Reciprocal interaction between depression and pain: results from a comprehensive bidirectional Mendelian randomization study and functional annotation analysis

Functional Brain Changes in Younger Population of Cervical Spondylosis Patients with Chronic Neck Pain

Purpose

The aim of the research was to observe the variations in brain activity between young cervical spondylosis patients with chronic neck pain (CNP) and healthy volunteers in the resting state and to investigate the central remodeling mechanisms in the patients.

Patients and methods

Our study recruited 31 patients with chronic neck pain from cervical spondylosis and 30 healthy volunteers. Eventually, 29 patients (CNP group) and 29 healthy volunteers (HC group) completed the acquisition of clinical data and resting-state functional magnetic resonance (rs BOLD-fMRI) amplitude of low-frequency fluctuations (ALFF) data; in addition, we assessed the relationship between differentially active brain regions and clinical indicators.

Results

The CNP group found greater ALFF values in the insula, cingulate gyrus, prefrontal lobe, and other brain regions. The occipital, parietal, and other brain regions had lower ALFF values. In addition, there was a negative connection between the duration of the sickness in the CNP group and the ALFF value of the right superior parietal gyrus (SPG.R). The level of tenderness threshold exhibited a negative correlation with the ALFF value of the left insula (INS.L). In addition, the NPQ score showed a negative association with the ALFF value of the ORBinf.R and a positive correlation with the ALFF value of the CC1.L. Finally, the HADS-A score exhibited a positive correlation with the ALFF value of the right anterior cingulate and paracingulate gyrus (ACG.R).

Conclusion

Young patients with chronic neck pain show extensive central remodeling, with altered functional activity in pain-emotion brain areas (such as the cingulate gyrus and insula), pain-cognition brain areas (such as the prefrontal lobe), and other special sensory brain areas (such as the parietal and occipital lobes). These changes are linked to clinical tenderness, functional disability, and negative emotion indicators.

The association among multiple-site chronic pain, sedentary behavior, and major depressive disorders: a mendelian randomization study

OBJECTIVE

Observational studies have reported that major depressive disorder (MDD) is associated with sedentary behavior (SB) and multiple chronic pain (MCP), but their associations remain unclear. Mendelian randomization analysis was used to assess the association.

METHODS

Single nucleotide polymorphisms (SNPs) associated with MCP, SB [time spent watching television (Tel), using a computer (Com), or driving (Dri)], and MDD were collected from genome-wide association studies and screened as instrumental variants with a threshold of 1 × 10 -5 . Mendelian randomization was performed to examine their associations. Sensitivity analyses were conducted to evaluate robustness.

RESULTS

MCP was associated with a higher risk of MDD [odds ratio (OR) inverse variance weighting (IVW)  = 1.88; 95% confidence interval (CI), 1.64-2.15; P  = 4.26 × 10 -8 ), and causally related to SB (Tel: OR IVW  = 1.23; 95% CI, 1.19-1.26; P  = 6.02 × 10 -38 ) (Dri: OR IVW  = 1.05; 95% CI, 1.03-1.08; P  = 3.92 × 10 -5 ). Causality of SB on MCP was detected for Tel (OR IVW  = 1.46; 95% CI, 1.39-1.53; P  = 1.40 × 10 -54 ) and Com (OR IVW  = 0.88; 95% CI, 0.83-0.93; P  = 2.50 × 10 -6 ). No association was observed for SB on MDD. There is currently insufficient evidence to support that leisure activities are a mediating factor in MCP-induced MDD.

CONCLUSION

There are complex relationships among MCP, SB, and MDD. More research and learning about potential relationships and mechanisms among these phenotypes should be supplied.

Advances and challenges in neuroimaging-based pain biomarkers

Identifying neural biomarkers of pain has long been a central theme in pain neuroscience. Here, we review the state-of-the-art candidates for neural biomarkers of acute and chronic pain. We classify these potential neural biomarkers into five categories based on the nature of their target variables, including neural biomarkers of (1) within-individual perception, (2) between-individual sensitivity, and (3) discriminability for acute pain, as well as (4) assessment and (5) prospective neural biomarkers for chronic pain. For each category, we provide a synthesized review of candidate biomarkers developed using neuroimaging techniques including functional magnetic resonance imaging (fMRI), structural magnetic resonance imaging (sMRI), and electroencephalography (EEG). We also discuss the conceptual and practical challenges in developing neural biomarkers of pain. Addressing these challenges, optimal biomarkers of pain can be developed to deepen our understanding of how the brain represents pain and ultimately help alleviate patients' suffering and improve their well-being.

The causal relationship between major depression disorder and thyroid diseases: A Mendelian randomization study and mediation analysis

BACKGROUND

Studies have been conducted on the relationship between depression and thyroid diseases and function, its causal relationship remains unclear.

METHODS

Using summary statistics of genome-wide association studies of European and East Asian ancestry, we conducted 2-sample bidirectional Mendelian randomization to estimate the association between MDD and thyroid function (European: normal range TSH, T4, T3, fT4, TPOAb levels and TPOAb-positives; East Asian: T4) and thyroid diseases (hypothyroidism, hyperthyroidism, and Hashimoto's thyroiditis), and used Mediation analysis to evaluate potential mediators (alcohol intake, antidepressant) of the association and calculate the mediated proportions.

