Effects of 12-week aerobic exercise on patient-reported outcomes in women with systemic lupus erythematosus

ActiLup: is it feasible? High-intensity interval training in systemic lupus erythematosus patients with fatigue: protocol for a prospective, monocentric proof-of-concept study

The symptoms of active systemic lupus erythematosus (SLE) potentially lead to inactivity, muscle loss and social isolation. In addition to medical treatment, the current EULAR recommendations describe the relevance of physical activity, exercise and training as a non-pharmacological management option in patients with SLE. A positive interaction between fatigue and the basic health-promoting effects of exercise is well established. Still unclear is what kind of training, setting, and intensity show optimal objective and subjective outcomes. The study will include 40 adult SLE patients with moderate to severe fatigue. The study lasts 28 weeks and is divided into a 12-week "real-world" monitoring phase before rehabilitation, a 4-week inpatient rehabilitation phase, and a 12-week maintenance activity and training phase after the rehabilitation. The parameters consisted of physical performance parameters, laboratory parameters, physician and patient-related questionnaires and activity data based on a fitness watch. During rehabilitation, patients receive individual high-intensity interval training (HIIT), basic endurance training and functional interval training. This proof-of-concept trial aims to investigate if high-intensity interval training is feasible and how VO2peak is increased. Additionally, the effect of the severity of fatigue measured by patient-related outcomes and the number of anti-NR2 antibodies is focussed. This study was approved by the Ethics Committee of the Medical Association of Rhineland-Palatinate and complies with the standards of the Declaration of Helsinki. All participants will sign a written informed consent. Trial registration number: DRKS00022933.

Physical inactivity exacerbates pathologic inflammatory signalling at the single cell level in patients with systemic lupus

BACKGROUND

Physical activity is an adjunctive therapy that improves symptoms in people living with systemic lupus erythematosus (SLE), yet the mechanisms underlying this benefit remain unclear.

METHODS

We carried out a cohort study of 123 patients with SLE enrolled in the California Lupus Epidemiology Study (CLUES). The primary predictor variable was self-reported physical activity, which was measured using a previously validated instrument. We analyzed peripheral blood mononuclear cell (PBMC) single-cell RNA sequencing (scRNA-seq) data available from the cohort. From the scRNA-seq data, we compared immune cell frequencies, cell-specific gene expression, biological signalling pathways, and upstream cytokine activation states between physically active and inactive patients, adjusting for age, sex and race.

FINDINGS

We found that physical activity influenced immune cell frequencies, with sedentary patients most notably demonstrating greater CD4+ T cell lymphopenia (Padj = 0.028). Differential gene expression analysis identified a transcriptional signature of physical inactivity across five cell types. In CD4+ and CD8+ T cells, this signature was characterized by 686 and 445 differentially expressed genes (Padj < 0.1). Gene set enrichment analysis demonstrated enrichment of proinflammatory genes in the TNF-α signalling through NF-kB, interferon-γ (IFN-γ), IL2/STAT5, and IL6/JAK/STAT3 signalling pathways. Computational prediction of upstream cytokine activation states suggested CD4+ T cells from physically inactive patients exhibited increased activation of TNF-α, IFN-γ, IL1Β, and other proinflammatory cytokines. Network analysis demonstrated interconnectivity of genes driving the proinflammatory state of sedentary patients. Findings were consistent in sensitivity analyses adjusting for corticosteroid treatment and physical function.

INTERPRETATION

Taken together, our findings suggest a mechanistic explanation for the observed benefits of physical activity in patients with SLE. Specifically, we find that physical inactivity is associated with altered frequencies and transcriptional profiles of immune cell populations and may exacerbate pathologic inflammatory signalling via CD4+ and CD8+ T cells.

FUNDING

This work was supported by the US National Institutes of Health (NIH) (R01 AR069616, K23HL138461-01A1, K23AT011768) the US CDC (U01DP0670), and the CZ Biohub.

Clinical Practice Mexican Guidelines for the Treatment of Systemic Lupus Erythematosus: 2024 Update

Herein we present the update for the Mexican Guidelines for the Treatment of Systemic Lupus Erythematosus. It involves the participation of several experts along the country, following the GRADE system. We included aspects regarding vaccines, pregnancy and cardiovascular risk which were not presented in the previous guidelines in 2017.

