prior nighttime sleep disturbances reported more severe pain the next day. This link was attenuated on days when participants had a greater proportion of positive encounters or viewed encounters as more pleasant, especially when these encounters occurred with close partners. Discussion: This study identifies benefits of positive encounters to older adults and sheds light on ways that may alleviate their pain from a social perspective.

Are psychological symptoms a risk factor for musculoskeletal pain in adolescents?

Adolescent musculoskeletal pain is common and is associated with musculoskeletal pain in adulthood. Psychological symptoms, also common in adolescence, have been shown to be associated with musculoskeletal pain, but the current evidence is mixed and may be dependent on effect modifiers. This study investigated whether adolescents with psychological symptoms (internalizing and externalizing constructs) at age 13 years were at higher odds for musculoskeletal pain at age 17 years and whether the associations were modified by pubertal status and sex. A prospective cohort design examined data on 3865 adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC). Associations between baseline (aged 13 years) internalizing and externalizing symptoms and musculoskeletal pain at follow-up (aged 17 years) were investigated using logistic regression producing odds ratios (OR) and 95% confidence intervals (95% CI). In total 43.1% of adolescents reported musculoskeletal pain at follow-up. Externalizing symptoms at baseline increased the odds of musculoskeletal pain (OR 1.68, 95% CI 1.28, 2.20), and internalizing symptoms demonstrated a non-significant increase (OR 1.26, 95% CI 0.98, 1.62). Effect modification analysis showed an increased effect dependent on pubertal status.Conclusion: Adolescents with externalizing symptoms, and to some extent internalizing symptoms, are at increased odds of later musculoskeletal pain. Future research is now required to understand the reasons for these associations. What is Known: • Current evidence regarding the association between internalizing symptoms and externalizing symptoms and future musculoskeletal pain in adolescents is mixed. What is New: • This study found that adolescents with externalizing symptoms, and to some extent internalizing symptoms, are at increased odds for musculoskeletal pain, with an increased influence dependent on pubertal status. • These results are of interest for the development of timely preventative interventions designed to reduce the risk of musculoskeletal pain.

Structural and functional brain abnormalities in postherpetic neuralgia: A systematic review of neuroimaging studies

In recent decades, an increasing number of neuroimaging studies utilizing magnetic resonance imaging (MRI) have explored the differential effects of postherpetic neuralgia (PHN) on brain structure and function. We systematically reviewed and integrated the findings from relevant neuroimaging studies in PHN patients. A total of 15 studies with 16 datasets were ultimately included in the present study, which were categorized by the different neuroimaging modalities. The results revealed that PHN was closely associated with structural/microstructural and functional abnormalities of the brain mainly located in the 'pain matrix', including the thalamus, insula, parahippocampus, amygdala, dorsolateral prefrontal cortex, precentral gyrus and inferior parietal lobe, as well as other regions, such as the precuneus, lentiform nucleus and brainstem. Furthermore, a disruption of multiple networks, including the default-mode network, salience network and limbic system, may contribute to the neurophysiological mechanisms underlying PHN. The findings indicate that the cerebral abnormalities of PHN were not restricted to the pain matrix but extended to other regions, profoundly affecting the regulation and moderation of pain processing in PHN. Future prospective and longitudinal neuroimaging studies with larger samples will elucidate the progressive trajectory of neural changes in the pathophysiological process of PHN.

Working nights and lower leisure-time physical activity associate with chronic pain in Southern African long-distance truck drivers: A cross-sectional study

Background

In South Africa, the trucking industry employs over 70,000 people and the prevalence of chronic pain in this occupational group was reported at 10%. We investigated factors associated with chronic pain in truck drivers including mental health, physical activity, and sleep, as no study has done so.