RESULTS

It was observed a significant causal association between MDD on hypothyroidism (P = 8.94 × 10-5), hyperthyroidism (P = 8.68 × 10-3), and hashimoto's thyroiditis (P = 3.97 × 10-5) among European ancestry, which was mediated by Alcohol intake (alcohol intake versus 10 years previously for hypothyroidism (P = 0.026), hashimoto's thyroiditis (P = 0.042), and alcohol intake frequency for hypothyroidism (P = 0.015)) and antidepressant (for hypothyroidism (P = 0.008), hashimoto's thyroiditis (P = 0.010)), but not among East Asian ancestry (PMDD-hypothyroidism = 0.016, but β direction was different; PMDD-hyperthyroidism = 0.438; PMDD-hashimoto's thyroiditis = 0.496). There was no evidence for bidirectional causal association between thyroid function mentioned above and MDD among both ancestry (all P > 0.05).

CONCLUSION

We importantly observed a significant causal association between MDD on risk of hypothyroidism, hyperthyroidism, and hashimoto's thyroiditis among European ancestry, and Alcohol intake and antidepressant as mediators for prevention of hypothyroidism, hashimoto's thyroiditis attributable to MDD.

Associations between lifestyle-related risk factors and back pain: a systematic review and meta-analysis of Mendelian randomization studies

BACKGROUND

Mendelian randomization (MR) studies have an advantage over conventional observational studies when studying the causal effect of lifestyle-related risk factors on back pain. However, given the heterogeneous design of existing MR studies on back pain, the reported causal estimates of these effects remain equivocal, thus obscuring the true extent of the biological effects of back pain lifestyle-risk factors.

PURPOSE

The purpose of this study was to conduct a systematic review with multiple meta-analyses on the associations between various lifestyle factors and low back pain.

METHODS

We conducted a PRISMA systematic review and specifically included MR studies to investigate the associations between lifestyle factors-specifically, BMI, insomnia, smoking, alcohol consumption, and leisure sedentary behavior-and various back pain outcomes. Each meta-analysis synthesized data from three or more studies to assess the causal impact of these exposures on distinct back pain outcomes, including chronic pain, disability, and pain severity. Quality of studies was assessed according to STROBE-MR guidelines.

RESULTS

A total of 1576 studies were evaluated and 20 were included. Overall, the studies included were of high quality and had a low risk of bias. Our meta-analysis demonstrates the positive causal effect of BMI (OR IVW-random effects models: 1.18 [1.08-1.30]), insomnia(OR IVW-random effects models: 1.38 [1.10-1.74]), smoking(OR IVW-fixed effects models: 1.30 [1.23-1.36]), alcohol consumption(OR IVW-fixed effects models: 1.31 [1.21-1.42]) and leisure sedentary behaviors(OR IVW-random effects models: 1.52 [1.02-2.25]) on back pain.

CONCLUSION

In light of the disparate designs and causal effect estimates presented in numerous MR studies, our meta-analysis establishes a compelling argument that lifestyle-related risk factors such as BMI, insomnia, smoking, alcohol consumption, and leisure sedentary behaviors genuinely contribute to the biological development of back pain.

Bidirectional relationship between chronic pain and depressive symptoms in middle-aged and older adults

OBJECTIVE

To assess the bidirectional association between chronic pain and depressive symptoms among middle-aged and older adults from two prospective cohort studies.

METHODS

We used prospective data (12y of follow-up) from the English Longitudinal Study of Ageing (n = 9149, 5018 women, 65.0 ± 10.2y) and the Health and Retirement Study (n = 16,883, 9810 women, 66.9 ± 10.3y), including data from seven waves of each cohort between 2006 and 2018/2019. Depressive symptoms were assessed using the Centre of Epidemiological Studies Depression scale, while chronic pain was estimated using questions about the frequency of being troubled with pain. We used random-intercept cross-lagged panel models to assess the bidirectional association between pain and depressive symptoms, adjusting for potential confounders.

RESULTS

There was a cross-lagged effect of chronic pain on depressive symptoms (ELSA: β: 0.038; 95%CI: 0.011-0.066. Standardized coefficient (B): 0.021.

SHARE

β: 0.044; 95%CI: 0.023-0.065. B: 0.023-0.024) as well as depressive symptoms on pain (ELSA: β: 0.010; 95%CI: 0.002-0.018. B: 0.017-0.019.

SHARE

0.011; 95%CI: 0.005-0.017. B: 0.020-0.021). Moreover, there were auto-regressive effects of both chronic pain (ELSA: β: 0.149; 95%CI: 0.128-0.171.

SHARE

β: 0.129; 95%CI: 0.112-0.145) and depressive symptoms (ELSA: β: 0.149; 95%CI: 0.130-0.168.

SHARE

β: 0.169; 95%CI: 0.154-0.184).

CONCLUSION

We identified a modest bidirectional association between depressive symptoms and chronic pain, using two large prospective ageing cohorts.

Mendelian randomization highlights sleep disturbances mediated the effect of depression on chronic pain

INTRODUCTION

Depression and chronic pain are significant contributors to the global burden of disease. Previous research has revealed complex relationships between these two conditions, which may be influenced by sleep quality. However, observational studies have limitations, including confounding factors and reverse causation. This study aims to explore the mediating effects of sleep on the relationship between depression and chronic pain using Mendelian randomization (MR).

