Autonomic function and rheumatoid arthritis: a systematic review

Enhanced Association of Novel Cardiovascular Biomarkers Fetuin-A and Catestatin with Serological and Inflammatory Markers in Rheumatoid Arthritis Patients

Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with increased cardiovascular disease (CVD) risk and mortality. This work aimed to evaluate the serum levels of the novel CV biomarkers fetuin-A (fet-A), Dickkopf-1 (DKK-1), galectin-3 (Gal-3), interleukin-32 (IL-32), and catestatin (CST) in RA patients and their associations with RA parameters and CVD markers. A cohort of 199 RA patients was assessed for traditional CVD risk factors, RA disease activity, and biomarker levels. Carotid ultrasound was used to measure carotid intima-media thickness (cIMT) and carotid plaque presence (cPP). Multivariate analyses examined correlations between biomarkers and RA parameters, serological markers, and CVD markers. Adjusted models showed that elevated CST expression levels were associated with rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) positivity (OR = 2.45, p = 0.0001 and OR = 1.48, p = 0.04, respectively) in the overall cohort and for RF in men and women, respectively. In addition, fet-A concentration was inversely associated with the erythrocyte sedimentation rate (ESR) in the overall cohort (β = -0.15, p = 0.038) and in women (β = -0.25, p = 0.004). Fet-A levels were also negatively correlated with disease activity (DAS28-ESR) scores (β = -0.29, p = 0.01) and fibrinogen concentration (β = -0.22, p = 0.01) in women. No adjusted associations were observed for Gal-3, DKK-1 or IL32 concentration. The study revealed no significant associations between the biomarkers and cIMT or cPP. The measurement of CST and fet-A levels could enhance RA patient management and prognosis. However, the utility of biomarkers for evaluating CV risk via traditional surrogate markers is limited, highlighting the need for continued investigations into their roles in RA.

Update: factors influencing heart rate variability-a narrative review

Objective

Heart rate variability (HRV) is an important non-invasive marker for the assessment of an organism's autonomic physiological regulatory pathways. Lower HRV has been shown to correlate with increased mortality. HRV is influenced by various factors or diseases. The aim of this narrative review is to describe the current state of knowledge on factors influencing HRV and their significance for interpretation.

Methods

The narrative review only included reviews, meta-analyses, and cohort studies which were published until 2021. HRV confounders were grouped into four categories (non-influenceable physiological factors, diseases, influenceable lifestyle factors and external factors).

Results

The review found that HRV was decreased not only in non-influenceable physiological factors (e.g., age, gender, ethnicity) but also in connection with various number of acute and chronic diseases (e.g., psychiatric diseases, myocardial infarction, heart failure), influenceable lifestyle factors (e.g., alcohol abuse, overweight, physical activity), and external factors (e.g., heat, noise, shift work, harmful- and hazardous substances).

Conclusion

In order to improve the quality of HRV studies and to ensure accurate interpretation, it is recommended that confounders be taken into account in future diagnostic measurements or measurements in the workplace (e.g., as part of health promotion measures) in order to counteract data bias.

Cardiovascular Autonomic Dysfunction in Hospitalized Patients with a Bacterial Infection: A Longitudinal Observational Pilot Study in the UK

PURPOSE

A temporal reduction in the cardiovascular autonomic responses predisposes patients to cardiovascular instability after a viral infection and therefore increases the risk of associated complications. These findings have not been replicated in a bacterial infection. This pilot study will explore the prevalence of cardiovascular autonomic dysfunction (CAD) in hospitalized patients with a bacterial infection.

METHODS

A longitudinal observational pilot study was conducted. Fifty participants were included: 13 and 37 participants in the infection group and healthy group, respectively. Recruitment and data collection were carried out during a two-year period. Participants were followed up for 6 weeks: all participants' cardiovascular function was assessed at baseline (week 1) and reassessed subsequently at week 6 so that the progression of the autonomic function could be evaluated over that period of time. The collected data were thereafter analyzed using STATA/SE version 16.1 (StataCorp). The Fisher Exact test, McNemar exact test, Mann-Whitney test and Wilcoxon test were used for data analysis.

RESULTS

32.4% of the participants in the healthy group were males (n = 12) and 67.6% were females (n = 25). Participants' age ranged from 33 years old to 76 years old with the majority being 40-60 years of age (62.1%) (Mean age 52.4 SD = 11.4). Heart rate variability (HRV) in response to Valsalva Maneuver, metronome breathing, standing and sustained handgrip in the infection group was lower than in the healthy group throughout the weeks. Moreover, both the HRV in response to metronome breathing and standing up showed a statistically significant difference when the mean values were compared between both groups in week 1 (p = 0.03 and p = 0.013). The prevalence of CAD was significantly higher in the infection group compared to healthy volunteers, both at the beginning of the study (p = 0.018) and at the end of follow up (p = 0.057), when all patients had been discharged.

CONCLUSIONS

CAD, as assessed by the HRV, is a common finding during the recovery period of a bacterial infection, even after 6 weeks post-hospital admission. This may increase the risk of complications and cardiovascular instability. It may therefore be of value to conduct a wider scale study to further evaluate this aspect so recommendations can be made for the cardiovascular autonomic assessment of patients while they are recovering from a bacterial infectious process.

Osteoarthritis patients exhibit an autonomic dysfunction with indirect sympathetic dominance

BACKGROUND

Osteoarthritis (OA) is a chronic degenerative joint disease causing limited mobility and pain, with no curative treatment available. Recent in vivo studies suggested autonomic alterations during OA progression in patients, yet clinical evidence is scarce. Therefore, autonomic tone was analyzed in OA patients via heart rate variability (HRV) measurements.

METHODS

Time-domain (SDRR, RMSSD, pRR50) and frequency-domain (LF, HF, LF/HF) HRV indices were determined to quantify sympathetic and parasympathetic activities. In addition, perceived stress, WOMAC pain as well as serum catecholamines, cortisol and dehydroepiandrosterone-sulphate (DHEA-S) were analyzed. The impact of the grade of disease (GoD) was evaluated by linear regression analysis and correlations with clinical data were performed.

RESULTS

GoD significantly impacted the autonomic tone in OA patients. All time-domain parameters reflected slightly decreased HRV in early OA patients and significantly reduced HRV in late OA patients. Moreover, frequency-domain analysis revealed decreased HF and LF power in all OA patients, reflecting diminished parasympathetic and sympathetic activities. However, LF/HF ratio was significantly higher in early OA patients compared to late OA patients and implied a clear sympathetic dominance. Furthermore, OA patients perceived significantly higher chronic stress and WOMAC pain levels compared to healthy controls. Serum cortisol and cortisol/DHEA-S ratio significantly increased with GoD and positively correlated with WOMAC pain. In contrast, serum catecholamines only trended to increase with GoD and pain level.

CONCLUSIONS

This prospective study provides compelling evidence of an autonomic dysfunction with indirect sympathetic dominance in early and late knee OA patients for the first time based on HRV analyses and further confirmed by serum stress hormone measurements. Increased sympathetic activity and chronic low-grade inflammation in OA as well as in its major comorbidities reinforce each other and might therefore create a vicious cycle. The observed autonomic alterations coupled with increased stress and pain levels highlight the potential of HRV as a prognostic marker. In addition, modulation of autonomic activity represents an attractive future therapeutic option.

Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science

This updated guideline replaces the "Guideline for the application of heart rate and heart rate variability in occupational medicine and occupational health science" first published in 2014. Based on the older version of the guideline, the authors have reviewed and evaluated the findings on the use of heart rate (HR) and heart rate variability (HRV) that have been published in the meantime and incorporated them into a new version of this guideline.This guideline was developed for application in clinical practice and research purposes in the fields of occupational medicine and occupational science to complement evaluation procedures with respect to exposure and risk assessment at the workplace by the use of objective physiological workload indicators. In addition, HRV is also suitable for assessing the state of health and for monitoring the progress of illnesses and preventive medical measures. It gives an overview of factors influencing the regulation of the HR and HRV at rest and during work. It further illustrates methods for measuring and analyzing these parameters under standardized laboratory and real workload conditions, areas of application as well as the quality control procedures to be followed during the recording and evaluation of HR and HRV.

Stimulation of the vagus nerve as a therapeutic principle

Modulation of the parasympathetic tone leads to extensive physiological reactions at several levels, including the decreased production of proinflammatory cytokines. Many studies have demonstrated that chronic inflammatory diseases are associated with reduced parasympathetic and increased sympathetic activities. Moreover, it was demonstrated that a low parasympathetic and a high sympathetic activity in patients with rheumatoid arthritis (RA) predicts a poor therapeutic response to anti-tumor necrosis factor (TNF) treatment compared to RA patients with a more balanced autonomic nervous system. The autonomic equilibrium could be restored by electrical stimulation of the vagus nerve. Considering the patients who do not sufficiently respond to the available drugs, patients for whom the effectiveness of the drugs wanes over time, or have drug-related adverse events, a nonpharmacological approach such as bioelectronics might be a useful supplement as an instrument in the successful extension of the therapeutic armamentarium for rheumatic diseases; however, there is a great need for further studies and the development of novel therapeutic strategies in the field of neuroimmunology.

Targeting Pathways and Integrated Approaches to Treat Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic symmetrical systemic disorder that not only affects joints but also other organs such as heart, lungs, kidney, and liver. Approximately there is 0.5%-1% of the total population affected by RA. RA pathogenesis still remains unclear due to which its appropriate treatment is a challenge. Further, multitudes of factors have been reported to affect its progression i.e. genetic factor, environmental factor, immune factor, and oxidative factor. Therapeutic approaches available for the treatment of RA include NSAIDs, DMARDs, enzymatic, hormonal, and gene therapies. But most of them provide the symptomatic relief without treating the core of the disease. This makes it obligatory to explore and reach the molecular targets for cure and long-term relief from RA. Herein, we attempt to provide extensive overlay of the new targets for RA treatment such as signaling pathways, proteins, and receptors affecting the progression of the disease and its severity. Precise modification in these targets such as suppressing the notch signaling pathway, SIRT 3 protein, Sphingosine-1-phosphate receptor and stimulating the neuronal signals particularly efferent vagus nerve and SIRT 1 protein may offer long term relief and potentially diminish the chronicity. To target or alter the novel molecules and signaling pathway a specific delivery system is required such as liposome, nanoparticles and micelles and many more. Present review paper discusses in detail about novel targets and delivery systems for treating RA.

Hyposalivation and periodontal disease as oral non-articular characteristics in rheumatoid arthritis

OBJECTIVE

To investigate the association among rheumatoid arthritis (RA), saliva production, and periodontal status.

METHODS

An observational study was carried out on 103 subjects with RA and 103 without RA matched by sex and age. Rheumatologic evaluation included serological and clinical variables. A full mouth periodontal examination was performed according to the American Academy of Periodontology (1999). Resting and stimulated whole salivary flows were determined after spiting during 5 min.

RESULTS

RA was associated with a higher prevalence of severe periodontitis (12% vs. 4%), with a marked reduction in resting and stimulated saliva production, and with a higher prevalence of resting (19% vs. 0%) and also stimulated hyposalivation (54% vs. 10%), compared with the control group. The differences in mean resting and stimulated salivary flows between RA and control groups persisted after the exclusion of people with hyposalivation. Saliva production was not associated with the presence or the severity of periodontal disease, or with the rheumatic clinical characteristics of the patients.

CONCLUSIONS

More than 50% of people with RA have some degree of reduction in their salivary flows, an affection not associated with the periodontal status or rheumatic activity, which are the expression of the two related inflammatory diseases. The influence of autonomic dysfunction on hyposalivation can be considered. While periodontitis would be a disease-associated comorbidity of RA, poor saliva production should be included among the extra-articular manifestations. Key Points • Rheumatoid arthritis patients are more prone to suffer from periodontitis and/or hyposalivation. • Periodontal disease is more prevalent in people with rheumatoid arthritis and also an association was found between the severities of both pathologies. • More than 50% of people with RA would have some degree of reduction in their salivary flows, an affection not associated with the periodontal status or rheumatic activity. • Reduced saliva production in rheumatoid arthritis patients should be included among the extra-articular manifestations.

Autonomic Dysfunction and Cardiovascular Risk in Patients with Rheumatoid Arthritis: Can Heart Rate Variability Analysis Contribute to a Better Evaluation of the Cardiovascular Profile of a Patient?

(1) Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease of autoimmune etiology. Increased scientific evidence suggests that immune-mediated inflammatory dis-eases are associated with autonomic nervous system (ANS) dysfunction. Studies proved that autonomic imbalance is correlated with RA evolution and may explain augmented cardiovascular pathology and mortality not attributable to classical risk factors. (2) Methods: 75 patients (25 males, 50 females) with RA were submitted to standard ECG recording and 24 h Holter monitoring. Twenty-five healthy patients were used as controls. Both time (SDNN, SDANN, SDANN Index, RRmed, rMSSD, and pNN50) and frequency domain (TP, VLF, HF, LF and LF/HF) heart rate variability (HRV) parameters were obtained. Parameters were compared to controls, and correlations with the QTc-interval and inflammatory status expressed through the C-reactive protein (CRP) were evaluated. (3) Results: In patients with a CRP > 5 mg/L, HRV parameters were lower compared to controls and to patients with a CRP ≤ 5 mg/L. All HRV parameters generated by Holter monitoring are negatively correlated with CRP levels and QTc values. The number of premature ventricular contractions (PVC) recorded is correlated with SDNN, SDANN, and LF/HF values. (4) Conclusions: Our study supports recent data suggesting that in RA there is an autonomic system dysfunction strongly connected with the inflammatory status of the patient. The autonomic dysfunction can contribute to the increased risk of cardiovascular death observed in patients with RA.

Heart rate variability and cardiovascular risk factors in patients with rheumatoid arthritis: A longitudinal study

BACKGROUND

It is established that the risk of cardiovascular disease (CVD) is increased in patients with Rheumatoid Arthritis (RA). Heart rate variability (HRV) is a method for evaluating the activity in the cardiac autonomic nervous system. Our aim was to assess the longitudinal development of HRV in patients with RA and compare with healthy controls. Furthermore, we wanted to investigate associations between HRV, inflammatory disease activity and cardiovascular complications in patients with RA over time.