Methods

Southern African male, long-distance truck drivers were recruited at truck stops in Gauteng and Free State Provinces, South Africa (n = 614). Chronic pain was defined as pain present for at least the last three months. Depressive symptoms were assessed with the Patient Health Questionnaire-9, post-traumatic stress disorder with the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5), exposure to traumatic events with the Life Events Checklist-5 (LEC-5) and daytime sleepiness with the Epworth Sleepiness Scale. Sleep quality was measured on a four-point Likert scale. Leisure-time physical activity was measured using the Godin-Shephard leisure-time physical activity questionnaire. Associations between these factors, demographic factors and chronic pain were investigated.

Results

Multivariate analysis showed that working ≥ 2 nights/week (OR = 2.68, 95% CI = 1.55–4.68) was associated with chronic pain and physical activity was protective (OR = 0.97, 95% CI 0.95–0.98). In an exploratory analysis, greater depressive symptoms (p = 0.004), daytime sleepiness (p = 0.01) and worse sleep quality (p = 0.001) was associated with working ≥ 2 nights/week. Lower leisure-time physical activity was associated with worse sleep quality (p = 0.006), but not daytime sleepiness or depressive symptoms (p>0.05).

Conclusions

There is a clear relationship between working nights and activity levels, and chronic pain, sleep quality, and depression in truck drivers.

Disentangling comorbidity in chronic pain: A study in primary health care settings from India

OBJECTIVES

The study examined the prevalence, sociodemographic, and clinical correlates of chronic pain among primary care patients in the state of Kerala, India. It also examined the patterns and relationships of chronic physical and mental health conditions with chronic pain.

METHODS

This study is a cross-sectional survey conducted among 7165 adult patients selected randomly by a multi-stage stratified design from 71 primary health centers. The questionnaires administered included Chronic pain screening questionnaire, self-reported Chronic physical health condition checklist, Patient Health Questionnaire-SADS, The Alcohol Use Disorders Identification Test, Fagerström Test for Nicotine Dependence, WHO Disability Assessment Schedule and WHOQOL- BREF for Quality/Satisfaction with Life. The prevalence and comorbid patterns of chronic pain were determined. Logistic regression analysis and generalized linear mixed-effects model was employed to examine the relationship of chronic pain to socio-demographic variables and examined physical and mental health conditions.

RESULTS

A total of 1831 (27%) patients reported chronic pain. Among those with chronic pain, 28.3% reported no co-occurring chronic mental or physical illness, 35.3% reported one, and 36.3% reported multi-morbidity. In the multivariate analysis, patients with chronic pain when compared to those without had higher odds of being older, female, having lower education, not living with their family, greater disability, and poor satisfaction with life. Chronic pain was independently associated with both medical (hypertension, diabetes mellitus, tuberculosis, arthritis, and other medical illnesses) and mental health conditions (depressive disorders, anxiety disorders, and tobacco dependence). It showed a varying strength of association and additive effect with increasing number of co-occurring physical and mental illnesses.

CONCLUSIONS

Chronic pain is a common condition among primary care attendees associated with significant burden of medical and mental health comorbidity. The findings highlight the need to incorporate treatment models that will ensure appropriate management to improve outcomes within the resource constraints.

Medical cannabis and insomnia in older adults with chronic pain: a cross-sectional study

OBJECTIVES

Medical cannabis (MC) is increasingly being used for treatment of chronic pain symptoms. Among patients there is also a growing preference for the use of MC to manage sleep problems. The aim of the current study was to examine the associations between use of whole plant cannabis and sleep problems among chronic pain patients.

METHODS

A total of 128 individuals with chronic pain over the age of 50 years were recruited from the Rambam Institute for Pain Medicine in Haifa, Israel. Of them, 66 were MC users and 62 were non-users. Regression models tested the differences in sleep problems between the two groups. Furthermore, Pearson correlations between MC use measures (dose, length and frequency of use, number of strains used, tetrahydrocannabinol/cannabidiol levels) and sleep problems were assessed among MC users.

RESULTS

After adjustment for age, sex, pain level and use of sleep and anti-depressant medications, MC use was associated with less problems with waking up at night compared with non-MC use. No group differences were found for problems with falling asleep or waking up early without managing to fall back asleep. Frequent MC use was associated with more problems waking up at night and falling asleep.

CONCLUSIONS

MC use may have an overall positive effect on maintaining sleep throughout the night in chronic pain patients. At the same time, tolerance towards potential sleep-inducing properties of MC may occur with frequent use. More research based on randomised control trials and other longitudinal designs is warranted.

The Potential Contribution of Chronic Pain and Common Chronic Pain Conditions to Subsequent Cognitive Decline, New Onset Cognitive Impairment, and Incident Dementia: A Systematic Review and Conceptual Model for Future Research

BACKGROUND

Growing evidence suggests that chronic pain and certain chronic pain conditions may increase risk for cognitive decline and dementia.

OBJECTIVE

In this systematic review, we critically evaluate available evidence regarding the association of chronic pain and specific common chronic pain conditions to subsequent decline in cognitive function, new onset cognitive impairment (CI), and incident Alzheimer's disease and related dementias (ADRD); outline major gaps in the literature; and provide a preliminary conceptual model illustrating potential pathways linking pain to cognitive change.

METHODS

To identify qualifying studies, we searched seven scientific databases and scanned bibliographies of identified articles and relevant review papers. Sixteen studies met our inclusion criteria (2 matched case-control, 10 retrospective cohort, 2 prospective cohort), including 11 regarding the association of osteoarthritis (N = 4), fibromyalgia (N = 1), or headache/migraine (N = 6) to incident ADRD (N = 10) and/or its subtypes (N = 6), and 5 investigating the relation of chronic pain symptoms to subsequent cognitive decline (N = 2), CI (N = 1), and/or ADRD (N = 3).

RESULTS

Studies yielded consistent evidence for a positive association of osteoarthritis and migraines/headaches to incident ADRD; however, findings regarding dementia subtypes were mixed. Emerging evidence also suggests chronic pain symptoms may accelerate cognitive decline and increase risk for memory impairment and ADRD, although findings and measures varied considerably across studies.

CONCLUSION

While existing studies support a link between chronic pain and ADRD risk, conclusions are limited by substantial study heterogeneity, limited investigation of certain pain conditions, and methodological and other concerns characterizing most investigations to date. Additional rigorous, long-term prospective studies are needed to elucidate the effects of chronic pain and specific chronic pain conditions on cognitive decline and conversion to ADRD, and to clarify the influence of potential confounding and mediating factors.

Sleep Characteristics in Diabetic Patients Depending on the Occurrence of Neuropathic Pain and Related Factors

This study aims to compare the sleep characteristics (structure and quality) in patients with type-2 diabetes mellitus with and without diabetic neuropathic pain (DNP), and to investigate the relationship of sensory phenotypes, anxiety, and depression with sleep quality in DNP patients. A cross-sectional study was performed in patients with type-2 diabetes mellitus and neuropathy. Patients were classified into two groups—with or without neuropathic pain—according to the “Douleur Neuropathique-4 (DN4)” scale. Sleep characteristics and quality (Medical Outcomes Study—MOS-sleep), pain phenotype (Neuropathic Pain Symptom Inventory—NPSI), mood status (Hospital Anxiety and Depression scale—HADS), pain intensity (Visual Analogue Scale—VAS), and quality of life (SF-12v2) were measured. The sample included 130 patients (65 with DNP). The mean scores in all the dimensions of the MOS-sleep scale were higher (more disturbances) in the DNP patients. Higher scores in anxiety or depression, greater intensity of pain or a higher score in the paroxysmal pain phenotype were associated with lower sleep quality in DNP patients. A shorter duration of the diabetes and lower levels of glycated hemoglobin were also associated with lower sleep quality. The results show the relationship between DNP and sleep quality, and the importance of assessing sensory phenotypes and mental comorbidities in these patients. Taking these factors into consideration, to adopt a multimodal approach is necessary to achieve better clinical results.

Effect of Psychological Inflexibility on Depressive Symptoms and Sleep Disturbance among Japanese Young Women with Chronic Pain

Background: Psychological inflexibility based on an acceptance and commitment therapy model is theoretically well-established as a process to exacerbate psychological distress, such as depressive symptoms and sleep disturbance. This study aimed to examine the associations of psychological inflexibility with depressive symptoms and sleep distribution. We hypothesized that psychological inflexibility would be associated with higher levels of depressive symptoms and sleep disturbance in women with chronic pain. Methods: Female college students in Japan answered a questionnaire on pain status, treatment, and psychological inflexibility as measured by the Acceptance and Action Questionnaire-Ⅱ before answering questionnaires on depressive symptoms and sleep disturbance eight months after. Results: Women with chronic pain (n = 320) reported more severe depressive symptoms and sleep disturbances compared to women without chronic pain (n = 90). Hierarchical multiple regressions revealed that psychological inflexibility predicted higher levels of depressive symptoms and sleep disturbance, independent of the pain intensity, whether they consulted a doctor or used pain medication. Conclusion: Based on our findings self-management interventions aimed at reducing psychological inflexibility should be developed for individuals who are experiencing chronic pain.

The effect of mindful attention training for pain modulation capacity: Exploring the mindfulness-pain link

OBJECTIVE

Mindfulness has been shown to be beneficial for chronic pain. The underlying mechanisms of the mindfulness-pain link, however, are yet to be established. Particularly, the effects of mindfulness on pain modulation, which is shown to be dysfunctional among chronic pain patients, barely has been tested. This study investigated whether a short mindful attention training based on Langerian mindfulness mitigates reductions in pain modulation.

METHOD

Systemic quantitative-somatosensory testing of conditioned pain modulation (CPM) was conducted in 60 undergraduates, who were randomly assigned to one of three groups: (1) Pain-specific mindful attention training; (2) nonspecific mindful attention training; and (3) no mindful attention training. CPM was tested before and after the intervention.

RESULTS

As hypothesized, a reduction in CPM magnitude was observed only in the control group, whereas this reduction was abolished in the two mindfulness groups.

CONCLUSIONS

Langerian mindfulness may mitigate pain modulation reduction as observed in chronic pain, thus shedding light on its potential advantages.

Tumor-Induced Osteomalacia and the Importance of Plasma Fibroblast Growth Factor 23 as an Indicator: Diagnostic Delay Leads to a Suicide Attempt

Tumor-induced osteomalacia is a rare hypophosphatemic disease caused by unregulated production of fibroblast growth factor 23 by a tumor, thereby inducing renal phosphate wasting and inhibiting appropriate increase of calcitriol production. Symptoms of tumor-induced osteomalacia, including muscle weakness, bone pain, and pathologic fractures, are nonspecific and warrant further workup. We report the case of a 50-year-old African American female with no known psychiatric illness who was admitted after a failed suicide attempt provoked by severe bone pain. She had been treated for fibromyalgia and hypophosphatemic rickets at other facilities with no improvement. The findings of profound renal phosphate wasting initiated further evaluation, which revealed an elevated fibroblast growth factor 23 level and a right proximal fibular mesenchymal tumor on octreotide scintigraphy. Magnetic resonance imaging confirmed the findings of a solid intramuscular tumor corresponding to the octreotide avid lesion. After wide excision of the tumor, serum phosphate and parathyroid hormone levels began to normalize. This case highlights the importance of extensively investigating the cause of bone pain, weakness, and fatigue in patients without a family history of hypophosphatemia or bone disorders. The aforementioned symptoms may precede recurrent pathological fractures, and a thorough workup ensures that a diagnosis of tumor is not delayed or overlooked, as tumor resection confers a favorable prognosis and dramatic increase in the quality of life for patients.

Relationship between diabetic neuropathic pain and comorbidity. Their impact on pain intensity, diabetes complications and quality of life in patients with type-2 diabetes mellitus

OBJECTIVE

To compare cognitive function, mood and sleep status in patients with and without diabetic neuropathic pain (DNP) and their relationship with pain intensity, diabetes complications, and quality of life. To determine whether these relationships differ depending on the sensorial phenotype.

METHODS

Cross-sectional study performed on patients with type-2 diabetes-mellitus and neuropathy. Presence of DNP, pain intensity and phenotype, mood status, sleep characteristics and quality of life were measured.

RESULTS

A total of 130 patients (65 with DNP) were included. DNP was related to poor sleep quality (OR = 1.03;CI95%:1.02-1.05), pain treatment (OR = 3.00,CI95%:1.24-7.29) or previous anxiety (OR = 2.70,CI95%:1.05-6.99). Patients with specific phenotypes or depression (=0.82,CI95%:-0.02-1.67) referred more severe pain. More complications were related to older age (OR = 1.40,CI95%:1.12-1.66), higher pain intensity (OR = 1.51,CI95%:1.00-2.28), lower cognitive performance (OR = 1.25,CI95%:1.09-1.43), previous anxiety (OR = 10.48,CI95%:1.46-75.24) and insulin treatment (OR = 124.50,CI95%:6.64-2335.06). Decrease in mental quality of life was associated with sleep disorders (β = -0.33,CI95%:-0.48,-0.23), physical comorbidities (β = -9.73,CI95%:-18.15, -1.31) and previous anxiety (β = -7.91,CI95%:-13.04, -2.77). Lower scores in physical quality of life were related to sleep disorders (β = -0.12,CI95%:-0.21, -0.18), obesity (β = -8.35,CI95%:-13.16, -3.55), longer time since diagnosis (β = -0.72,CI95%:-1.44;0.01) and disability (β = -14.58,CI95%:-24.69; -4.48).

CONCLUSIONS

The results support the idea that mental comorbidity and sleep disorders are factors associated with DNP and greater pain intensity, more diabetes complications and lower quality of life. Moreover, they highlight the relationship between sensorial phenotypes and pain intensity, and lower cognitive performance and diabetes complications.

Effects of repeated treatment with monoamine-transporter-inhibitor antidepressants on pain-related depression of intracranial self-stimulation in rats

RATIONALE

Synaptic neurotransmission with dopamine (DA), norepinephrine (NE), and serotonin (5-HT) is terminated primarily by reuptake into presynaptic terminals via the DA, NE, and 5-HT transporters (DAT/NET/SERT, respectively). Monoamine transporter inhibitors constitute one class of drugs used to treat both depression and pain, and therapeutic effects by these compounds often require repeated treatment for days or weeks.

OBJECTIVES

The present study compared antinociceptive effects produced by repeated treatment with monoamine transporter inhibitors in a preclinical assay of pain-related depression of positively reinforced operant responding.

METHODS

Adult Sprague-Dawley rats equipped with microelectrodes targeting a brain-reward area responded for pulses of electrical brain stimulation in an intracranial self-stimulation (ICSS) procedure. Intraperitoneal injection of dilute lactic acid served as a noxious stimulus that repeatedly depressed ICSS and also produced weight loss during 7 days of repeated acid administration.

RESULTS

Acid-induced depression of both ICSS and body weight were completely blocked by repeated pretreatment with the nonsteroidal anti-inflammatory drug ketorolac. The DAT-selective inhibitor bupropion also fully blocked acid-induced ICSS depression and weight loss throughout all 7 days of treatment. The NET-selective inhibitor nortriptyline and the SERT-selective inhibitor citalopram were generally less effective, but both drugs blocked acid-induced ICSS depression by the end of the 7-day treatment. Acid-induced depression of ICSS and body weight were not blocked by the kappa opioid receptor (KOR) agonist U69593 or the KOR antagonist norbinaltorphimine.

CONCLUSIONS

These results support effectiveness of bupropion to alleviate signs of pain-related behavioral depression in rats and further suggest that nortriptyline and citalopram produce significant but less reliable effects.