METHODS

We conducted a two-step, two-sample MR study using mediation analysis. We obtained major depressive disorder (MDD) Genome-Wide Association Studdies (GWAS) data from Wray et al.'s GWAS meta-analysis. Phenotypic data related to sleep were collected from the UK Biobank. Chronic pain data were obtained from the Finnish database.

RESULTS

MR analysis revealed significant genetic associations between MDD and chronic localized pain [IVW: odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.16-1.38, p = 2.52 × 10-7] as well as fibromyalgia (IVW: OR = 2.17, 95% CI = 1.34-3.52, p = .002). Genetic susceptibility for MDD was also associated with insomnia (IVW: OR = 1.10, 95% CI = 1.06-1.13, p = 3.57 × 10-8) and self-reported short sleep duration (IVW: OR = 1.03, 95% CI = 1.00-1.06, p = .047). The mediating effects of insomnia and fibromyalgia on the pathway from depression to chronic regional pain were 1.04 and 1.03, respectively, with mediation proportions of 12.8% and 15.2%. Insomnia mediated the pathway between depression and fibromyalgia with an effect of 1.12, accounting for 15.2% of the total effect.

CONCLUSION

This two-step MR analysis strengthens the evidence of genetic predictive associations between depression and chronic pain, highlighting the mediating roles of insomnia and short sleep duration. It further elucidates the specific roles of distinct sleep disorders, differentiating insomnia and short sleep duration from other sleep-related phenotypes.

Variability in the prevalence of depression among adults with chronic pain: UK Biobank analysis through clinical prediction models

BACKGROUND

The prevalence of depression among people with chronic pain remains unclear due to the heterogeneity of study samples and definitions of depression. We aimed to identify sources of variation in the prevalence of depression among people with chronic pain and generate clinical prediction models to estimate the probability of depression among individuals with chronic pain.

METHODS

Participants were from the UK Biobank. The primary outcome was a "lifetime" history of depression. The model's performance was evaluated using discrimination (optimism-corrected C statistic) and calibration (calibration plot).

RESULTS

Analyses included 24,405 patients with chronic pain (mean age 64.1 years). Among participants with chronic widespread pain, the prevalence of having a "lifetime" history of depression was 45.7% and varied (25.0-66.7%) depending on patient characteristics. The final clinical prediction model (optimism-corrected C statistic: 0.66; good calibration on the calibration plot) included age, BMI, smoking status, physical activity, socioeconomic status, gender, history of asthma, history of heart failure, and history of peripheral artery disease. Among participants with chronic regional pain, the prevalence of having a "lifetime" history of depression was 30.2% and varied (21.4-70.6%) depending on patient characteristics. The final clinical prediction model (optimism-corrected C statistic: 0.65; good calibration on the calibration plot) included age, gender, nature of pain, smoking status, regular opioid use, history of asthma, pain location that bothers you most, and BMI.

CONCLUSIONS

There was substantial variability in the prevalence of depression among patients with chronic pain. Clinically relevant factors were selected to develop prediction models. Clinicians can use these models to assess patients' treatment needs. These predictors are convenient to collect during daily practice, making it easy for busy clinicians to use them.

Serotonin Transporter (5-Hydroxytryptamine Transporter, SERT, SLC6A4) and Sodium-dependent Reuptake Inhibitors as Modulators of Pain Behaviors and Analgesic Responses

The serotonin transporter (5-hydroxytryptamine transporter [5-HTT], Serotonin Transporter (SERT), SLC6A4) modulates the activity of serotonin via sodium-dependent reuptake. Given the established importance of serotonin in the control of pain, 5-HTT has received much interest in studies of pain states and as a pharmacological target for serotonin reuptake inhibitors (SRIs). Animal models expressing varying levels of 5-HTT activity show marked differences in pain behaviors and analgesic responses, as well as many serotonin-related physiological effects. In humans, functional nucleotide variations in the SLC6A4 gene, which encodes the serotonin transporter 5-HTT, are associated with certain pathologic pain conditions and differences in responses to pharmacological therapy. These findings collectively reflect the importance of 5-HTT in the intricate physiology and management of pain, as well as the scientific and clinical challenges that need to be considered for the optimization of 5-HTT-related analgesic therapies. PERSPECTIVE: The serotonin transporter 5-HTT/SCL6A4 is sensitive to pharmacological SRIs. Experimental studies on the physiological functions of serotonin, as well as genetic mouse models and clinical phenotype/genotype correlations of nucleotide variation in the human 5-HTT/SCL6A4 gene, provide new insights for the use of SRIs in chronic pain management.

Demographics moderated the association of symptom burden with falls and fall-related outcomes

OBJECTIVES

To examine whether (1) prior-year symptom burden predicted later-year falls and fall-related outcomes and (2) demographics moderated the longitudinal effects of symptom burden on falls and fall-related outcomes among community-dwelling older adults.

METHODS

We used 2011-2018 National Health and Aging Trends Study data that included 9,060 community-dwelling older adults (contributed 34,327 observations). Falls and fall-related outcomes included self-reported falls, multiple falls, fear of falling (FOF), and FOF limiting activity. Symptom burden was defined as the presence of pain, insomnia, breathing difficulty, depressive symptoms, anxiety, and fatigue, and calculated the number of symptoms (range from 0 to 6). Binomial logistic regression was used to examine the associations between symptom burden and falls and fall-related outcomes and the moderation effects of demographic factors.