Sleep Disorders in Connective Tissue Diseases-Coexisting Diseases or Disease Components?

This comprehensive review examines the complex relationship between sleep disorders and rheumatic diseases, supported by findings from the latest research articles. It encompasses various rheumatic conditions, including rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis. The review reveals the bidirectional relationship between sleep disorders and these diseases, emphasizing their impact on disease progression and quality of life. Conventional and alternative therapeutic interventions for connective tissue diseases are presented, focusing on improving sleep quality and alleviating rheumatic symptoms. The role of pro-inflammatory cytokines and their potential modulation through pharmacological agents is also discussed. In the treatment of sleep disorders, various options are proposed, such as cognitive behavioral therapy for insomnia, physical activity, dietary modifications, and alternative approaches like reflexology and acupuncture. Thus, this review offers a nuanced understanding of the connection between sleep disorders and rheumatic diseases, supported by evidence from diverse studies. Such an approach is particularly important because it enhances sleep quality for overall patient well-being in the holistic management of rheumatic conditions.

Efficacy of lifestyle interventions in the management of systemic lupus erythematosus: a systematic review of the literature

We performed a systematic review to explore existing evidence regarding the efficacy of lifestyle interventions for the management of systemic lupus erythematosus (SLE). The search was conducted on the 22nd of June 2021 for publications between 1st of January 2000 and the date of search. Additional articles within the aforementioned timeframe and until December 2023 were added by hand searching. Databases utilized were Medline, Embase, Web of Science, and Cinahl. Lifestyle interventions were defined as any intervention encompassing one or more of the following: physical exercise, diet and nutrition, mental health, harmful exposures, sleep, and social relations. The Joanna Briggs Institute critical appraisal tools were used for risk of bias assessment. The search yielded 11,274 unique records, we assessed the full text of 199 records, and finally included 102 studies. Overall, the quality of the evidence is limited, and there were multiple sources of heterogeneity. The two domains most extensively researched were mental health (40 records) and physical exercise (39 records). Psychological interventions had a positive effect on depressive symptoms, anxiety, and health-related quality of life (HRQoL), whereas physical exercise improved fatigue, depressive symptoms, aerobic capacity, and physical functioning. Studies on diet and nutrition (15 records) support that low fat intake and Mediterranean diet may be beneficial for reducing cardiovascular risk, but large interventional studies are lacking. Studies on harmful exposures (7 records) support photoprotection and use of sunscreen. While studies imply benefits regarding disease burden and drug efficacy in non-smokers and regarding HRQoL in normal-weight patients, more survey is needed on tobacco smoking and alcohol consumption, as well as weight control strategies. Studies on social relations (1 record) and sleep (no records) were sparse or non-existent. In conclusion, psychosocial interventions are viable for managing depressive symptoms, and exercise appears essential for reducing fatigue and improving aerobic capacity and physical function. Photoprotection should be recommended to all patients. Lifestyle interventions should be considered a complement, not a substitute, to pharmacotherapy.

Recommendations for physical activity and exercise in persons living with Systemic Lupus Erythematosus (SLE): consensus by an international task force

OBJECTIVE

This international task force aimed to provide healthcare professionals and persons living with systemic lupus erythematosus (SLE) with consensus-based recommendations for physical activity and exercise in SLE.

METHODS

Based on evidence from a systematic literature review and expert opinion, 3 overarching principles and 15 recommendations were agreed on by Delphi consensus.

RESULTS

The overarching principles highlight the importance of shared decision-making and the need to explain the benefits of physical activity to persons living with SLE and other healthcare providers. The 15 specific recommendations state that physical activity is generally recommended for all people with SLE, but in some instances, a medical evaluation may be needed to rule out contraindications. Pertaining to outdoor activity, photoprotection is necessary. Both aerobic and resistance training programmes are recommended, with a gradual increase in frequency and intensity, which should be adapted for each individual, and ideally supervised by qualified professionals.

CONCLUSION

In summary, the consensus reached by the international task force provides a valuable framework for the integration of physical activity and exercise into the management of SLE, offering a tailored evidence-based and eminence-based approach to enhance the well-being of individuals living with this challenging autoimmune condition.

