Cardiovascular autonomic function in systemic lupus erythematosus

Cardiorespiratory Insufficiency and Performance Fatigability in Women with Systemic Lupus Erythematosus

Purpose

Patients with systemic lupus erythematosus (SLE) experience excessive, debilitating fatigue with previously reported evidence of etiologically mediated cardiorespiratory impairments. Performance fatigability provides a precise characterization of fatigue as it can be quantified objectively as a function of time, frequency, and/or duration. Nevertheless, little consideration has been given to understanding performance fatigability and its physiological determinants in those with SLE. The purpose of this study was to characterize performance fatigability in patients with SLE, utilizing measures surrounding the anaerobic threshold, with emphasis on cardiorespiratory impairment as a potential mediating factor.

Methods

This was a case-control study design. 44 physically inactive women, 26 with SLE and 18 controls, completed a treadmill cardiopulmonary exercise test to volitional exhaustion.

Results

There were no significant differences in age (SLE 34.8(9.0) vs Control 36.9(7.3) yrs; p=0.422) between groups. BMI (SLE 27.1(5.4) vs Control 23.8(5.2) kg/m2; p=0.045) was significantly higher in the SLE vs Control group. Resting heart rate (SLE 68(16) vs Control 78(15) bpm; p=0.040) was significantly lower in the SLE compared to the Control group. The VO2 corresponding to the anaerobic threshold (AT-VO2), used to identify the onset of exercise-induced fatigue, was significantly lower in women with SLE than in controls (SLE 12.4(3.1) vs Control 16.4(2.2) ml/kg/min; p<0.001), as was AT-stage (SLE 2.5(0.90) vs Control 3.4(0.78); p=0.002). Additionally, Fatigue Severity Score (FSS) was highly and inversely correlated with AT-VO2 (rho=-0.615; p<0.001) and FSS was highly correlated with Functional Aerobic Impairment Index (FAI; rho=0.663; p<0.001).

Conclusion

This study underscores severe performance fatigability in patients with SLE and its link to cardiorespiratory insufficiency. Physiological presentation of performance fatigability was observed during very low intensities of exercise, emphasizing the negative impact it may have on physical function in this population.

Intravenous cyclophosphamide treatment for systemic lupus erythematosus with severe autonomic disorders confirmed by head-up tilt table test: A case series

Autonomic disorders are common in patients with systemic lupus erythematosus (SLE), but the therapeutic strategy and methods for evaluating the effects of therapy have not been established. We describe the three cases of SLE patients who developed severe autonomic disorders as demonstrated by the head-up tilt table test (HUT). All three patients were treated by intensive immunosuppressive treatments including intravenous cyclophosphamide (IVCY); their HUT results all became negative. Our cases suggest that IVCY treatment can be a good therapeutic option for severe autonomic disorders in SLE patients. The HUT is a useful objective method for the diagnosis of and the evaluation of longitudinal therapeutic effects on autonomic disorders in SLE patients with orthostatic intolerance.

Cardiovascular reflex tests in patients with systemic lupus erythematosus: clinical performance and utility

Background

This review summarizes current knowledge about cardiovascular reflex tests (CVRTs) and other selected autonomic nervous system (ANS) assessment tests in systemic lupus erythematosus (SLE) patients and assesses their clinical utility in this group of patients.

Methods

The PubMed database was searched for terms associated with CVRTs and SLE. Only papers available in full text and published in English were considered. Ultimately, 13 were selected and analyzed.

Results

In most of the studies CVRTs results were reported more likely to be abnormal in patients with SLE when compared with controls. The reported prevalence of ANS dysfunction in SLE, diagnosed using CVRTs, ranged from 23.5% to 82.7% of patients, likely because of different definitions of ANS dysfunction, variability in methods of performing CVRTs, and potential confounding factors. In general CVRTs results did not correlate with SLE activity or disease duration, but some CVRTs results correlated with some peptides associated with ANS function, including neuropeptide Y and vasoactive intestinal peptide.

Conclusion

Patients with SLE generally have abnormal or borderline results of CVRTs, which indicate prevalent abnormalities of the ANS in SLE. Performance of CVRTs requires good standardization of test conditions and familiarity with the proper administration and interpretation of these tests.

The use of heart rate turbulence and heart rate variability in the assessment of autonomic regulation and circadian rhythm in patients with systemic lupus erythematosus without apparent heart disease

Background Systemic lupus erythematosus is a progressive autoimmune disease. There are reports suggesting that patients even without overt signs of cardiovascular complications have impaired autonomic function. The aim of this study was to assess autonomic function using heart rate turbulence and heart rate variability parameters indicated in 24-hour ECG Holter monitoring. