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

The inflammatory and genetic mechanisms underlying the cumulative effect of co-occurring pain conditions on depression

Chronic pain conditions frequently coexist and share common genetic vulnerabilities. Despite evidence showing associations between pain and depression, the additive effect of co-occurring pain conditions on depression risk and the underlying mechanisms remain unclear. Leveraging data from 431,038 UK Biobank participants with 14-year follow-up, we found a significantly increased risk of depression incidence in individuals reporting pain, irrespective of body site or duration (acute or chronic), compared with pain-free individuals. The depression risk increased with the number of co-occurring pain sites. Mendelian randomization supported potential causal inference. We constructed a composite pain score by combining individual effects of acute or chronic pain conditions across eight body sites in a weighted manner. We found that depression risks increased monotonically in parallel with composite pain scores. Moreover, some inflammatory markers, including C-reactive protein, partially mediated the association between composite pain scores and depression risk. Considering the high prevalence of comorbid depression and pain, pain screening may help identify high-risk individuals for depression.

Association of chronic pain with incidence and progression of cardiometabolic multimorbidity in middle-aged and older populations: a multicohort study

Introduction

Chronic pain is associated with single cardiometabolic diseases (CMDs). Less is known about the association of chronic pain with the co-occurrence of multiple CMDs, known as cardiometabolic multimorbidity (CMM).

Objectives

This study aims to examine the association between chronic pain and incidence of CMM and if it existed, to what extent chronic pain relates to the progression of specific CMD-related multimorbidity (MM).

Methods

We pooled individual-level data of 59,134 participants from 4 cohort studies across 18 countries between 2010 and 2020. Participants aged 45 years or older, free of CMDs (diabetes, heart diseases, and stroke), and with self-reported chronic pain status at baseline were included. Multinomial logistic regression was performed on the association of chronic pain with incident CMM and the progression of specific CMD-related MM.

Results

One-third (21,204) of participants reported chronic pain at baseline. After 8 to 9 years, 1344 (2.3%) developed CMM. Chronic pain was associated with the onset of each CMD (odds ratio [OR] range 1.12-1.37) and CMM combinations (OR range 1.57-2.09). It is also linked with the increased odds of more CMDs (1, 2, and 3) during the follow-up. For example, OR increased from 1.31 for individuals with one CMD, to 1.57 for those with 2 CMDs, to 2.09 for those with 3 CMDs. Chronic pain was also associated with developing all CMD-related MM (OR range 1.26-1.88). Compared with those with diabetes only, participants with chronic pain were more likely to progress to diabetes and heart diseases, as well as diabetes, heart diseases, and stroke.

Conclusion

Chronic pain is associated with incidence and progression of CMM, whose management should be considered in primary and secondary prevention of CMM among middle-aged and older populations.

Association of Short-term Pain and Chronic Pain Intensity With Cardiometabolic Multimorbidity Progression: A Multistate Markov Model Analysis

BACKGROUND

The impact of pain intensity on the progression trajectories of cardiometabolic multimorbidity (CMM) is not well understood. We attempted to dissect the relationship of short-term pain (STP) and chronic pain intensity with the temporal progression of CMM.

METHODS

We conducted a prospective cohort study based on the UK Biobank participants. Incident cases of cardiometabolic diseases (CMDs) were identified based on self-reported information and multiple health-related records in the UK Biobank. CMM was defined as the occurrence of at least 2 CMDs, including heart failure (HF), ischemic heart disease (IHD), stroke, and type 2 diabetes (T2D). The pain intensity was categorized into 5 levels based on pain duration and the number of sites involved, including chronic widespread pain (CWSP), chronic multilocation pain (CMLP), chronic single-location pain (CSLP), STP, and free-of-pain (FOP). Multistate models were used to assess the impact of pain intensity on the CMM trajectories from enrollment to initial cardiometabolic disease (ICMD), subsequently to CMM, and ultimately to death.