RESULTS

The majority of the sample were aged between 65 and 79 years old (57.7%), non-Hispanic White (70.5%), and female (58.4%). Each additional symptom was associated with an increased risk of falls (Adjusted Odds Ratio [AOR]: 1.13, 95% CI: 1.10-1.15), multiple falls (AOR: 1.15, 95% CI: 1.12-1.18), FOF (AOR: 1.20, 95% CI: 1.18-1.23), and FOF limiting activity (AOR: 1.24, 95% CI: 1.20-1.28). Age, race/ethnicity, education, and living arrangement statistically significantly moderated the relationships between symptom burden and falls and fall-related outcomes.

CONCLUSIONS

Symptom burden predicted falls, multiple falls, FOF and FOF limiting activity, and demographics may differentially modify this risk. Individually tailored symptom assessment and management plans should be incorporated into fall risk assessment and interventions for community-dwelling older adults living.

Assessment of relationships between frailty and chronic pain: a bidirectional two-sample Mendelian randomisation study

BACKGROUND

Previous observational studies have indicated a complex association between chronic pain and frailty. This study aimed to examine the bidirectional causal relationship between frailty and chronic pain and to quantify mediating effects of known modifiable risk factors.

METHODS

A bidirectional two-sample Mendelian randomisation (MR) analysis was applied in this study. Summary genome-wide association statistics for frailty, as defined by both frailty index (FI) and Fried Frailty Score (FFS), pain at seven site-specific chronic pain (SSCP) (headache, facial, neck/shoulder, stomach/abdominal, back, hip and knee) and multisite chronic pain (MCP) were extracted from populations of European ancestry. Genetic instrumental variables strongly correlated with each exposure were selected. The inverse-variance-weighted method was the primary method used in the MR, supplemented by a range of sensitivity and validation analyses. Two-step MR analysis was undertaken to evaluate the mediating effects of several proposed confounders.

RESULTS

Genetically predicted higher FI and FFS were associated with an increased risk of MCP and specific types of SSCP, including neck/shoulder pain, stomach/abdominal pain, back pain, hip pain and knee pain. In the reverse direction analysis, genetic liability to MCP was found to be associated with increased FI and FFS. These results remained consistent across sensitivity and validation assessments. Two-step MR suggested a mediating role for body mass index, smoking initiation, physical inactivity, educational attainment and depression.

CONCLUSIONS

Our research provided genetic evidence that the association between frailty and chronic pain was bidirectional where the coexistence of both conditions will exacerbate each other.

Spasmodic Dysphonia Patients' Perception of Pain with Botulinum Toxin Injections

OBJECTIVES

To evaluate spasmodic dysphonia patients' perception of pain associated with laryngeal botulinum toxin (BTX) injections and to determine factors associated with higher pain scores relative to other included patients.

METHODS

Prospective cohort study. Adult patients with adductor spasmodic dysphonia that presented to a tertiary laryngology practice for BTX injections were recruited from March to July 2022. Patients completed the visual analog scale (VAS) pre-procedure to quantify predicted pain. Ten minutes post-procedure they completed VAS and the short form McGill Pain Questionnaire (SF-MPQ). Factors that may affect pain were extracted from charts. Descriptive statistics, univariate, and multivariate analyses were conducted (alpha = 0.05).

RESULTS

One hundred and nineteen patients were included (63 ± 14 yo, 26% Male). SF-MPQ reported mild pain (4.12 ± 4.05 out of 45) with a pain intensity of none to mild (0.70 ± 0.89 out of 5). Bilateral injections yielded significantly higher SF-MPQ scores (5.19 ± 4.66) than unilateral injections (3.30 ± 3.30) (p = 0.012). There was a significant VAS reduction from pre 28.9 ± 24.6 mm (out of 10 mm) to post 24.5 ± 22.3 (p < 0.001). On multiple regression analyses, receiving a bilateral injection significantly (p < 0.05) contributed to a model that predicted higher pre-VAS (p = 0.013). Bilateral injections (p < 0.05) and higher VHI-10 (p < 0.05) contributed to a model that predicted higher total SF-MPQ (p = 0.001) and affective SF-MPQ (p = 0.001) scores. Not being a professional voice user (PVU) significantly (p < 0.05) contributed to a model that predicted higher post-VAS (p = 0.008) scores.

CONCLUSIONS

BTX injections were well tolerated with low pain scores. Factors associated with higher relative predicted or experienced pain included bilateral versus unilateral injection, PVU status, and higher VHI-10.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:240-246, 2024.

Feeling too low to be active: Physical inactivity mediates the relationship between mental and physical health

BACKGROUND

Physical inactivity is one of the most influential and pervasive risk factors for health problems. Therefore, public health experts call for interventions to promote physical activity across the lifespan. This study aimed to examine the role of mental health in physical inactivity and the subsequent role of physical activity in various aspects of physical health.

METHODS

Data were collected in the third wave of the European Health Interview Survey (EHIS) in Slovenia. A nationally representative sample of 9,900 people (49.6% male) aged 15 years or more (M = 49.2; SD = 18.9 years) provided self-reports on depression (PHQ-8), subjective well-being (MHC-SF), physical (in)activity, bodily pain, long-standing activity limitations, their general health status, and possible chronic diseases.

RESULTS

The results of a path analysis showed that depression had a positive effect and well-being had a negative effect on physical inactivity, which in turn contributed to the likelihood of severe bodily pain, activity limitations, poor self-rated health, and multimorbidity. Depression and well-being contributed to health-related outcomes directly and indirectly through physical inactivity.

LIMITATIONS

Because of the cross-sectional design, this study is limited in its ability to draw causal conclusions. All health data were self-reported.

CONCLUSIONS

Results suggest that high levels of depression and low levels of subjective well-being may be an early warning sign of physical health problems. Interventions aimed at preventing or reducing mental health problems and promoting positive mental health may benefit not only mental health per se, but also prevent physical inactivity and, consequently, physical health problems.

Potential Causal Association between Depression and Oral Diseases: A Mendelian Randomization Study

BACKGROUND

Globally, oral diseases are common, pose an economic burden, and significantly decline the quality of life of affected individuals. Recently, researchers have substantially highlighted the effect of depression on oral disease incidence and development. In this study, we elucidated the correlation between depression and oral diseases.

METHODS

Using two-sample Mendelian randomization (MR), the association between depression and the risk of 17 oral diseases was evaluated. Three methods were used to perform MR analysis: the inverse variance-weighted, weighted median, and MR-Egger methods. Furthermore, Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier test, and leave-one-out analysis were performed to analyze sensitivity.

RESULTS

After implementing multiple test corrections, we observed that genetic susceptibility to depression was associated with an increased risk of mouth ulcers, toothache, loose teeth, bleeding gums, painful gums, chronic periodontitis, chronic tonsil and adenoid diseases, peritonsillar abscess, and excessive tooth attrition. However, a causal relationship between depression and other oral diseases was not observed. Sensitivity analysis confirmed the robustness of the results.

CONCLUSIONS

We confirmed the causal relationship between depression and several oral diseases, thereby providing a novel viewpoint on the prevention and treatment of oral diseases. Our findings suggest the integration of depression control into routine clinical care to enhance the effectiveness of oral disease treatment.

Genome wide association joint analysis reveals 99 risk loci for pain susceptibility and pleiotropic relationships with psychiatric, metabolic, and immunological traits

Chronic pain is at epidemic proportions in the United States, represents a significant burden on our public health system, and is coincident with a growing opioid crisis. While numerous genome-wide association studies have been reported for specific pain-related traits, many of these studies were underpowered, and the genetic relationship among these traits remains poorly understood. Here, we conducted a joint analysis of genome-wide association study summary statistics from seventeen pain susceptibility traits in the UK Biobank. This analysis revealed 99 genome-wide significant risk loci, 65 of which overlap loci identified in earlier studies. The remaining 34 loci are novel. We applied leave-one-trait-out meta-analyses to evaluate the influence of each trait on the joint analysis, which suggested that loci fall into four categories: loci associated with nearly all pain-related traits; loci primarily associated with a single trait; loci associated with multiple forms of skeletomuscular pain; and loci associated with headache-related pain. Overall, 664 genes were mapped to the 99 loci by genomic proximity, eQTLs, and chromatin interaction and ~15% of these genes showed differential expression in individuals with acute or chronic pain compared to healthy controls. Risk loci were enriched for genes involved in neurological and inflammatory pathways. Genetic correlation and two-sample Mendelian randomization indicated that psychiatric, metabolic, and immunological traits mediate some of these effects.

Evidence for a causal effect of major depressive disorder, anxiety on prostatitis risk: A univariate and multivariate Mendelian randomization study

BACKGROUND

Observational studies have shown an association between major depressive disorder (MDD), anxiety, and prostatitis. However, the causal relationship between MDD, anxiety, and prostatitis remains controversial. Therefore, we aimed to use two-sample Mendelian randomization (MR) to assess the causal effects of MDD and anxiety on prostatitis.

METHODS

We conducted univariable and multivariable MR analyses using summary statistics from publicly available genome-wide association studies to estimate the causal relationships between MDD, anxiety, and prostatitis risk. In the main MR analysis, the inverse-variance weighted (IVW) method was used, while secondary methods included the weighted median, weighted mode, MR-Egger regression, and MR pleiotropy residual and outlier (MR-PRESSO) tests to detect and correct for the presence of pleiotropy.

RESULTS

MDD had 97 independent instrumental variables (IVs) and anxiety had 15 IVs. Univariable MR analysis showed that genetically determined MDD had a detrimental causal effect on prostatitis (IVW: odds ratio [OR] = 1.47, 95% confidence interval [CI] = 1.12-1.92, p = 0.005), while no causal relationship was found between anxiety and prostatitis (IVW: OR = 0.25, 95% CI = 0.02-2.82, p = 0.26). More convincingly, after adjusting for confounding factors such as body mass index, alcohol consumption, and smoking, the genetic liability for MDD remained associated with prostatitis risk, with no strong evidence of anxiety affecting prostatitis incidence.

CONCLUSION

This study supports the notion that MDD has a detrimental effect on prostatitis risk, and strategies focused on addressing MDD may be one of the cornerstones for treating prostatitis. The potential preventive value of treating MDD for prostatitis should be further investigated in future research.

