Autonomic Nervous System Dysfunction in Primary Sjögren's Syndrome

2023 EULAR recommendations for the management of fatigue in people with inflammatory rheumatic and musculoskeletal diseases

OBJECTIVES

Fatigue is prevalent in people with inflammatory rheumatic and musculoskeletal diseases (I-RMDs) and recognised as one of the most challenging symptoms to manage. The existence of multiple factors associated with driving and maintaining fatigue, and the evidence about what improves fatigue has led to a multifaceted approach to its management. However, there are no recommendations for fatigue management in people with I-RMDs. This lack of guidance is challenging for those living with fatigue and health professionals delivering clinical care. Therefore, our aim was to develop EULAR recommendations for the management of fatigue in people with I-RMDs.

METHODS

A multidisciplinary taskforce comprising 26 members from 14 European countries was convened, and two systematic reviews were conducted. The taskforce developed the recommendations based on the systematic review of evidence supplemented with taskforce members' experience of fatigue in I-RMDs.

RESULTS

Four overarching principles (OAPs) and four recommendations were developed. OAPs include health professionals' awareness that fatigue encompasses multiple biological, psychological and social factors which should inform clinical care. Fatigue should be monitored and assessed, and people with I-RMDs should be offered management options. Recommendations include offering tailored physical activity and/or tailored psychoeducational interventions and/or, if clinically indicated, immunomodulatory treatment initiation or change. Patient-centred fatigue management should consider the individual's needs and preferences, their clinical disease activity, comorbidities and other psychosocial and contextual factors through shared decision-making.

CONCLUSIONS

These 2023 EULAR recommendations provide consensus and up-to-date guidance on fatigue management in people with I-RMDs.

Amyotrophic lateral sclerosis associated with Sjögren's syndrome: a case report

BACKGROUND

Motor neuron disease (MND) is a chronic and progressive neurodegenerative disorder with an unknown cause. The development of amyotrophic lateral sclerosis (ALS) is believed to be linked to an immune response. Monocytes/macrophages and T cells are key players in the disease's advancement. Monitoring levels of cytokines in the blood can help forecast patient outcomes, while immunotherapy shows promise in alleviating symptoms for certain individuals.

CASE PRESENTATION

A 56-year-old male patient was admitted to the hospital due to progressive limb weakness persisting for eight months. The neurological examination revealed impairments in both upper and lower motor neurons, as well as sensory anomalies, without corresponding signs. Electrophysiological examination results indicated extensive neuronal damage and multiple peripheral nerve impairments, thereby the diagnosis was ALS. One month ago, the patient began experiencing symptoms of dry mouth and a bitter taste. Following tests for rheumatic immune-related antibodies and a lip gland biopsy, a diagnosis of Sjögren's syndrome (SS) was proposed. Despite treatment with medications such as hormones (methylprednisolone), immunosuppressants (hydroxychloroquine sulfate), and riluzole, the symptoms did not significantly improve, but also did not worsen.

CONCLUSION

It is recommended to include screening for SS in the standard assessment of ALS. Furthermore, research should focus on understanding the immune mechanisms involved in ALS, providing new insights for the diagnosis and treatment of ALS in conjunction with SS.

Neurological and Psychiatric Clinical Manifestations of Sjögren Syndrome

PURPOSE OF REVIEW

Sjögren Syndrome is a systemic autoimmune disorder that presents mainly with sicca symptoms, but frequently affects other body systems which can lead to a wide variety of manifestations. Understanding the neurological and psychiatric manifestations of Sjögren Syndrome can help with an earlier diagnosis of this disease and leads to better clinical outcomes.

RECENT FINDINGS

We provide an updated overview of the central neurological manifestations, peripheral neurological manifestations and psychiatric manifestations and their diagnosis when associated with primary Sjögren Syndrome. The epidemiology and clinical features of the neurological and psychiatric manifestations are derived from different cohort studies and review articles that were selected from PubMed searches conducted between January 2024 and March 2024. The absence of diagnostic criteria and the scarcity of large, robust studies makes the recognition of the neurological and psychiatric manifestations of Sjögren Syndrome more difficult. Maintaining a high index of suspicion in clinical practice and a close collaboration between the Neurologist and the Rheumatologist will facilitate the diagnosis and management of these patients.

Spirituality is associated with immune parameters and disease activity in primary Sjögren's syndrome: a cross-sectional study

The role of spirituality in health and disease is a complex and emerging area of research. Incorporating spirituality into the bio-psycho-social model of health and disease leading to the bio-psycho-social-spiritual model provides a more comprehensive framework. In this context, chronic disorders like primary Sjögren's syndrome (pSS) are of interest due to their intricate interactions between biological, psychological, and spiritual factors. This study explored the relationship between spirituality, immune parameters, and disease activity in pSS patients. Data from 108 patients were analyzed, including self-assessed spirituality (answering to direct questions and completing the Spiritual Transcendence Scale), immunological parameters and disease activity scores. The findings revealed several associations. Individuals with spiritual attitudes or engaged in regular prayer/meditation showed lower serum levels of autoantibodies specific to pSS and lower disease activity scores. Spiritual engagement was also linked to decreased perceived skin and tracheal dryness, suggesting potential benefits for physical symptoms. These findings suggest that spirituality may play a significant role in modulating immune responses and disease activity in pSS patients. The study underscores the importance of considering spirituality as an integral part of the holistic approach to health and disease, further expanding the understanding of the interconnectedness of biological, psychological, and spiritual dimensions.

Parasympathetic neurons derived from human pluripotent stem cells model human diseases and development

Autonomic parasympathetic neurons (parasymNs) control unconscious body responses, including "rest-and-digest." ParasymN innervation is important for organ development, and parasymN dysfunction is a hallmark of autonomic neuropathy. However, parasymN function and dysfunction in humans are vastly understudied due to the lack of a model system. Human pluripotent stem cell (hPSC)-derived neurons can fill this void as a versatile platform. Here, we developed a differentiation paradigm detailing the derivation of functional human parasymNs from Schwann cell progenitors. We employ these neurons (1) to assess human autonomic nervous system (ANS) development, (2) to model neuropathy in the genetic disorder familial dysautonomia (FD), (3) to show parasymN dysfunction during SARS-CoV-2 infection, (4) to model the autoimmune disease Sjögren's syndrome (SS), and (5) to show that parasymNs innervate white adipocytes (WATs) during development and promote WAT maturation. Our model system could become instrumental for future disease modeling and drug discovery studies, as well as for human developmental studies.

Unveiling the age-related dynamics in Sjögren's syndrome: Insights from heart rate variability and autonomic function

BACKGROUND

Sjögren's Syndrome (SS), mainly affecting women in their midlife, is characterized by persistent inflammation in glands producing tears and saliva, often leading to significant complications. This study investigates the differences in autonomic system functioning between individuals with SS and healthy controls.

METHODS

From April 2019 to December 2022, 329 diagnosed primary SS (pSS) patients and 30 healthy controls were enrolled at Taipei Veterans General Hospital, Taipei, Taiwan. The study assessed autonomic nervous system functioning using various HRV metrics. Participants were divided based on age and AECG criteria, including salivary gland biopsy and autoantibody status.

RESULTS

Significant differences in Heart Rate Variability (HRV) were observed between pSS patients and healthy controls. The total power index was notably lower in pSS patients (4.98 ± 1.29) than in controls (5.54 ± 1.21, p = .022). Additionally, Vagal (VAG) activity was significantly reduced in the pSS group (4.95 ± 1.33) compared to the healthy control group (5.47 ± 1.19, p = .041). Age-stratified analysis highlighted that the ≤50 years pSS group had a higher heart rate (77.74 ± 10.42) compared to the >50 years group (73.86 ± 10.35, p = .005). This group also showed a higher total power index (5.78 ± 1.30) versus the >50 years group (4.68 ± 1.19, p < .001), and significantly lower VAG activity (4.70 ± 1.26, p = .007) compared to healthy controls. Furthermore, the Standard Deviation of Normal-to-Normal Intervals (SDNN) was greater in the ≤50 years SS group (44.45 ± 37.12) than in the >50 years group (33.51 ± 26.18, p = .007). In pSS patients, those positive for both salivary gland biopsy and autoantibodies demonstrated a lower Total Power (4.25 ± 1.32) and R-wave validity (93.50 ± 4.79, p < .05) than other groups, suggesting more severe autonomic imbalance. The R-R interval variation (RRIV) was also significantly higher in this dual-positive group (696.10 ± 975.41, p < .05). Additionally, the ESSPRI for dryness was markedly higher in the dual-positive group (8.10 ± 1.45, p < .05), indicating more severe symptoms. These findings reveal significant variations in autonomic function in SS patients, especially in those with dual-positive biopsy and autoantibody status.

CONCLUSION

This study demonstrates significant autonomic dysfunction in pSS patients compared to healthy controls, particularly in those positive for both salivary gland biopsy and autoantibodies. The age-stratified analysis further emphasizes the impact of aging on autonomic system functioning in pSS, suggesting a need for age-specific management approaches in pSS patient care.