RESULTS

A total of 429,145 participants were included. Over the course of a 12.8-year median follow-up, 13.1% (56,137/429,145) developed ICMD, 19.6% (10,979/56,137) further progressed to CMM, and a total of 5.3% (22,775/429,145) died. Compared with FOP, CMLP (hazard ratio [HR], 1.11; 95% confidence interval [CI], 1.06-1.17) and CWSP (HR, 1.26; 95% CI, 1.13-1.42) elevated the risk of transitioning from ICMD to CMM. STP (HR, 0.89; 95% CI, 0.82-0.96), CSLP (HR, 0.88; 95% CI, 0.82-0.95), and CMLP (HR, 0.87; 95% CI, 0.81-0.93) lowered the risk of transition from ICMD to mortality, and STP also reduced the risk of transition from enrollment to mortality (HR, 0.94; 95% CI, 0.89-0.98). The results of disease-specific transitions revealed that the influence of pain intensity varied across transitional stages. Specifically, CMLP and CWSP heightened the risk of conversion from T2D or IHD to CMM, whereas only CWSP substantially elevated the transition risk from HF to CMM.

CONCLUSIONS

Our results highlighted reductions in chronic pain may mitigate both the onset and progression of CMM, potentially having an important impact on future revisions of cardiometabolic and pain-related guidelines.

Causal relationship between educational attainment and chronic pain: A Mendelian randomization study

Educational attainment (EA) is often used as a symbol of socioeconomic status and is associated with several diseases. However, uncertainty remains regarding the potential relationship between EA and chronic pain. This study aimed to evaluate the potential causal association between EA and chronic pain. The primary method employed in Mendelian randomization (MR) analysis was inverse-variance weighted method. Additionally, MR-Egger intercept, Cochran Q, and MR-PRESSO statistical analyses were conducted to assess potential pleiotropy and heterogeneity. The MR analysis provided evidence that genetically predicted additional education significantly reduced the risk of chronic pain. Specifically, this genetic factor may reduce multisite chronic pain by 27.6%, and chronic widespread pain by 3.8%. The results of sensitivity analysis indicated the reliability of our causal estimates. Higher levels of EA may provide protection against chronic pain risk. Enhancing education, narrowing social and economic disparities may help alleviate the burden of chronic pain.

Exploring Sex Differences in Pain Manifestation of Coronary Artery Disease through Mendelian Randomization

Pain manifestation following coronary artery disease (CAD) disease differs between men and women. Here, we aimed to provide evidence favoring possible differences in pain manifestation between men and women following CAD using Mendelian randomization (MR). We used summary-level data from sex-stratified genome-wide association studies on CAD and self-reported and clinically diagnosed chest, neck and shoulder, back, and facial pain using data from the UK Biobank cohort (N > 450,000) followed by two-sample MR (sensitivity) analyses. We identified 32 and 19 independent genetic variants associated with CAD for men and women, respectively, as instrumental variables. Genetically influenced CAD was associated with a higher risk of self-reported chest pain in both men (OR: 1.27, CI: 1.2-1.33) and women (OR: 1.44, CI: 1.20-1.73), with similar results for clinically diagnosed chest pain (men OR: 1.22, CI: 1.17-1.26; women OR: 1.31, CI: 1.18-1.46). In addition, in women only, genetically influenced CAD was associated with a higher risk of back pain (OR: 1.35, CI: 1.03-1.66) and neck and shoulder pain (OR: 1.22, CI: 0.91-1.63) (p-values for interaction with men: 0.030 and 0.041, respectively). Sensitivity analysis did not indicate the results were biased by directional pleiotropy. We found evidence, based on genetic predisposition for CAD, for different pain manifestations of CAD in men and women. While CAD was associated with chest pain in both sexes, we only found evidence for a higher risk of back pain and neck and shoulder pain in women, supporting common notions that women may present more often with uncharacteristic anginal symptoms.