Exercise as adjunctive therapy for systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is a rare, chronic autoimmune inflammatory disease with a prevalence varying from 4.3 to 150 people in 100,000, or approximately five million people worldwide. Systemic manifestations frequently include internal organ involvement, a characteristic malar rash on the face, pain in joints and muscles, and profound fatigue. Exercise is purported to be beneficial for people with SLE. For this review, we focused on studies that examined all types of structured exercise as an adjunctive therapy in the management of SLE.

OBJECTIVES

To evaluate the benefits and harms of structured exercise as adjunctive therapy for adults with SLE compared with usual pharmacological care, usual pharmacological care plus placebo and usual pharmacological care plus non-pharmacological care.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 30 March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of exercise as an adjunct to usual pharmacological treatment in SLE compared with placebo, usual pharmacological care alone and another non-pharmacological treatment. Major outcomes were fatigue, functional capacity, disease activity, quality of life, pain, serious adverse events, and withdrawals due to any reason, including any adverse events.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our major outcomes were 1. fatigue, 2. functional capacity, 3. disease activity, 4. quality of life, 5. pain, 6. serious adverse events, and 7. withdrawals due to any reason. Our minor outcomes were 8. responder rate, 9. aerobic fitness, 10. depression, and 11. anxiety. We used GRADE to assess certainty of evidence. The primary comparison was exercise compared with placebo.

MAIN RESULTS

We included 13 studies (540 participants) in this review. Studies compared exercise as an adjunct to usual pharmacological care (antimalarials, immunosuppressants, and oral glucocorticoids) with usual pharmacological care plus placebo (one study); usual pharmacological care (six studies); and another non-pharmacological treatment such as relaxation therapy (seven studies). Most studies had selection bias, and all studies had performance and detection bias. We downgraded the evidence for all comparisons because of a high risk of bias and imprecision. Exercise plus usual pharmacological care versus placebo plus usual pharmacological care Evidence from a single small study (17 participants) that compared whole body vibration exercise to whole body placebo vibration exercise (vibrations switched off) indicated that exercise may have little to no effect on fatigue, functional capacity, and pain (low-certainty evidence). We are uncertain whether exercise results in fewer or more withdrawals (very low-certainty evidence). The study did not report disease activity, quality of life, and serious adverse events. The study measured fatigue using the self-reported Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-Fatigue), scale 0 to 52; lower score means less fatigue. People who did not exercise rated their fatigue at 38 points and those who did exercise rated their fatigue at 33 points (mean difference (MD) 5 points lower, 95% confidence interval (CI) 13.29 lower to 3.29 higher). The study measured functional capacity using the self-reported 36-item Short Form health questionnaire (SF-36) Physical Function domain, scale 0 to 100; higher score means better function. People who did not exercise rated their functional capacity at 70 points and those who did exercise rated their functional capacity at 67.5 points (MD 2.5 points lower, 95% CI 23.78 lower to 18.78 higher). The study measured pain using the SF-36 Pain domain, scale 0 to 100; lower scores mean less pain. People who did not exercise rated their pain at 43 points and those who did exercise rated their pain at 34 points (MD 9 points lower, 95% CI 28.88 lower to 10.88 higher). More participants from the exercise group (3/11, 27%) withdrew from the study than the placebo group (1/10, 10%) (risk ratio (RR) 2.73, 95% CI 0.34 to 22.16). Exercise plus usual pharmacological care versus usual pharmacological care alone The addition of exercise to usual pharmacological care may have little to no effect on fatigue, functional capacity, and disease activity (low-certainty evidence). We are uncertain whether the addition of exercise improves pain (very low-certainty evidence), or results in fewer or more withdrawals (very low-certainty evidence). Serious adverse events and quality of life were not reported. Exercise plus usual care versus another non-pharmacological intervention such as receiving information about the disease or relaxation therapy Compared with education or relaxation therapy, exercise may reduce fatigue slightly (low-certainty evidence), may improve functional capacity (low-certainty evidence), probably results in little to no difference in disease activity (moderate-certainty evidence), and may result in little to no difference in pain (low-certainty evidence). We are uncertain whether exercise results in fewer or more withdrawals (very low-certainty evidence). Quality of life and serious adverse events were not reported.

AUTHORS' CONCLUSIONS

Due to low- to very low-certainty evidence, we are not confident on the benefits of exercise on fatigue, functional capacity, disease activity, and pain, compared with placebo, usual care, or advice and relaxation therapy. Harms data were not well reported.

Autoimmune pre-disease

Approximately 5% of the world-wide population is affected by autoimmune diseases. Overall, autoimmune diseases are still difficult to treat, impose a high burden on patients, and have a significant economic impact. Like other complex diseases, e.g., cancer, autoimmune diseases develop over several years. Decisive steps in the development of autoimmune diseases are (i) the development of autoantigen-specific lymphocytes and (often) autoantibodies and (ii) potentially clinical disease manifestation at a later stage. However, not all healthy individuals with autoantibodies develop disease manifestations. Identifying autoantibody-positive healthy individuals and monitoring and inhibiting their switch to inflammatory autoimmune disease conditions are currently in their infancy. The switch from harmless to inflammatory autoantigen-specific T and B-cell and autoantibody responses seems to be the hallmark for the decisive factor in inflammatory autoimmune disease conditions. Accordingly, biomarkers allowing us to predict this progression would have a significant impact. Several factors, such as genetics and the environment, especially diet, smoking, exposure to pollutants, infections, stress, and shift work, might influence the progression from harmless to inflammatory autoimmune conditions. To inspire research directed at defining and ultimately targeting autoimmune predisease, here, we review published evidence underlying the progression from health to autoimmune predisease and ultimately to clinically manifest inflammatory autoimmune disease, addressing the following 3 questions: (i) what is the current status, (ii) what is missing, (iii) and what are the future perspectives for defining and modulating autoimmune predisease.

Changes in cardiorespiratory function and fatigue following 12 weeks of exercise training in women with systemic lupus erythematosus: a pilot study

OBJECTIVE

In patients with systemic lupus erythematosus (SLE), fatigue is a debilitating symptom with poorly understood pathophysiology. Cardiorespiratory dysfunction has been hypothesised as a contributor to SLE-fatigue. The purpose of this exploratory study was to examine changes in cardiorespiratory function, following an exercise training programme in women with SLE, together with patient reported outcomes and other pathophysiological measures that may underlie SLE-fatigue.

METHODS

Sixteen women with SLE and fatigue (Fatigue Severity Scale (FSS) ≥3) were enrolled in a supervised aerobic exercise training programme of vigorous intensity. The primary outcome was time to reach anaerobic threshold (AT-Time) during a cardiopulmonary exercise test (CPET). Secondary outcomes included changes in the 10-minute walk test (10MWT), FSS scores and the Patient Reported Outcomes Measurement Information System (PROMIS-57) survey. Mitochondrial function was assessed by the oxygen consumption rate (OCR)/extracellular acidification rate (ECAR) metabolic potential ratio.

RESULTS

Following 12 weeks of exercise training, AT-Time increased by 93±82 (mean±SD) s (p<0.001), 10MWT increased by 84±66 m (p<0.001) and peak oxygen uptake (VO₂) increased by 1.4±2.0 mL/kg/min (p=0.013). There were improvements in FSS score (-1.4±1.0, p<0.0001) and in most of the PROMIS-57 domains. The decrease in FSS scores correlated with an increase in the OCR/ECAR ratio (Pearson's correlation r=-0.59, p=0.03). A subset of subjects (9/15) had significant reduction in their Interferon Stimulated Genes (ISG) (p=0.007) accompanied by a significant increase in the OCR/ECAR ratio (p=0.013).

CONCLUSIONS

Cardiorespiratory function was improved in concomitance with reductions in fatigue following a 12-week aerobic exercise programme. The reduction in fatigue scores correlated with improvements in mitochondrial function.

Predictors of stress in patients with Lupus

Background

Stress is common in patients with Systemic Lupus Erythematosus (SLE), and is associated with depression, fatigue, and disease flares. Stress may be modifiable and identifying those at high risk allows clinicians and allied health care professionals to develop a multidisciplinary management plan to direct appropriate resources. This study is aimed at identifying predictors of high stress over time among patients with SLE.