Autoimmune Autonomic Neuropathy: From Pathogenesis to Diagnosis

Autoimmune autonomic ganglionopathy (AAG) is a disease of autonomic failure caused by ganglionic acetylcholine receptor (gAChR) autoantibodies. Although the detection of autoantibodies is important for distinguishing the disease from other neuropathies that present with autonomic dysfunction, other factors are important for accurate diagnosis. Here, we provide a comprehensive review of the clinical features of AAG, highlighting differences in clinical course, clinical presentation, and laboratory findings from other neuropathies presenting with autonomic symptoms. The first step in diagnosing AAG is careful history taking, which should reveal whether the mode of onset is acute or chronic, followed by an examination of the time course of disease progression, including the presentation of autonomic and extra-autonomic symptoms. AAG is a neuropathy that should be differentiated from other neuropathies when the patient presents with autonomic dysfunction. Immune-mediated neuropathies, such as acute autonomic sensory neuropathy, are sometimes difficult to differentiate, and therefore, differences in clinical and laboratory findings should be well understood. Other non-neuropathic conditions, such as postural orthostatic tachycardia syndrome, chronic fatigue syndrome, and long COVID, also present with symptoms similar to those of AAG. Although often challenging, efforts should be made to differentiate among the disease candidates.

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.

Vagus nerve stimulation as a therapeutic option in inflammatory rheumatic diseases

The vagus nerve forms intricate neural connections with an extensive number of organs, particularly the digestive system. The vagus nerve has a pivotal role as a fundamental component of the autonomic nervous system, exhibiting an essential effect. It establishes a direct link with the parasympathetic system, consequently eliciting the synaptic release of acetylcholine. Recent studies have revealed the potential anti-inflammatory function of the vagus nerve. The activation of the hypothalamic system through the stimulation of vagal afferents is fundamentally involved in regulating inflammation. This activation process leads to the production of cortisol. The other mechanism, defined as the cholinergic anti-inflammatory pathway, is characterized by the involvement of vagal efferents. These fibers release the neurotransmitter acetylcholine at particular synaptic connections, involving interactions with macrophages and enteric neurons. The mechanism under consideration is ascribed to the α-7-nicotinic acetylcholine receptors. The fusion of acetylcholine receptors is responsible for the restricted secretion of inflammatory mediators by macrophages. A potential mechanism for anti-inflammatory effects involves the stimulation of the sympathetic system through the vagus nerve, leading to the control of immunological responses within the spleen. This article offers an extensive summary of the present knowledge regarding the therapeutic effectiveness of stimulating the vagus nerve in managing inflammatory rheumatic conditions based on the relationship of inflammation with the vagus nerve. Furthermore, the objective is to present alternatives that may be preferred while applying vagus nerve stimulation approaches.

Primary Sjogren's syndrome presenting as an isolated severe autonomic dysfunction treated with steroids

Primary Sjogren's syndrome (pSS) is an autoimmune connective tissue disorder with multisystem manifestations. We here report a previously healthy woman who presented with autonomic dysfunction in the form of severe dizziness without any apparent sensory neuropathy. Detailed history and examination revealed the signs and symptoms of Sjogren's syndrome such as constipation and dry eyes and mouth, following which anti-SSA and SSB antibodies were found to be positive. Finally, a diagnosis of pSS was established after ruling out all the other causes of autonomic dysfunction in addition to the clinical and laboratory evidence. The patient was treated with the maximum doses of midodrine and fludrocortisone, yet no progress was noticed. Hence, a trial of steroids was started and she showed a significant clinical improvement. Our patient presented with pure autonomic failure associated with Sjogren's syndrome, making it an extremely rare entity.

Effects of low-level laser therapy on burning pain and quality of life in patients with burning mouth syndrome: a systematic review and meta-analysis

BACKGROUND

Burning mouth syndrome (BMS) is a complex chronic pain disorder that significantly impairs patients' quality of life. Low-level laser therapy (LLLT) uses infrared or near-infrared light to produce analgesic, anti-inflammatory, and biological stimulation effects. The aim of this systematic review is to evaluate the effect of LLLT on burning pain, quality of life, and negative emotions in patients with BMS.

METHODS

The PubMed, Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane Library, Web of Science, and Scopus databases were searched up January 2023 to identify relevant articles. All randomized controlled trials that were published in English and examined the use of LLLT treatment for BMS were included. The methodological quality of the included trials was assessed using the Cochrane risk of bias tool for randomized controlled trials (RCTs). A meta-analysis was performed to evaluate burning pain, quality of life, and negative emotions. Sensitivity, subgroup, and funnel plot analyses were also carried out.