Mediating effect of depressive symptoms on the relationship of chronic pain and cardiovascular diseases among Chinese population: Evidence from the CHARLS

OBJECTIVE

Few studies have examined the direct or indirect effect of chronic pain on cardiovascular diseases (CVD) within Chinese population. The objective aimed to investigate the mediating role of depressive symptoms between chronic pain and CVD.

METHODS

6522 participants from China Health and Retirement Longitudinal Study were included in this retrospective cohort study. The main endpoint was the occurrence of CVD. Weighted multivariate logistic regression was used to assess the association between chronic pain and depressive symptoms. Distribution-of-product method was employed to examine the mediation effect of depressive symptoms. Subgroup analyses were performed.

RESULTS

219 developed CVD at the end of follow-up period. After adjusting all confounding variables, chronic pain was associated with increased risk of depressive symptoms in total population [odds ratio (OR) = 3.85, 95%confidence interval (CI): 3.35-4.42]. Among total population, there was a positive association of chronic pain and CVD [risk ratio (RR)a = 2.00, 95% CI: 1.33-3.00] (total effect). After further adjusting depressive symptoms, the association between chronic pain and CVD was significant (RRb = 1.67, 95% CI: 1.16-2.41) (direct effect). According to the distribution-of-product test, we observed a mediating effect of depressive symptoms on the relationship between chronic pain and CVD with the percentage of mediation of 32.8%. The mediating effect of depression was observed in individuals of aged45-65 years old, female participants, participants who never drinking and not have hypertension.

CONCLUSION

Chronic pain was positively associated with CVD for Chinese population, and depressive symptoms was considered to mediate the association between chronic pain and CVD.

Effects of menstrual disorders and dysmenorrhea on cardiovascular disease: a Mendelian randomization study

Background

Observational studies have demonstrated associations between menstrual disorders, dysmenorrhea, and cardiovascular disease (CVD). However, it remains unclear whether these associations are causal. This study is to investigate whether menstrual disorders and dysmenorrhea causally affect the risk of CVD.

Methods

The summary data for menstrual disorders (excessive menstruation and irregular menses) and dysmenorrhea were obtained from FinnGen study, summary data for CVD were obtained from UK Biobank and meta-analysis. The inverse-variance-weighted method was mainly used in the Mendelian randomization for causality analysis. Sensitivity analyses were performed by several methods under different model assumptions.

Results

Genetic liability to excessive menstruation was associated with higher risk of atrial fibrillation (odds ratio (OR), 1.078 [95% confidence interval (CI), 1.015-1.145]; P=0.014), but a lower risk of hypertension (OR, 0.994 [95% CI: 0.989-0.999]; P=0.016). Irregular menses was associated with higher risk of atrial fibrillation (OR, 1.095 [95% CI: 1.015-1.182]; P=0.02), hypertension (OR, 1.007 [95% CI: 1.000-1.013]; P=0.047), myocardial infarction (OR, 1.172 [95% CI: 1.060-1.295]; P=0.02), ischemic heart disease, (OR, 1.005 [95% CI: 1.000-1.010]; P=0.037) and coronary heart disease (OR, 1.004 [95% CI: 1.001-1.008]; P=0.026). Dysmenorrhea was associated with higher risk of atrial fibrillation (OR, 1.052 [95% CI: 1.014-1.092]; P=0.008) and Ischemic stroke (cardioembolic) (OR, 1.122 [95% CI: 1.002-1.257]; P=0.046). After Benjamini-Hochberg correction, irregular menses was associated with higher risk of myocardial infarction.

Conclusion

We confirmed a causal relationship of excessive menstruation, irregular menses and dysmenorrhea on cardiovascular outcomes independent of sex hormone levels, with an emphasis on the link between irregular menses and myocardial infarction. These clinical features can be utilized as markers to identify women at higher risk of developing CVD in the future, recommending early clinical intervention of menstrual diseases.

Genetic insights into associations of multisite chronic pain with common diseases and biomarkers using data from the UK Biobank

BACKGROUND

Chronic pain is a common, complex, and challenging condition, for which specialised healthcare is required. We investigated the relationship between multisite chronic pain (MCP) and different disease traits identify safe biomarker interventions that can prevent MCP.

METHODS

Univariable and multivariable Mendelian randomisation (MR) analysis were conducted to investigate associations between MCP and 36 common diseases in the UK Biobank. Subsequently, we estimated the potential effect of expression of 4774 proteins on MCP utilising existing plasma protein quantitative trait locus data. For the significant biomarkers, we performed phenome-wide MR (Phe-MR) with 1658 outcomes to predict potential safety profiles linked to biomarker intervention.

RESULTS

Multisite chronic pain had a substantial impact on psychiatric and neurodevelopmental traits (major depression and attention deficit hyperactivity disorder), cardiovascular diseases (myocardial infarction, coronary artery disease, and heart failure), respiratory outcomes (asthma, chronic obstructive pulmonary disease, and sleep apnoea), arthropathies, type 2 diabetes mellitus, and cholelithiasis. Higher genetically predicted levels of S100A6, DOCK9, ferritin, and ferritin light chain were associated with a risk of MCP, whereas PTN9 and NEUG were linked to decreased MCP risk. Phe-MR results suggested that genetic inhibition of DOCK9 increased the risk of 21 types of disease, whereas the other biomarker interventions were relatively safe.

CONCLUSIONS

We established that MCP has an effect on health conditions covering various physiological systems and identified six novel biomarkers for intervention. In particular, S100A6, PTN9, NEUG, and ferritin light chain represent promising targets for MCP prevention, as no significant side-effects were predicted in our study.

Multisite chronic pain and the risk of autoimmune diseases: A Mendelian randomization study

Background

Accumulating evidence has demonstrated that an association between chronic pain and autoimmune diseases (AIDs). Nevertheless, it is unclear whether these associations refer to a causal relationship. We used a two-sample Mendelian randomization (MR) method to determine the causal relationship between chronic pain and AIDs.

Methods

We assessed genome-wide association study (GWAS) summary statistics for chronic pain [multisite chronic pain (MCP) and chronic widespread pain (CWP)], and eight common AIDs, namely, amyotrophic lateral sclerosis (ALS), celiac disease (CeD), inflammatory bowel disease (IBD), multiple sclerosis (MS), rheumatoid arthritis (RA), systemic lupus Erythematosus (SLE), type 1 diabetes (T1D) and psoriasis. Summary statistics data were from publicly available and relatively large-scale GWAS meta-analyses to date. The two-sample MR analyses were first performed to identify the causal effect of chronic pain on AIDs. The two-step MR and multivariable MR were used to determine if mediators (BMI and smoking) causally mediated any connection and to estimate the proportion of the association mediated by these factors combined.

Results

With the utilization of MR analysis, multisite chronic pain was associated with a higher risk of MS [odds ratio (OR) = 1.59, 95% confidence interval (CI) = 1.01-2.49, P = 0.044] and RA (OR = 1.72, 95% CI = 1.06-2.77, P = 0.028). However, multisite chronic pain had no significant effect on ALS (OR = 1.26, 95% CI = 0.92-1.71, P = 0.150), CeD (OR = 0.24, 95% CI = 0.02-3.64, P = 0.303), IBD (OR = 0.46, 95% CI = 0.09-2.27, P = 0.338), SLE (OR = 1.78, 95% CI = 0.82-3.88, P = 0.144), T1D (OR = 1.15, 95% CI = 0.65-2.02, P = 0.627) or Psoriasis (OR = 1.59, 95% CI = 0.22-11.26, P = 0.644). We also found positive causal effects of MCP on BMI and causal effects of BMI on MS and RA. Moreover, there were no causal connections between genetically predicted chronic widespread pain and the risk of most types of AIDs disease.

Conclusion

Our MR analysis implied a causal relationship between MCP and MS/RA, and the effect of MCP on MS and RA may be partially mediated by BMI.