METHOD

HRV was assessed with frequency-domain analysis at baseline and after five years in 50 patients with early RA, all being younger than 60 years. HRV indices were age-adjusted based on the estimated age-dependency in 100 age and sex matched healthy controls. Additionally, clinical data including serological markers, disease activity, and blood pressure were collected from the patients. Eleven years after inclusion CVD was assessed.

RESULTS

At baseline, patients with RA presented with lower HRV compared to controls during deep breathing (6 breaths/min), paced normal breathing (12 breaths/min) and after passive tilt to the upright position. No significant change in HRV was observed at the five-year follow-up. A significant negative correlation was found between HRV parameters and systolic blood pressure (SBP) at baseline. A significant positive correlation was found between heart rate and inflammatory markers at baseline but not after five years. Nine patients had developed CVD after 11 years, but no significant association was found with baseline HRV data.

CONCLUSION

This study showed that patients with RA have autonomic imbalance both at an early stage of the disease and after five years, despite anti-rheumatic medication, but no correlation between HRV and inflammation markers were observed. Reduced HRV was also significantly negatively correlated with increased SBP. Hypertension is a common finding in patients with RA. Thus, significant decline of HRV could be a useful early marker for development of hypertension in patients with RA.

Chronic β-adrenergic stress contributes to cardiomyopathy in rodents with collagen-induced arthritis

Patients with rheumatoid arthritis (RA) have a much higher incidence of cardiac dysfunction, which contributes to the high mortality rate of RA despite anti-arthritic drug therapy. In this study, we investigated dynamic changes in cardiac function in classic animal models of RA and examined the potential effectors of RA-induced heart failure (HF). Collagen-induced arthritis (CIA) models were established in rats and mice. The cardiac function of CIA animals was dynamically monitored using echocardiography and haemodynamics. We showed that cardiac diastolic and systolic dysfunction occurred in CIA animals and persisted after joint inflammation and that serum proinflammatory cytokine (IL-1β, TNF-α) levels were decreased. We did not find evidence of atherosclerosis (AS) in arthritic animals even though cardiomyopathy was significant. We observed that an impaired cardiac β1AR-excitation contraction coupling signal was accompanied by sustained increases in blood epinephrine levels in CIA rats. Furthermore, serum epinephrine concentrations were positively correlated with the heart failure biomarker NT-proBNP in RA patients (r2 = +0.53, P < 0.0001). In CIA mice, treatment with the nonselective βAR blocker carvedilol (2.5 mg·kg-1·d-1, for 4 weeks) or the specific GRK2 inhibitor paroxetine (2.5 mg·kg-1·d-1, for 4 weeks) effectively rescued heart function. We conclude that chronic and persistent β-adrenergic stress in CIA animals is a significant contributor to cardiomyopathy, which may be a potential target for protecting RA patients against HF.

Autonomic dysfunction and cardiovascular risk in psoriatic arthritis

Psoriatic arthritis (PsA) is an inflammatory disease with a high prevalence of cardiovascular (CV) events due to traditional cardiovascular risk factors and increased systemic inflammation. In this review, our objectives were to (i) evaluate the cardiovascular events and risk factors and (ii) investigate the relationship between autonomic dysfunction and CV diseases in PsA. A systematic review of the literature was done on the Medline/PubMed, Scopus, and the Directory of Open Access Journals databases between January 2017 and July 2022. After screening and exclusions, 73 studies were included for the final review. Patients with PsA have a greater risk of CV diseases and increased traditional CV risk factors, including hypertension, diabetes mellitus, obesity, metabolic syndrome, and dyslipidemia. Although autonomic dysfunction is more common in PsA than in the general population, its relationship with increased CV diseases in these patients is still unclear. Limitations in explaining CV risk in these patient groups complicate patient assessment as cardiovascular risk factors are linked to the morbidity and mortality of PsA, and it is essential to improve an optimal screening and management strategy for CV disease. All CV risk scoring systems cannot fully assess the CV risk in these patients, so in addition to scoring systems, carotid ultrasound evaluation may be a part of the CV evaluation.

Heat of the night: sleep disturbance activates inflammatory mechanisms and induces pain in rheumatoid arthritis

Sleep has a homeostatic role in the regulation of the immune system and serves to constrain activation of inflammatory signalling and expression of cellular inflammation. In patients with rheumatoid arthritis (RA), a misaligned inflammatory profile induces a dysregulation of sleep-wake activity, which leads to excessive inflammation and the induction of increased sensitivity to pain. Given that multiple biological mechanisms contribute to sleep disturbances (such as insomnia), and that the central nervous system communicates with the innate immune system via neuroendocrine and neural effector pathways, potential exists to develop prevention opportunities to mitigate the risk of insomnia in RA. Furthermore, understanding these risk mechanisms might inform additional insomnia treatment strategies directed towards steering and reducing the magnitude of the inflammatory response, which together could influence outcomes of pain and disease activity in RA.

Autonomic responses to aerobic and resistance exercise in patients with chronic musculoskeletal pain: A systematic review

BACKGROUND

It is unknown whether patients with chronic musculoskeletal pain (CMP) show autonomic dysregulation after exercise, and the interventional effects of exercise on the autonomic dysregulation have not been elucidated. The objectives of this study were to reveal acute autonomic responses after aerobic and resistance exercises and the interventional effects of both exercises on autonomic dysregulation in patients with CMP.

METHODS

A systematic search using nine electronic databases was performed based on three key search terms: "chronic musculoskeletal pain," "autonomic nervous system," and "exercise." Data were extracted from measurements of the autonomic nervous system and pain.

RESULTS

We found a total of 1170 articles; 17 were finally included, incorporating 12 observational and five interventional studies. Although a comparator has not been specified, healthy controls were compared to patients with CMP in observational studies. Three of five interventional studies were pre-post study with healthy controls as a comparator or no controls. The other two interventional studies were randomized controlled trial with a different treatment e.g., stretching. There were four good, 10 fair, and three poor-quality articles. The total number of participants was 617, of which 551 were female. There was high heterogeneity among the five disease conditions and nine outcome measures. Following one-time exposure to aerobic and resistance exercises, abnormal autonomic responses (sympathetic activation and parasympathetic withdrawal), which were absent in healthy controls, were observed in patients with CMP. The effects of aerobic and resistance exercise as long-term interventions were unclear since we identified both positive effects and no change in the autonomic activities in patients with CMP.

CONCLUSIONS

This study indicates dysfunctional autonomic responses following one-time exposure to exercise and inconsistent interventional effects in the autonomic activities in patients with CMP. Appropriate therapeutic dose is necessary for studying the management of autonomic regulation and pain after exercise.