Methods

Longitudinal data from two interviews of the Lupus Outcomes Study 2 years apart from 726 patients with SLE were analyzed for stress, measured using the Perceived Stress Scale (PSS; high-stress PSS ≥6). T-test and Chi-square analyses compared patient characteristics by high-stress status. Logistic regressions were conducted with high stress as the dependent variable. Covariates included demographics, disease features, quality of life (QOL), health care utilization (HCU), and comorbidities. QoL was measured using the SF-36 form (Physical Component Score, PCS; Mental Component Score, MCS) and MOS Cognitive Functioning Scale (CFS). HCU indicated having established care with a rheumatologist, use of an emergency room or hospitalization, and quality of care. P ≤ 0.05 were considered significant.

Results

The mean age of the cohort was 50.6 (12.5) years, 92% were women and 68% were Caucasian. The mean (SD) PSS was 5.3 (3.6), and high stress (PSS >6) was noted in 253 participants. Those with high stress were more frequently below the poverty line and less commonly employed. They had a greater prevalence of comorbidities and HCU; and worse disease severity (activity, flare, damage) and QOL. In regression analyses, high stress (baseline) was associated with younger age, married status, worse QOL, and presence of diabetes. Better QOL (PCS, MCS) independently predicted decreased odds of high stress, while high stress (baseline) predicted high stress (OR 3.16, 95% CI 1.85, 5.37, p < 0.0001) at follow-up, after adjusting for demographics, disease features, HCU, and comorbidities.

Conclusion

Patients with SLE should be routinely screened for QOL and stress during their clinical care, to identify those at risk for poor health outcomes. This information can facilitate multidisciplinary management for those at risk for worse health outcomes.

A glimpse into the future of systemic lupus erythematosus

This viewpoint article on a forecast of clinically meaningful changes in the management of systemic lupus erythematosus (SLE) in the next 10 years is based on a review of the current state of the art. The groundwork has been laid by a robust series of classification criteria and treatment recommendations that have all been published since 2019. Building on this strong foundation, SLE management predictably will take significant steps forward. Assessment for lupus arthritis will presumably include musculoskeletal sonography. Large-scale polyomics studies are likely to unravel more of the central immune mechanisms of the disease. Biomarkers predictive of therapeutic success may enter the field; the type I interferon signature, as a companion for use of anifrolumab, an antibody against the common type I interferon receptor, is one serious candidate. Besides anifrolumab for nonrenal SLE and the new calcineurin inhibitor voclosporin in lupus nephritis, both of which are already approved in the United States and likely to become available in the European Union in 2022, several other approaches are in advanced clinical trials. These include advanced B cell depletion, inhibition of costimulation via CD40 and CD40 ligand (CD40L), and Janus kinase 1 (Jak1) and Tyrosine kinase 2 (Tyk2) inhibition. At the same time, essentially all of our conventional therapeutic armamentarium will continue to be used. The ability of patients to have successful SLE pregnancies, which has become much better in the last decades, should further improve, with approaches including tumor necrosis factor blockade and self-monitoring of fetal heart rates. While we hope that the COVID-19 pandemic will soon be controlled, it has highlighted the risk of severe viral infections in SLE, with increased risk tied to certain therapies. Although there are some data that a cure might be achievable, this likely will remain a challenge beyond 10 years from now.

A prescription for exercise in systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) have increased cardiovascular risk, and fatigue is a major subjective complaint. Sedentary lifestyle has been shown to have negative health impacts in cardiovascular and rheumatic disease, though exercise has not traditionally been incorporated into routine therapy recommendations. Regular exercise in SLE may improve difficult to treat Type 2 symptoms, such as fatigue, depression, stress, and quality of life. Insufficient counseling on exercise by physicians is a notable barrier for SLE patients to engage in physical activity. Aerobic exercise regimens are more commonly studied, and have been shown to improve cardiovascular health in SLE. Exercise may improve some inflammatory markers, though does not definitively affect SLE clinical disease activity. Physical activity should be recommended to improve quality of life and cardiovascular health in patients with SLE. Developing clearer guidelines for exercise regimens in a patient-centered manner is warranted, especially given diverse phenotypes of SLE patients and varying degrees of physical limitations.