RESULTS

Fourteen RCTs involving a total of 550 patients with BMS met the inclusion criteria. The results showed that LLLT (measured by the Visual Analog Scale; SMD: -0.87, 95% CI: -1.29 to -0.45, P < 0.001) was more effective for reducing burning pain than placebo LLLT or clonazepam. LLLT improved quality of life (evaluated by the Oral Health Impact Profile-14; SMD: 0.01, 95% CI: -0.58 to 0.60, P = 0.97) and negative emotions (evaluated by the Hospital Anxiety and Depression Scale; SMD: -0.12, 95% CI: -0.54 to 0.30, P = 0.59), but these effects were not statistically significant.

CONCLUSIONS

The meta-analysis revealed that LLLT may be an effective therapy for improving burning pain in patients with BMS, and producing a positive influence on quality of life and negative emotions. A long-term course of intervention, a larger sample size, and a multidisciplinary intervention design are urgently needed in future research.

TRIAL REGISTRATION

PROSPERO registration number: CRD42022308770.

Characterizing Sjögren-Associated Fatigue: A Distinct Phenotype from ME/CFS

Fatigue is the most commonly reported and debilitating extraglandular symptom of primary Sjögren's syndrome (pSS). Fatigue and exertional intolerance are hallmark symptoms of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). We aimed to characterize fatigue and further symptoms among pSS patients and to determine whether there is a symptom overlap in pSS and ME/CFS. In 19 patients with pSS, we assessed pSS symptom severity and disease activity via questionnaires as well as the Canadian Consensus Criteria (CCC) for ME/CFS. Hand grip strength (HGS) and levels of α1-, α2-, β1-, β2-, M3- and M4-receptor-autoantibodies were measured. A subgroup of pSS patients exhibited severe fatigue and had higher severity of pain (p = 0.045), depression (p = 0.021) and sleep disturbances (p = 0.020) compared to those with less fatigue. Four of eighteen pSS patients fulfilled the CCC. HGS parameters strongly correlated with fatigue severity (p < 0.05), but strength fully recovered one hour after exertion in contrast to ME/CFS. Levels of β1-, β2- and M4-receptor-autoantibodies were elevated and correlated significantly with disease activity assessed by the ESSDAI (p < 0.05), but not fatigue severity. Only a minor subgroup of pSS patients fulfills the CCC, and post exertional malaise (PEM) is atypical, as it is primarily triggered by mental/emotional but not physical exertion. HGS assessment is an objective measure to assess overall fatigue severity.

[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 Spectrum of Extraglandular Manifestations in Primary Sjögren's Syndrome

Extraglandular manifestations (EGMs) in primary Sjogren's syndrome (pSS) represent the clinical expression of the systemic involvement in this disease. EGMs are characterized by a wide heterogeneity; virtually any organ or system can be affected, with various degrees of dysfunction. The existing gaps of knowledge in this complex domain of extraglandular extension in pSS need to be overcome in order to increase the diagnostic accuracy of EGMs in pSS. The timely identification of EGMs, as early as from subclinical stages, can be facilitated using highly specific biomarkers, thus preventing decompensated disease and severe complications. To date, there is no general consensus on the diagnostic criteria for the wide range of extraglandular involvement in pSS, which associates important underdiagnosing of EGMs, subsequent undertreatment and progression to severe organ dysfunction in these patients. This review article presents the most recent basic and clinical science research conducted to investigate pathogenic mechanisms leading to EGMs in pSS patients. In addition, it presents the current diagnostic and treatment recommendations and the trends for future therapeutic strategies based on personalized treatment, as well as the latest research in the field of diagnostic and prognostic biomarkers for extraglandular involvement in pSS.

Depression in Sjögren's syndrome mediates the relationship between pain, fatigue, sleepiness, and overall quality of life

Objectives

Sjögren's syndrome (SS) includes many extra-glandular symptoms such as fatigue, pain, sleepiness and depression, which impact on quality of life (QoL). These symptoms also influence each other and could be linked by autonomic nervous system (ANS) dysregulation. Our aim was to model the role of putative predictive variables, including depression in the relationships between ANS function, fatigue, and QoL in SS.

Methods

Cross-sectional analysis of self-reported data from the multicentre UK primary SS registry. The Composite Autonomic Symptom Scale (COMPASS) was used to assess autonomic function, the Hospital Anxiety and Depression Scale (HADS) to assess anxiety and depression and the EuroQol-5 Dimension (EQ-5D) to assess QoL. Validated scales were used for other clinical variables. Using multiple regression analysis and structural equation modelling (SEM), we investigated how the QoL of people with SS is impacted by the direct and indirect effects of fatigue, sleepiness, depression, symptom burden and ANS function, and their interactions.