[Stimulation of the vagus nerve as a therapeutic principle. German Version]

Modulation of the parasympathetic tone leads to extensive physiological reactions at several levels, including the decreased production of proinflammatory cytokines. Many studies have demonstrated that chronic inflammatory diseases are associated with reduced parasympathetic and increased sympathetic activities. Moreover, it was demonstrated that a low parasympathetic and a high sympathetic activity in patients with rheumatoid arthritis (RA) predicts a poor therapeutic response to anti-tumor necrosis factor (TNF) treatment compared to RA patients with a more balanced autonomic nervous system. The autonomic equilibrium could be restored by electrical stimulation of the vagus nerve. Considering the patients who do not sufficiently respond to the available drugs, patients for whom the effectiveness of the drugs wanes over time, or have drug-related adverse events, a nonpharmacological approach such as bioelectronics might be a useful supplement as an instrument in the successful extension of the therapeutic armamentarium for rheumatic diseases; however, there is a great need for further studies and the development of novel therapeutic strategies in the field of neuroimmunology.

The autonomic and nociceptive response to acute exercise is impaired in people with knee osteoarthritis

Objectives

An acute bout of exercise typically leads to short term exercise induced hypoalgesia (EIH), but this response is more variable in many chronic pain populations, including knee osteoarthritis (OA) and fibromyalgia (FM). There is evidence of autonomic nervous system (ANS) dysfunction in some chronic pain populations that may contribute to impaired EIH, but this has not been investigated in people with knee OA. The aim of this study was to assess the acute effects of isometric exercise on the nociceptive and autonomic nervous systems in people with knee OA and FM, compared to pain-free controls.

Methods

A cross-sectional study was undertaken with 14 people with knee OA, 13 people with FM, and 15 pain free controls. Across two experimental sessions, baseline recordings and the response of the nociceptive and autonomic nervous systems to a 5-min submaximal isometric contraction of the quadriceps muscle was assessed. The nociceptive system was assessed using pressure pain thresholds at the knee and forearm. The ANS was assessed using high frequency heart rate variability, cardiac pre-ejection period, and electrodermal activity. Outcome measures were obtained before and during (ANS) or immediately after (nociceptive) the acute bout of exercise.

Results

Submaximal isometric exercise led to EIH in the control group. EIH was absent in both chronic pain groups. Both chronic pain groups showed lower vagal activity at rest. Furthermore, people with knee OA demonstrated reduced vagal withdrawal in response to acute isometric exercise compared to controls. Sympathetic reactivity was similar across groups.

Discussion

The findings of reduced tonic vagal activity and reduced autonomic modulation in response to isometric exercise raise the potential of a blunted ability to adapt to acute exercise stress and modulate nociception in people with knee OA. The impairment of EIH in knee OA may, in part, be due to ANS dysfunction.

Inflammation mediates approximately one quarter of excess relative all-cause mortality in persons with rheumatoid arthritis: the Trøndelag Health Study

Inflammation may contribute to excess mortality in rheumatoid arthritis (RA) patients. We investigated associations to all-cause mortality of the inflammation markers high-sensitivity C-reactive protein (CRP), lactoferrin (neutrophil activation marker), and neopterin (monocyte activation marker). From the population-based Trøndelag Health Study (3rd wave 2006-2008), 316 RA patients and 43,579 controls were included. Lactoferrin and neopterin were quantified in a nested cohort (n = 283 RA patients, n = 3698 controls). Follow-up was until death found by linkage to the Norwegian Cause of Death Registry or 31.12.2018. All-cause mortality was analyzed using Cox regression and Cox regression-based mediation analysis. Having RA (hazard ratio (HR): 1.25, 95%CI: 1.00, 1.56, p = 0.048), and CRP ≥ 3 mg/L (HR: 1.50, 95%CI: 1.41, 1.60, p < 0.001) were associated with all-cause mortality. The overall excess relative mortality risk of having RA was 38%. CRP ≥ 3 mg/L mediated approximately 1/4 of this risk (p < 0.001). In the nested cohort, CRP ≥ 3 mg/L (HR: 1.51, 95%CI: 1.26, 1.80, p < 0.001) and neopterin (HR: 1.17, 95%CI: 1.01, 1.36, p = 0.031) were associated with all-cause mortality. In conclusion, CRP levels ≥ 3 mg/L mediated approximately a quarter of the 38% excess relative all-cause mortality risk associated with RA. Using definitions of RA remission with emphasis both on joint status and the level of general inflammation may help guide the most efficient treatment regimens.

Investigating the Dose-Response Relationship between Deep Breathing and Heart Rate Variability in Healthy Participants and Across-Days Reliability in Patients with Rheumatoid Arthritis and Systemic Lupus Erythematosus

Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE) are associated with autonomic dysfunction, potentially through reduced vagus nerve tone. Vagus nerve stimulation has been proposed as an anti-inflammatory treatment, and it can be performed through deep breathing (DB) exercises. In this study, the dose-response relationship between DB exercises and heart rate variability (HRV) was investigated in healthy participants and reliability across days in patients with RA and SLE. On three separate days, 41 healthy participants performed DB for: 5, 15, or 30 min. On two separate days, 52 RA or SLE patients performed DB with the dose associated with the highest HRV increase in healthy participants. The HRV was estimated from ECG-recordings recorded prior and post the DB exercises. Increases in dose led to larger HRV-responses. Thirty minutes led to the largest HRV-response. In the RA and SLE patients, this dose increased the HRV-parameters consistently across the two days, indicating reliability. DB increases HRV in healthy participants and RA or SLE patients, which indicates stimulation of the vagus nerve. Of the tested durations, 30 min of DB was the optimal period of stimulation. A potential anti-inflammatory effect of DB exercises should be investigated in future studies.

Interplay of Environmental, Individual and Genetic Factors in Rheumatoid Arthritis Provocation

In this review, we explore systemization of knowledge about the triggering effects of non-genetic factors in pathogenic mechanisms that contribute to the development of rheumatoid arthritis (RA). Possible mechanisms involving environmental and individual factors in RA pathogenesis were analyzed, namely, infections, mental stress, sleep deprivation ecology, age, perinatal and gender factors, eating habits, obesity and smoking. The non-genetic factors modulate basic processes in the body with the impact of these factors being non-specific, but these common challenges may be decisive for advancement of the disease in the predisposed body at risk for RA. The provocation of this particular disease is associated with the presence of congenital loci minoris resistentia. The more frequent non-genetic factors form tangles of interdependent relationships and, thereby, several interdependent external factors hit one vulnerable basic process at once, either provoking or reinforcing each other. Understanding the specific mechanisms by which environmental and individual factors impact an individual under RA risk in the preclinical stages can contribute to early disease diagnosis and, if the factor is modifiable, might be useful for the prevention or delay of its development.

The Interplay between Autonomic Nervous System and Inflammation across Systemic Autoimmune Diseases

The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation.

Heart rate and heart rate variability in patients with chronic inflammatory joint disease: the role of pain duration and the insular cortex

Background

Chronic inflammatory joint diseases (CIJD) have been linked to increased cardiovascular morbidity and mortality. A decisive reason could be a dysregulation of the autonomic nervous system, which is responsible for the control of cardiovascular function. So far, the cause of changes in autonomic nervous system functions remains elusive. In this study, we investigate the role of chronic pain and the insular cortex in autonomic control of cardiac functioning in patients with CIJD.