Physical Fitness Attenuates the Impact of Higher Body Mass and Adiposity on Inflammation in Women With Systemic Lupus Erythematosus

Aims

Higher body mass and adiposity represent independent contributors to the systemic low-grade inflammatory state often observed in patients with systemic lupus erythematosus (SLE). This study assessed the role of physical fitness in the association of body mass and adiposity with inflammation in women with SLE.

Methods

A total of 77 women with SLE were included in this cross-sectional study. We obtained body mass index, waist-to-height ratio, and body fat percentage as indicators of body mass and adiposity. Inflammation was assessed through Serum levels of C-reactive protein, interleukin 6, and leptin. Cardiorespiratory fitness was assessed with the 6-minute walk test, range of motion with the back-scratch test, and muscular strength with handgrip dynamometry.

Results

Cardiorespiratory fitness attenuated the association of both body mass index and body fat percentage with interleukin 6 (all, P<0.05). Range of motion attenuated the association of body mass index with interleukin 6 (P<0.05) and the association of body fat percentage with C-reactive protein (P<0.05). These interactions indicated that higher fitness was associated with a lower increase in inflammation per unit increase of body mass or adiposity. Muscular strength showed a non-significant trend to attenuate the association of body fat percentage with interleukin 6 (P=0.057) but potentiated the association of body fat percentage with leptin (P<0.05).

Conclusion

These findings suggest that higher levels of cardiorespiratory fitness and range of motion might attenuate the impact of higher body mass and adiposity on inflammation in women with SLE. The role of muscular strength requires further investigation.

Effects of Exercise Intervention on Health-Related Quality of Life in Patients with Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis of Controlled Trials

Exercise and physical activity have been deemed as potentially beneficial for patients with systemic lupus erythematosus (SLE). This study aimed to evaluate the effects of exercise interventions on health-related quality of life in patients with SLE using a systematic review and meta-analysis. Randomized and non-randomized controlled trials published up to July 2021 were examined using the PubMed and Embase databases. Of the 1158 articles retrieved, nine were included for systematic review. Five of them were randomized controlled trials and these were assessed using meta-analysis. Hedges’ g effect size was 0.47; 95% (confidence interval 0.21–0.73; p < 0.001) for the physical health and function aspect of health-related quality of life. None of the other seven domains of the SF-36 showed a significant effect size. However, the latter finding was limited by the small number of available trials. In conclusion, this systematic review and meta-analysis supported that exercise intervention compared to usual care might be able to improve the physical functioning domain of health-related quality of life in patients with SLE. Future high-quality randomized controlled trials that incorporate disease-specific health-related quality of life measures are needed to elucidate the role of exercise on health-related quality of life in patients with SLE.

Heart Rate Variability in Women with Systemic Lupus Erythematosus: Association with Health-Related Parameters and Effects of Aerobic Exercise

Abnormal heart rate variability (HRV) has been observed in patients with systemic lupus erythematosus (SLE). In a combined cross-sectional and interventional study approach, we investigated the association of HRV with inflammation and oxidative stress markers, patient-reported outcomes, and the effect of 12 weeks of aerobic exercise in HRV. Fifty-five women with SLE (mean age 43.5 ± 14.0 years) were assigned to either aerobic exercise (n = 26) or usual care (n = 29) in a non-randomized trial. HRV was assessed using a heart rate monitor during 10 min, inflammatory and oxidative stress markers were obtained, psychological stress (Perceived Stress Scale), sleep quality (Pittsburg Sleep Quality Index), fatigue (Multidimensional Fatigue Inventory), depressive symptoms (Beck Depression Inventory), and quality of life (36-item Short-Form Health Survey) were also assessed. Low frequency to high frequency power (LFHF) ratio was associated with physical fatigue (p = 0.019). Sample entropy was inversely associated with high-sensitivity C-reactive protein (p = 0.014) and myeloperoxidase (p = 0.007). There were no significant between-group differences in the changes in HRV derived parameters after the exercise intervention. High-sensitivity C-reactive protein and myeloperoxidase were negatively related to sample entropy and physical fatigue was positively related to LFHF ratio. However, an exercise intervention of 12 weeks of aerobic training did not produce any changes in HRV derived parameters in women with SLE in comparison to a control group.