Exploring the bidirectional relationship between pain and mental disorders: a comprehensive Mendelian randomization study

BACKGROUND

The close relationship between pain and mental health problems is well-known, and psychological intervention can provide an effective alternative to medication-based pain relief. However, previous studies on the connection between pain and psychological problems, the findings thus far have been inconclusive, limiting the potential for translating psychological interventions into clinical practice. To complement the gap, this study utilized genetic data and Mendelian randomization (MR) to examine the potential relationship between pain in different parts and common mental disorders.

METHODS

Based on the instrumental variables selected from the Genome-wide association study summary statistics of localized pain and mental disorders, we conducted bidirectional two-sample MR analyses to infer bidirectional causal associations between pain and mental disorders. The inverse-variance weighted MR method and MR-Egger were used as the primary statistical method according to the horizontal pleiotropy and heterogeneity level. We reported the odds ratio to infer the causal effect between pain and mental disorders. F statistic was calculated to measure the statistical efficacy of the analyses.

RESULTS

Insomnia is causally related to the genetic susceptibility of multisite pain including head (OR = 1.09, 95% CI: 1.06-1.12), neck/shoulder (OR = 1.12, 95% CI: 1.07-1.16), back (OR = 1.12, 95% CI: 1.07-1.18) and hip (OR = 1.08, 95% CI: 1.05-1.10). Reversely, headache (OR = 1.14, 95% CI: 1.05-1.24), neck/shoulder pain (OR = 1.95, 95% CI: 1.03-3.68), back pain (OR = 1.40, 95% CI: 1.22-1.60), and hip pain (OR = 2.29, 95% CI: 1.18-4.45) promote the genetic liability of insomnia. Depression is strongly associated with the predisposition of multisite pain including headache (OR = 1.28, 95% CI: 1.08-1.52), neck/shoulder pain (OR = 1.32, 95% CI: 1.16-1.50), back pain (OR = 1.35, 95% CI: 1.10-1.66) and stomach/abdominal pain (OR = 1.14, 95% CI: 1.05-1.25), while headache (OR = 1.06, 95% CI: 1.03-1.08), neck/shoulder (OR = 1.09, 95% CI: 1.01-1.17), back (OR = 1.08, 95% CI: 1.03-1.14), and stomach/abdominal pain (OR = 1.19, 95% CI: 1.11-1.26) are predisposing factors for depression. Additionally, insomnia is associated with the predisposition of facial, stomach/abdominal, and knee pain, anxiety was associated with the predisposition of neck/shoulder and back pain, while the susceptibilities of hip and facial pain are influenced by depression, but these associations were unidirectional.

CONCLUSIONS

Our results enhance the understanding of the complex interplay between pain and mental health and highlight the importance of a holistic approach to pain management that addresses both physical and psychological factors.

Association between Musculoskeletal Injuries and Depressive Symptoms among Athletes: A Systematic Review

Musculoskeletal (MSK) injuries have a significant physical and psychological influence on an athlete's life. A systematic review of prospective cohort, cross-sectional, and case-control studies was undertaken in this study to analyze the association between MSK injuries with depressive symptoms in athletes. We searched on PubMed, Web of Science, and Scopus, with data inception to 15 February 2023. The methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). Of the 3677 potential studies only nine were included. These studies showed a bidirectional association between MSK injuries and depressive symptoms. Athletes with MSK injuries had higher levels of depressive symptoms, which raises the likelihood of experiencing depression in the future. Women athletes had higher levels of depressive symptoms compared with men. The presence of depressive symptoms is a significant predictor of disability in athletes. Our findings suggest that coaches should be more aware of depressive symptoms, in order to prevent MSK injuries, and to monitor athletes following an MSK injury.

Association between dietary habits and the risk of migraine: a Mendelian randomization study

Objective

The important contribution of dietary triggers to migraine pathogenesis has been recognized. However, the potential causal roles of many dietary habits on the risk of migraine in the whole population are still under debate. The objective of this study was to determine the potential causal association between dietary habits and the risk of migraine (and its subtypes) development, as well as the possible mediator roles of migraine risk factors.

Methods

Based on summary statistics from large-scale genome-wide association studies, we conducted two-sample Mendelian randomization (MR) and bidirectional MR to investigate the potential causal associations between 83 dietary habits and migraine and its subtypes, and network MR was performed to explore the possible mediator roles of 8 migraine risk factors.

Results

After correcting for multiple testing, we found evidence for associations of genetically predicted coffee, cheese, oily fish, alcohol (red wine), raw vegetables, muesli, and wholemeal/wholegrain bread intake with decreased risk of migraine, those odds ratios ranged from 0.78 (95% CI: 0.63-0.95) for overall cheese intake to 0.61 (95% CI: 0.47-0.80) for drinks usually with meals among current drinkers (yes + it varies vs. no); while white bread, cornflakes/frosties, and poultry intake were positively associated with the risk of migraine. Additionally, genetic liability to white bread, wholemeal/wholegrain bread, muesli, alcohol (red wine), cheese, and oily fish intake were associated with a higher risk of insomnia and (or) major depression disorder (MDD), each of them may act as a mediator in the pathway from several dietary habits to migraine. Finally, we found evidence of a negative association between genetically predicted migraine and drinking types, and positive association between migraine and cups of tea per day.