Results

Data was obtained for 1046 people with SS, 56% COMPASS completers. Symptoms of ANS dysregulation were common. Participants with ANS dysregulation had more severe depression, anxiety, dryness, fatigue, pain, sleepiness and QoL (P < 0.01 for all). Depression, anxiety, dryness, and pain were independent predictors of ANS function in the multiple regression model (P < 0.05 for all). ANS function could not be included in the SEM. The SEM model had good fit to the data (comparative fit index = 0.998) and showed that, in people with SS, depression mediates the effects of pain, fatigue and sleepiness on QoL.

Conclusion

Our results show that diagnosing and treating depression in people with SS could have direct positive impact on QoL, and significantly ameliorate the impact of fatigue and pain.

Neural dysregulation in post-COVID fatigue

Following infection with SARS-CoV-2, a substantial minority of people develop lingering after-effects known as 'long COVID'. Fatigue is a common complaint with a substantial impact on daily life, but the neural mechanisms behind post-COVID fatigue remain unclear. We recruited 37 volunteers with self-reported fatigue after a mild COVID infection and carried out a battery of behavioural and neurophysiological tests assessing the central, peripheral and autonomic nervous systems. In comparison with age- and sex-matched volunteers without fatigue (n = 52), we show underactivity in specific cortical circuits, dysregulation of autonomic function and myopathic change in skeletal muscle. Cluster analysis revealed no subgroupings, suggesting post-COVID fatigue is a single entity with individual variation, rather than a small number of distinct syndromes. Based on our analysis, we were also able to exclude dysregulation in sensory feedback circuits and descending neuromodulatory control. These abnormalities on objective tests may aid in the development of novel approaches for disease monitoring.

Atypical posterior reversible encephalopathy syndrome associated with Sjögren'‍s syndrome: a case report

Sjögren'‍s syndrome (SJS) is a common autoimmune disease. Generally, posterior reversible encephalopathy syndrome (PRES) is often concomitant with autoimmune disease; however, PRES rarely complicates SJS. Thus, the detailed clinical course of cases with SJS and PRES remains unknown. We present the case of a 71-year-old female patient with primary SJS, whose magnetic resonance (MR) images showed bilateral vasogenic edema in the basal ganglia, brainstem, and cerebellum. Cerebrospinal fluid (CSF) examination revealed increased IgG index and higher interleukin-6 and anti-SSA-autoantibody levels. Management of her blood pressure combined with corticosteroid therapy improved her neurological symptoms, including abnormal CSF and MR imaging findings.

Prevalence and characteristics of dry eye disease in Parkinson's disease: a systematic review and meta-analysis

We investigated and characterized the prevalence of dry eye disease (DED) in Parkinson's disease (PD). PubMed and EMBASE databases were searched for relevant studies between January 1, 1979 and March 10, 2022. Quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist. Study-specific estimates were combined using the DerSimonian-Laird random-effects model. Prevalence of subjective DED symptoms in patients with PD and mean differences in blink rate, corneal thickness, tear film breakup time, and tear secretion volume on Schirmer test I were compared to those in controls. Of 383 studies, 13 (1519 patients with PD) and 12 were included in qualitative and quantitative syntheses, respectively. Meta-analysis revealed a 61.1% prevalence of subjective DED symptoms in PD and that, compared with controls, patients with PD had significantly lower blink rate, thinner corneal thickness, shorter tear film breakup time, and lower tear secretion volumes on Schirmer test I, without and with anesthesia.

Cardiovascular Disease in Primary Sjögren's Syndrome: Raising Clinicians' Awareness

In the ever evolving landscape of systemic immune mediated diseases, an increased awareness regarding the associated cardiovascular system impairment has been noted in recent years. Even though primary Sjögren's Syndrome (pSS) is one of the most frequent autoimmune diseases affecting middle-aged individuals, the cardiovascular profile of this specific population is far less studied, at least compared to other autoimmune diseases. Traditional cardiovascular risk factors and disease specific risk factors are inextricably intertwined in this particular case. Therefore, the cardiovascular risk profile in pSS is a multifaceted issue, sometimes difficult to assess. Furthermore, in the era of multimodality imaging, the diagnosis of subclinical myocardial and vascular damage is possible, with recent data pointing that the prevalence of such involvement is higher in pSS than in the general population. Nevertheless, when approaching patients with pSS in terms of cardiovascular diseases, clinicians are often faced with the difficult task of translating data from the literature into their everyday practice. The present review aims to synthesize the existing evidence on pSS associated cardiovascular changes in a clinically relevant manner.