Methods

We studied the autonomic nervous system through the assessment of heart rate and heart rate variability (HRV) at rest and under cognitive stimulation. Furthermore, we investigated insular cortex volume by performing surface-based brain morphometry with FreeSurfer. For this study, 47 participants were recruited, 22 individual age- and sex-matched pairs for the magnetic resonance imaging analyses and 14 for the HRV analyses. All available patients’ data were used for analysis.

Results

Pain duration was negatively correlated with the resting heart rate in patients with chronic inflammatory joint diseases (n = 20). In a multiple linear regression model including only CIJD patients with heart rate at rest as a dependent variable, we found a significant positive relationship between heart rate at rest and the volume of the left insular cortex and a significant negative relationship between heart rate at rest and the volume of the right insular cortex. However, we found no significant differences in HRV parameters or insular cortex volumes between both groups.

Conclusions

In this study we provide evidence to suggest insular cortex involvement in the process of ANS changes due to chronic pain in CIJD patients.

The study was preregistered with the German Clinical Trials Register (https://www.drks.de; DRKS00012791; date of registration: 28 July 2017).

Elevated Peripheral T Helper Cells Are Associated With Atrial Fibrillation in Patients With Rheumatoid Arthritis

Patients with rheumatoid arthritis (RA) have a significantly high risk of atrial fibrillation (AF). This study aimed to compare the absolute and relative changes in peripheral T cells in patients with RA who were also affected with and without AF. To help make an early diagnosis and prevent the initiation and progression of AF, the changes in the lymphocyte subsets were assessed in RA patients with and without AF. A propensity score matching (PSM) system (1:3) was used to perform a matched case-control study with 40 RA-AF cases and 120 RA controls. Changes in the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), anti-citrullinated peptide antibody (ACPA), and rheumatoid factor (RF) were examined. The percentage and absolute number of T, B, natural killer (NK), T helper (Th)1, Th2, Th17, and T-regulatory (Treg) cells in the peripheral blood of patients with and without RA-AF were determined using flow cytometry. Univariate and multivariate analyses were performed to determine the association between peripheral lymphocytes and RA-AF. Demographic data, ESR, CRP, ACPA, and the percentage, as well as the absolute value of B, NK, Th2, and Treg cells, showed no significant differences between the propensity score-matched groups of RA and RA-AF. Meanwhile, the absolute number and percentage of Th1 cells, the absolute number of Th17 cells, the ratio of Th1/Treg, Th17/Treg, and RF were significantly higher in patients with RA-AF than those in the control groups (P < 0.05). Univariate and multivariate logistic regression analyses also revealed that the percentage of Th1 cells, the absolute number of Th17 cells, and the ratio of Th1/Treg were associated with a significantly higher risk of AF. This PSM study demonstrated that the incidence of AF was higher in RA patients with Th cell immunological derangements.

Animal models to study pathogenesis and treatments of cardiac disorders in rheumatoid arthritis: Advances and challenges for clinical translation

Although cardiac diseases such as acute myocardial infarction, heart failure and arrhythmias are the leading cause of cardiovascular complications in rheumatoid arthritis (RA), their pathogenesis is far from being understood and optimal therapeutic options to treat specifically these disorders in RA are lacking. Preclinical studies on animal models of arthritis can help to decipher the complex link between arthritis and the heart, and to identify critical pathways and novel therapeutic targets. This review presented the available data on cardiac disorders in animal models of RA, as well as the current knowledge on pathophysiology and pharmacology of these disorders. Future directions for translational studies in a cardiorheumatic perspective are proposed.

Triggers of Cardiovascular Diseases in Rheumatoid Arthritis

The risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) is higher than that in patients without RA, and it is even higher than that in patients with diabetes. Autoimmune-mediated inflammation is observed in patients with RA, resulting in endothelial dysfunction, oxidative stress and activation, and vascular migration of white blood cells. Traditionally, RA-associated CVD was assumed to be mediated by disease-related inflammation, resulting in atherosclerosis (AS). However, this concept has been challenged because treatment with anti-rheumatic drugs, such as methotrexate or proinflammatory cytokine antagonists, such as tumor necrosis factor-alpha (TNF-α) inhibitors, did not reduce the risk of CVD in patients with RA. Current cardiovascular guidelines recommend screening and treatment of CVD risk factors in patients with RA but without clear biomarkers and treatment goals. There is no scientific basis for establishing therapeutic targets for cardiovascular risk factors in RA. Numerous studies have shown that the mechanism of early cardiac dysfunction in patients with RA may occur prior to AS. Therefore, it is crucial to explore the related mechanisms to prevent early cardiac dysfunction in patients with RA.

Non-invasive vagus nerve stimulation for rheumatoid arthritis: a proof-of-concept study

BACKGROUND

Vagus nerve stimulation delivered with an implanted device has been shown to improve rheumatoid arthritis severity. We aimed to investigate the safety and efficacy of non-invasive stimulation of the auricular branch of the vagus nerve for the treatment of patients with moderately to severely active rheumatoid arthritis.

METHODS

This prospective, multicentre, open-label, single-arm proof-of-concept study enrolled patients aged 18-80 years with active rheumatoid arthritis who had an inadequate response to conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and up to one biological DMARD. Biological DMARDs were stopped at least 4 weeks before enrolment and concomitant use was not allowed during the study. All eligible participants were assigned to use a non-invasive, wearable vagus nerve stimulation device for up to 30 min per day, which delivered pulses of 20 kHz. Follow-up visits occurred at week 1, week 2, week 4, week 8, and week 12 after the baseline visit. The primary endpoint was the mean change in Disease Activity Score of 28 joints with C-reactive protein (DAS28-CRP) at week 12 compared with baseline. Secondary endpoints included the mean change in the Health Assessment Questionnaire-Disability Index (HAQ-DI), the proportion of patients with a minimal clinically important difference of 0·22 on HAQ-DI, the proportion achieving American College of Rheumatology (ACR) 20, ACR50, and ACR70 response, and safety analysis. This study is registered with ClinicalTrials.gov (NCT04116866).

FINDINGS

Of 35 patients screened for eligibility, 30 (86%) were enrolled at six centres in Spain between Dec 27, 2018, and Oct 24, 2019, of whom 27 (90%) completed the week 12 visit. The mean change in DAS28-CRP at 12 weeks was -1·4 (95%CI -1·9 to -0·9; p<0·0001) from a mean baseline of 5·3 (SD 1·0). 11 (37%) of 30 patients reached DAS28-CRP of 3·2 or less, and seven (23%) patients reached DAS28-CRP of less than 2·6 at week 12. The mean HAQ-DI change was -0·5 (95%CI -0·7 to -0·2; p<0·0001) from a mean baseline of 1·6 (SD 0·7), and 17 (57%) patients reached a minimal clinically important difference of 0·22 or more. ACR20 responses were reached by 16 (53%) patients, ACR50 responses by 10 (33%) patients, and ACR70 by five (17%) patients. Four adverse events were reported, none of which were serious and all of which resolved without intervention.

INTERPRETATION

Use of the device was well tolerated, and patients had clinically meaningful reductions in DAS28-CRP. This was an uncontrolled, open-label study, and the results must be interpreted in this context. Further evaluation in larger, controlled studies is needed to confirm whether this non-invasive approach might offer an alternative treatment for rheumatoid arthritis.