Significance

Our study provides evidence about association between dietary habits and the risk of migraine and demonstrates that some associations are partly mediated through one or both insomnia and MDD. These results provide new insights for further nutritional interventions for migraine prevention.

The genetic architecture of pain intensity in a sample of 598,339 U.S. veterans

Chronic pain is a common problem, with more than one-fifth of adult Americans reporting pain daily or on most days. It adversely affects quality of life and imposes substantial personal and economic costs. Efforts to treat chronic pain using opioids played a central role in precipitating the opioid crisis. Despite an estimated heritability of 25-50%, the genetic architecture of chronic pain is not well characterized, in part because studies have largely been limited to samples of European ancestry. To help address this knowledge gap, we conducted a cross-ancestry meta-analysis of pain intensity in 598,339 participants in the Million Veteran Program, which identified 125 independent genetic loci, 82 of which are novel. Pain intensity was genetically correlated with other pain phenotypes, level of substance use and substance use disorders, other psychiatric traits, education level, and cognitive traits. Integration of the GWAS findings with functional genomics data shows enrichment for putatively causal genes (n = 142) and proteins (n = 14) expressed in brain tissues, specifically in GABAergic neurons. Drug repurposing analysis identified anticonvulsants, beta-blockers, and calcium-channel blockers, among other drug groups, as having potential analgesic effects. Our results provide insights into key molecular contributors to the experience of pain and highlight attractive drug targets.

A Shared Genetic Signature for Common Chronic Pain Conditions and its Impact on Biopsychosocial Traits

The multiple comorbidities & dimensions of chronic pain present a formidable challenge in disentangling its aetiology. Here, we performed genome-wide association studies of 8 chronic pain types using UK Biobank data (N =4,037-79,089 cases; N = 239,125 controls), followed by bivariate linkage disequilibrium-score regression and latent causal variable analyses to determine (respectively) their genetic correlations and genetic causal proportion (GCP) parameters with 1,492 other complex traits. We report evidence of a shared genetic signature across chronic pain types as their genetic correlations and GCP directions were broadly consistent across an array of biopsychosocial traits. Across 5,942 significant genetic correlations, 570 trait pairs could be explained by a causal association (|GCP| >0.6; 5% false discovery rate), including 82 traits affected by pain while 410 contributed to an increased risk of chronic pain (cf. 78 with a decreased risk) such as certain somatic pathologies (eg, musculoskeletal), psychiatric traits (eg, depression), socioeconomic factors (eg, occupation) and medical comorbidities (eg, cardiovascular disease). This data-driven phenome-wide association analysis has demonstrated a novel and efficient strategy for identifying genetically supported risk & protective traits to enhance the design of interventional trials targeting underlying causal factors and accelerate the development of more effective treatments with broader clinical utility. PERSPECTIVE: Through large-scale phenome-wide association analyses of >1,400 biopsychosocial traits, this article provides evidence for a shared genetic signature across 8 common chronic pain types. It lays the foundation for further translational studies focused on identifying causal genetic variants and pathophysiological pathways to develop novel diagnostic & therapeutic technologies and strategies.

Multisite chronic pain as a causal risk factor for coronary artery disease: findings from Mendelian randomization

ABSTRACT

The potential consequences of the number of chronic pain sites (referred to multisite chronic pain) on the risk of cardiovascular diseases (CVDs) remain unclear. We attempted to investigate the causality of multisite chronic pain with CVDs and its possible causal mediators. Using summary genome-wide association statistics, two-sample Mendelian randomization (MR) analyses were performed to assess whether multisite chronic pain has a causal effect on the 3 CVDs including coronary artery disease, atrial fibrillation, and stroke. We then conducted MR mediation analyses to establish whether body mass index (BMI), smoking, and depression causally mediate any association. Genetic liability to multisite chronic pain was associated with increased risk of coronary artery disease (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.19-1.95 per one increase in the number of pain locations) but not with atrial fibrillation or stroke. We also found positive causal effects of multisite chronic pain on BMI, smoking, and depression and causal effects of BMI, smoking, and depression on coronary artery disease. In multivariable MR analyses, the excess risk of coronary artery disease was attenuated after adjusting for BMI (OR 1.43, 95% CI 1.05-1.93), smoking (OR 1.49, 95% CI 1.11-2.00), depression (OR 1.44, 95% CI 1.03-2.01), and 3 risk factors combined (OR 1.34, 95% CI 0.88-2.05). Our findings demonstrated that multisite chronic pain led to higher risk of coronary artery disease, which is partly mediated through BMI, smoking, and depression.

Exploring the relationship between gratitude and depression among older adults with chronic low back pain: a sequential mediation analysis

Introduction

Gratitude has been identified as a key factor in a number of positive health-related outcomes; however, the mechanisms whereby gratitude is associated with well-being among older adults with chronic pain are poorly understood. Using the Positive Psychological Well-Being Model as a theoretical framework, the objective of the present study was to examine the serial mediating effects of social support, stress, sleep, and tumor necrosis factor-alpha (TNF-α) on the relationship between gratitude and depressive symptoms.