FUNDING

Nēsos.

Pain: A Review of Interleukin-6 and Its Roles in the Pain of Rheumatoid Arthritis

Pain is a major and common symptom reported as a top priority in patients with rheumatoid arthritis (RA). Intuitively, RA-related pain is often considered to be a natural consequence of peripheral inflammation, so treatment of RA is expected to manage pain concurrently as part of inflammation control. However, pain in patients with RA can be poorly correlated with objective measures of inflammation, for example, in patients who are otherwise in remission. Joint damage appears to account for only a fraction of this residual pain. Emerging evidence suggests that alteration of peripheral and central pain processing contributes to RA-related pain; this is parallel to, but somewhat independent of, joint inflammation. Interleukin (IL)-6 is a proinflammatory cytokine that contributes to the pathogenesis of RA. It exerts systemic effects via signaling through soluble forms of the IL-6 receptor (“trans-signaling”). Evidence from preclinical studies demonstrates that intra-articular IL-6 can produce long-lasting peripheral sensitization to mechanical stimulation and suggests an important role for IL-6 in central pain sensitization. This may be partly explained by its ability to activate neurons through trans-signaling, affecting nociceptive plasticity and nerve fiber regrowth. Local activity at neuron endings may culminate in altered pain processing in the central nervous system because of persistent signaling from sensitized peripheral neurons. Peripheral and central sensitization can promote the development of chronic pain, which can have a significant impact on patients’ health and quality of life. A proportion of pain in RA may be more appropriately managed as an entity separate from inflammation. Both the peripheral and central nervous systems should be recognized as important potential systems targeted by RA. The substantial burden of RA-related chronic pain suggests that pain should be a key focus in RA management and should be assessed and addressed early and separately from the inflammatory component.

The Link Between Autonomic Nervous System and Rheumatoid Arthritis: From Bench to Bedside

Neuronal stimulation is an emerging field of research focused on the management and treatment of various diseases through the reestablishment of physiological homeostasis. Electrical vagus nerve stimulation has recently been proposed as a revolutionary therapeutic option for rheumatoid arthritis (RA) in combination with or even as a replacement for conventional and biological drugs. In the past few years, disruption of the autonomic system has been linked to RA onset and activity. Novel research on the link between the autonomic nervous system and the immune system (immune-autonomics) has paved the way for the development of innovative RA management strategies. Clinical evidence supports this approach. Cardiovascular involvement, in terms of reduced baroreflex sensitivity and heart rate variability-derived indices, and mood disorders, common comorbidities in patients with RA, have been linked to autonomic nervous system dysfunction, which in turn is influenced by increased levels of circulating pro-inflammatory cytokines. This narrative review provides an overview of the autonomic nervous system and RA connection, discussing most of the common cardiac and mental health-related RA comorbidities and their potential relationships to systemic and joint inflammation.

Increased sympathetic and haemodynamic responses to exercise and muscle metaboreflex activation in post-menopausal women with rheumatoid arthritis

KEY POINTS

Rheumatoid arthritis (RA) patients present exacerbated blood pressure responses to exercise, but little is known regarding the underlying mechanisms involved.  This study assessed autonomic and haemodynamic responses to exercise and to the isolated activation of muscle metaboreflex in post-menopausal women with RA.  Participants with RA showed augmented pressor and sympathetic responses to exercise and to the activation of muscle metaboreflex. These responses were associated with multiple pro- and anti-inflammatory cytokines and with pain.  The results of the present study support the suggestion that an abnormal reflex control of circulation is an important mechanism underlying the exacerbated cardiovascular response to exercise and increased cardiovascular risk in RA.

ABSTRACT

Studies have reported abnormal cardiovascular responses to exercise in rheumatoid arthritis (RA) patients, but little is known regarding the underlying mechanisms involved. This study assessed haemodynamic and sympathetic responses to exercise and to the isolated activation of muscle metaboreflex in women diagnosed with RA. Thirty-three post-menopausal women diagnosed with RA and 10 matched controls (CON) participated in this study. Mean arterial pressure (MAP), heart rate (HR) and muscle sympathetic nerve activity (MSNA frequency and incidence) were measured during a protocol of isometric knee extension exercise (3 min, 30% of maximal voluntary contraction), followed by post-exercise ischaemia (PEI). Participants with RA showed greater increases in MAP and MSNA during exercise and PEI than CON (ΔMAP_exercise  = 16 ± 11 vs. 9 ± 6 mmHg, P = 0.03; ΔMAP_PEI  = 15 ± 10 vs. 5 ± 5 mmHg, P = 0.001; ΔMSNA_exercise  = 17 ± 14 vs. 7 ± 9 bursts min^-1 , P = 0.04; ΔMSNA_PEI  = 14 ± 10 vs. 6 ± 4 bursts min^-1 , P = 0.04). Autonomic responses to exercise showed significant (P < 0.05) association with pro- (i.e. IFN-γ, IL-8, MCP-1 and TNFα) and anti-inflammatory (i.e. IL-1ra and IL-10) cytokines and with pain. In conclusion, post-menopausal women with RA showed augmented pressor and sympathetic responses to exercise and to the activation of muscle metaboreflex. These findings provide mechanistic insights that may explain the abnormal cardiovascular responses to exercise in RA.

Proarrhythmic electrophysiological and structural remodeling in rheumatoid arthritis

Chronic inflammatory disorders, including rheumatoid arthritis (RA), are associated with a twofold increase in the incidence of sudden cardiac death (SCD) compared with the healthy population. Although this is partly explained by an increased prevalence of coronary artery disease, growing evidence suggests that ischemia alone cannot completely account for the increased risk. The present review explores the mechanisms of cardiac electrophysiological remodeling in response to chronic inflammation in RA. In particular, it focuses on the roles of nonischemic structural remodeling, altered cardiac ionic currents, and autonomic nervous system dysfunction in ventricular arrhythmogenesis and SCD. It also explores whether common genetic elements predispose to both RA and SCD. Finally, it evaluates the potential dual effects of disease-modifying therapy in both diminishing and promoting the risk of ventricular arrhythmias and SCD.

Cardiovascular risk in persons at risk of developing rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is associated with an increased cardiovascular disease (CVD) risk which may start even before diagnosis. To explore this CVD risk prior to RA, we determined multiple risk factors and two 10-year clinical risk scores in a cohort of individuals at-risk of RA. We also analyzed associations with arthritis development and autoantibody status and compared a subset of at-risk individuals to an age and sex matched seronegative control group.

Methods

In a cohort of 555 consecutive arthralgia patients positive for rheumatoid factor (RF) and / or anti-citrullinated protein antibody (ACPA) we retrospectively identified patients with preclinical arthritis (i.e. those who developed arthritis), and non-arthritis patients (those without arthritis development during maximum 5 years follow up). Demographics, CVD risk factors and the 10-year cardiovascular risk according to the SCORE and QRISK3 system were determined at baseline.

Results

Preclinical arthritis patients (n = 188) had a higher heart rate (68 vs 63 bpm, p = 0.048) and lower cholesterol (5.2 mmol/l vs 5.5, p = 0.006), HDL (1.0 mmol/l vs 1.1, p0.003) and ApoB (0.85 g/l vs 0.91, p = 0.011) compared to non-arthritis patients (n = 367). Lipid levels were associated with ACPA status in both the preclinical arthritis and non-arthritis group. Ten-year CVD risk scores did not differ between preclinical arthritis and non-arthritis patients, in total, 7% (SCORE) and 8% (QRISK3) of seropositive arthralgia patients were classified as high risk. Seropositive at-risk patients (n = 71) had higher total cholesterol (5.4 vs 4.9, p<0.001), TC/HDL ratio (4.0 vs 3.0, p<0.001), triglycerides (1.4 vs 1.0, p = 0.001), ApoB (1.0 vs 0.9, p = 0.019) and 10-year risk scores (median SCORE 1.0 vs 0.0, p = 0.030 and median QRISK3 4.4 vs 3.1, p<0.001) compared to seronegative controls.

Conclusion

Our results suggest that lipid changes commence prior to RA diagnosis and that ACPAs might play a role.

Cardiac Autonomic Control in Women with Rheumatoid Arthritis During the Glittre Activities of Daily Living Test

Background: Cardiovascular autonomic dysfunction is one of the most common complications in rheumatoid arthritis (RA), which can be assessed by heart rate variability (HRV) analysis. Because the autonomic nervous system plays an important role in orchestrating the cardiovascular response to stressors, assessing HRV during exercise is critical. The Glittre Activities of Daily Living test (GA-T) was recently proposed as a multitask field test that requires the performance of the upper and lower limbs, both of which are affected in individuals with RA. Objectives: This study was conducted to evaluate autonomic impairment by HRV in women with RA using the GA-T and to correlate these changes with physical functioning and muscle strength. Methods: This cross-sectional study enrolled 20 women (median [interquartile range]: age 55 [47.5 - 68.8] years) with RA (time since diagnosis: 15 [6.50 - 23.5] years) who underwent HRV assessment during GA-T. They also underwent physical functioning assessment through the Health Assessment Questionnaire Disability Index (HAQ-DI) and handgrip strength (HGS) and quadriceps strength (QS) measures. Results: The GA-T time exhibited significant correlations with the following HRV indices: root mean square of successive differences (RMSSD, rs = -0.451, P = 0.041), proportion of iRR differing by > 50 ms from previous intervals (pNN50, rs = -0.697, P = 0.0006), high frequency (HF, rs = -0.693, P = 0.0007), standard deviation of the points perpendicular to the line-of-identity (SD1, rs = -0.476, P = 0.034), and approximate entropy (ApEn, rs = 0.545, P = 0.013). In addition, the HAQ-DI exhibited significant correlations with the following HRV indices: pNN50 (rs = -0.467, P = 0.038) and HF (rs = -0.444, P = 0.049). We did not observe significant correlation between the HRV indices during the GA-T and the muscle strength measures (HGS and QS). Conclusions: In women with RA, the longer the required to perform the GA-T the worse their parasympathetic modulation, sympathetic-vagal imbalance, and complexity of the autonomic nervous system (i.e., increased index of ApEn) were. Physical functioning level was also related to vagal modulation.

Ganglionic Acetylcholine Receptor Antibodies and Autonomic Dysfunction in Autoimmune Rheumatic Diseases

Autonomic neuropathy has been reported in autoimmune rheumatic diseases (ARD) including Sjögren’s syndrome, systemic sclerosis, rheumatoid arthritis, and systemic lupus erythematosus. However, the pathophysiological mechanism underlying autonomic dysfunction remains unknown to researchers. On the other hand, autoimmune autonomic ganglionopathy (AAG) is an acquired immune-mediated disorder, which causes dysautonomia that is mediated by autoantibodies against ganglionic acetylcholine receptors (gAChRs). The purpose of this review was to describe the characteristics of autonomic disturbance through previous case reports and the functional tests used in these studies and address the importance of anti-gAChR antibodies. We have established luciferase immunoprecipitation systems to detect antibodies against gAChR in the past and determined the prevalence of gAChR antibodies in various autoimmune diseases including AAG and rheumatic diseases. Autonomic dysfunction, which affects lower parasympathetic and higher sympathetic activity, is usually observed in ARD. The anti-gAChR antibodies may play a crucial role in autonomic dysfunction observed in ARD. Further studies are necessary to determine whether anti-gAChR antibody levels are correlated with the severity of autonomic dysfunction in ARD.

Autoimmune Autonomic Disorders

PURPOSE OF REVIEW

Autonomic disorders sometimes occur in the context of systemic autoimmune disease or as a direct consequence of autoimmunity against the nervous system. This article provides an overview of autonomic disorders with potential autoimmune etiology.

RECENT FINDINGS

Recent evidence highlights a close association between the autonomic nervous system and inflammation. The autonomic nervous system regulates immune function, and autonomic manifestations may occur in a number of systemic autoimmune diseases. In a few instances, autoimmunity directly influences autonomic function. Autoimmune autonomic ganglionopathy is the prototypic antibody-mediated autonomic disorder. Over time, a better understanding of the clinical spectrum of autoimmune autonomic ganglionopathy, the significance of ganglionic nicotinic acetylcholine receptor antibodies, other immune-mediated autonomic neuropathies, and autonomic manifestations of other systemic or neurologic autoimmune disorders has emerged.

SUMMARY

Autoimmune autonomic disorders may be challenging, but correct identification of these conditions is important. In some cases, potential exists for effective immunomodulatory treatment.

Heart rate variability in atrial fibrillation: The balance between sympathetic and parasympathetic nervous system

BACKGROUND

Atrial fibrillation (AF) is the commonest abnormal heart rhythm with significant related morbidity and mortality. Several pathophysiologic mechanisms have been advocated to explain the onset of AF. There has been increasing evidence that abnormalities of the autonomic nervous system (ANS) that includes sympathetic, parasympathetic and intrinsic neural network are involved in the pathogenesis of AF. This review will consider the anatomical and pathophysiological concepts of the cardiac neuronal network and discuss how it can be investigated.

DESIGN

Relevant articles for this review were selected primarily from Ovid Medline and Embase databases (see appendix). We searched for key terms "atrial fibrillation," "AF," "autonomic dysfunction," "autonomic nervous system," "heart rate variability" and "HRV" to gather relevant studies. Duplicate papers were excluded.

RESULTS

Heart is richly innervated by autonomic nerves. Both sympathetic and parasympathetic systems interact in developing AF along with cardiac ganglionated plexi (GP). Thus autonomic dysfunction is present in AF. There are methods including selective ablation that reduce autonomic innervation and show to reduce the incidence of spontaneous or induced atrial arrhythmias. Heart rate variability (HRV) is a useful tool to assess sympathetic and parasympathetic influences on disease states. HRV can be improved following intervention and is thus a useful application in assessing autonomic dysfunction in patients with AF.

CONCLUSION

ANS plays a crucial role in the development, propagation and complexity of AF. Assessment of the autonomic involvement in the propagation of AF may help in explaining why certain patients with AF do not benefit from cardioversion or ablation.