Methods

A total sample of 60 community-dwelling older adults with chronic low back pain (cLBP) provided blood samples for high-sensitivity TNF-α and completed the Gratitude Questionnaire, Perceived Stress Scale, and the PROMIS Emotional Support, Sleep Disturbance, and Depression forms. Descriptive statistics, correlation analyses, and serial mediation analyses were performed.

Results

Gratitude was negatively associated with perceived stress, sleep disturbance, and depression, and was positively associated with social support. No significant association was observed between gratitude and TNF-α. After controlling for age and marital status, analyses revealed that perceived stress and sleep disturbance sequentially mediated the association between gratitude and depressive symptoms.

Conclusion

Perceived stress and sleep disturbance may be potential mechanistic pathways by which gratitude impacts negative well-being. Targeting gratitude as a protective resource may be a potential therapeutic tool to improve psychological and behavioral outcomes in older adults with cLBP.

The pain and depressive symptoms cascade: A bidirectional analysis of the Mexican Health and Aging Study 2012-2015

OBJECTIVES

The association of pain and depression has not been evaluated in low- and middle-income countries, which have a disproportionate burden of pain compared to high-income countries.

METHODS

Using data from the Mexican Health and Aging Study (baseline, 2012; follow-up, 2015), we examined the bidirectional relationship between pain and depressive symptoms and identified shared predictors among community-dwelling participants ≥60 years (n = 7237). Multivariable logistic regressions models evaluated the association between (1) baseline pain and incident elevated depressive symptoms and (2) baseline depressive symptoms and incident pain, adjusting for demographic, socioeconomic, and health-related factors. Models included inverse probability weights and evaluated interactions by gender.

RESULTS

Participants (55.0% women) were on average 69.1 years old. Over half reported no pain (60.7%) and low/no depressive symptoms (67.9%) in 2012, of which, 20.2% reported elevated depressive symptoms and 25.3% self-reported pain in 2015. Baseline pain was associated with higher odds of incident elevated depressive symptoms (aOR 1.65; 95% CI, 1.41-1.93). Baseline elevated depressive symptoms were associated with higher odds of developing pain (aOR 1.57; 95% CI, 1.32-1.87). Age, gender, self-rated health, and activity of daily living limitations were shared risk factors for pain and elevated depressive symptomatology onset. Although the incidence of elevated depressive symptoms and pain was higher in women, there were no statistically significant interactions.

CONCLUSIONS

Older adults with pain or depression may be at risk for developing the other. These shared predictors could help identify patients in clinical settings, where pain and depression are often overlooked, reducing the cascading risk of this comorbidity.

Comorbidity and familial aggregation of back/neck pain in the NIMH Family Study of Affective Spectrum Disorders

OBJECTIVE

Back pain is associated with substantial Global Burden of Disease and is highly comorbid with mood and anxiety symptoms and syndromes. However, mechanisms underlying this association have not been well-elucidated. Here we apply data from the NIMH Family Study of Affective Spectrum Disorders to investigate the comorbidity, familial aggregation, and cross-aggregation of back/neck pain with mood disorder subtypes.

METHODS

The sample includes 519 probands and 560 interviewed first-degree relatives. Lifetime DSM-IV Bipolar I, Bipolar II, and Major Depressive Disorder [MDD] were derived from semi-structured diagnostic interviews. Lifetime history of back or neck pain and its age of onset were self-reported retrospectively. Familial aggregation and cross-aggregation were estimated via mixed effects models in probands and interviewed first-degree relatives, while heritability and co-heritability (endophenotypic ranking value [ERV]) were estimated using full pedigrees.

RESULTS

Over 45% of participants endorsed a history of back/neck pain. Back/neck pain was familial (adjusted odds ratio [aOR] 1.5, p = 0.04; h2 = 0.24, p = 0.009). Back/neck pain in probands was associated with MDD in relatives (aOR 1.5, p = 0.04; ERV = 0.17, p = 0.024), but not with bipolar disorder. Onset of back/neck pain occurred earlier in those with bipolar disorder compared to controls.

CONCLUSION

Findings suggest common familial risk factors underlying back/neck pain with MDD, whereas there was within-individual comorbidity of bipolar with back/neck pain. Future studies that identify common factors that lead to either back/neck pain or MDD can inform prevention and interventions.

Rehman A, Morris DW. Major Depressive Disorder: Existing Hypotheses about Pathophysiological Mechanisms and New Genetic Findings

Major depressive disorder (MDD) is a common mental disorder generally characterized by symptoms associated with mood, pleasure and effectiveness in daily life activities. MDD is ranked as a major contributor to worldwide disability. The complex pathogenesis of MDD is not yet understood, and this is a major cause of failure to develop new therapies and MDD recurrence. Here we summarize the literature on existing hypotheses about the pathophysiological mechanisms of MDD. We describe the different approaches undertaken to understand the molecular mechanism of MDD using genetic data. Hundreds of loci have now been identified by large genome-wide association studies (GWAS). We describe these studies and how they have provided information on the biological processes, cell types, tissues and druggable targets that are enriched for MDD risk genes. We detail our understanding of the genetic correlations and causal relationships between MDD and many psychiatric and non-psychiatric disorders and traits. We highlight the challenges associated with genetic studies, including the complexity of MDD genetics in diverse populations and the need for a study of rare variants and new studies of gene-environment interactions.