[Cardiac arrhythmias in patients with chronic autoimmune diseases]

Chronic inflammation due to autoimmune diseases is associated with a higher rate of supraventricular and ventricular arrhythmias leading to an increased risk for cardiovascular morbidity and mortality. Involvement of the cardiac conduction system is common in patients with chronic autoimmune diseases, although the penetrance of clinical signs and symptoms is variable and complete heart block with need for therapy is rare. The combination of the increased prevalence of structural cardiovascular disease and the direct impact of inflammatory mechanisms on cardiac electrophysiology seems to be responsible for the higher rate of tachyarrhythmias. In particular, fibroblast activation, gap junction impairment via changes in connexin composition and abnormalities in intracellular calcium-handling are mentioned. Electrocardiographic markers of an increased arrhythmogenic potential in patients with chronic autoimmune disorders may include prolonged P‑wave duration as well as abnormal QTc interval and reduced heart rate variability. Thus, minimizing the inflammatory burden through tight control of disease activity may help reduce the arrhythmic load.

Heart rate variability and inflammatory markers in neonates with hypoxic-ischemic encephalopathy

To examine heart rate variability (HRV) and inflammatory markers as predictors for neurological injury in neonates undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy (HIE). We hypothesized that HRV would differentiate between infants with no/mild injury and infants with moderate/severe injury observed on MRI. Because HRV can be associated with the inflammatory cascade, cytokine concentrations were compared with the severity of brain injury indicated by MRI. Further, we studied the effect of temperature, sex, and mechanical ventilation on HRV. HRV was prospectively collected on neonates with HIE using spectral analysis for low and high frequency components (n = 16). A subset (n = 10) of neonates had serum available for inflammatory cytokine analysis obtained during cooling. Neonates were stratified into no/mild or moderate/severe injury based on MRI obtained after rewarming. Differences in HRV were identified; lower low frequency power predicted more injury on MRI. Additionally, in neonates with HIE after cooling procedure, HRV differed by gender. Elevated RANTES (CCL5) and decreased GM-CSF (Granulocyte-macrophage colony-stimulating factor) at 96 hours predicted less severe injury. In this small study, HRV differs between no/mild and moderate/severe injury in neonates with HIE. With further study, this may aid the clinician in real-time decision making. HRV differs by gender. Finally, inflammatory biomarkers may help elucidate the pathophysiology of HIE.

[Heart Rate Variability - State of Research and Clinical Applicability]

Heart Rate Variability - State of Research and Clinical Applicability Abstract. Heart rate variability is considered a marker of autonomous nervous system activity. Autonomic imbalance is found as a common component in a wide range of pathologies. It has been found to precede the onset of pathologic states and correlates with therapy response. In addition, heart rate variability at rest is a psychophysiological phenomenon with broad significance. Psychological experience affects physiological homeostasis, including immune processes, via the autonomous nerve system, which biologically underpins psychosomatic effects and makes them measurable by heart rate variability. The autonomous nerve system as the interface of this psychophysiological regulation is becoming increasingly important in heart rate variability research and allows a better understanding of the interactions between psyche, lifestyle, autonomous regulation and chronic illness. It requires a systemic, cross-organ view as well as an orientation towards long-term processes. The assessment and normalization of autonomic imbalance thus represents a novel therapeutic strategy from which numerous interventions and lifestyle modifications can be derived. Interventions that strengthen the vagal tone (aerobic or moderate physical training, relaxation techniques, vagus nerve stimulation, etc.) are becoming increasingly important. Despite the simple non-invasive measurement and popularity as a research instrument, interpretation is complex, and clinical implementation has been reluctant so far. Nevertheless, guidelines and data sets of reference values exist for users to apply.

From Individual Output to Pooled Data

Abstract. This technical note introduces an easy-to-use macro in Office Excel to batch the output from Kubios HRV 2.2, which is a software program for heart rate variability (HRV) data extraction. Due to a new release of the program, previous solutions have become outdated. The current macro simplifies and substantially reduces the time needed to post-process the output from Kubios HRV 2.2. With the use of this macro, advancements in knowledge on the role of HRV in mental and physical health can be accelerated.

Autoinflammatory and autoimmune contributions to complex regional pain syndrome

Complex regional pain syndrome (CRPS) is a highly enigmatic syndrome typically developing after injury or surgery to a limb. Severe pain and disability are common among those with chronic forms of this condition. Accumulating evidence suggests that CRPS may involve both autoinflammatory and autoimmune components. In this review article, evidence for dysfunction of both the innate and adaptive immune systems in CRPS is presented. Findings from human studies in which cytokines and other inflammatory mediators were measured in the skin of affected limbs are discussed. Additional results from studies of mediator levels in animal models are evaluated in this context. Similarly, the evidence from human, animal, and translational studies of the production of autoantibodies and the potential targets of those antibodies is reviewed. Compelling evidence of autoinflammation in skin and muscle of the affected limb has been collected from CRPS patients and laboratory animals. Cytokines including IL-1β, IL-6, TNFα, and others are reliably identified during the acute phases of the syndrome. More recently, autoimmune contributions have been suggested by the discovery of self-directed pain-promoting IgG and IgM antibodies in CRPS patients and model animals. Both the autoimmune and the autoinflammatory components of CRPS appear to be regulated by neuropeptide-containing peripheral nerve fibers and the sympathetic nervous system. While CRPS displays a complex neuroimmunological pathogenesis, therapeutic interventions could be designed targeting autoinflammation, autoimmunity, or the neural support for these phenomena.

Heart rate variability testing: could it change spending for rheumatoid arthritis patients in the United States? An exploratory economic analysis

BACKGROUND

Autonomic nervous system (ANS) testing with heart rate variability (HRV) has been shown in early research to predict 52-week outcomes in rheumatoid arthritis (RA). HRV testing could be combined with putative ANS biologic pathways to improve treatment response for RA patients. This study explored potential costs and health outcomes of introducing HRV testing into RA treatment, without and with ANS optimization.

METHODS

A decision tree exploratory economic model compared HRV testing to standard care in moderate-to-severe biologic-eligible patients over a 10-year time horizon. HRV data was derived from an observational study of RA patients (n = 33). Patients were stratified into treatment groups based on HRV test scores indicating "low probability of response" and "moderate to high probability of response". This study explored adding ANS optimization based on HRV score followed by clinically-appropriate treatment. Costs and quality-adjusted life-years (QALYs) for the US population were estimated.

RESULTS

HRV testing in biologic-eligible patients decreased non-effective biologic use, reducing US healthcare costs by $34.6 billion over 10 years with QALYs unchanged. When combined with ANS optimization in biologic-eligible patients, HRV testing could increase costs by $3.6 billion over 10 years but save over 350,000 QALYs. Among all RA patients, HRV testing with ANS optimization could save over $8 billion and over 100,000 QALYs over 10 years, depending on the positive predictive value (PPV) of the HRV test.

CONCLUSIONS

The potential economic impact of introducing HRV testing and ANS optimization into RA treatment appears substantial and cost-effective based on the exploratory analysis. Additional rigorous studies are warranted in larger patient samples to better inform decision-making.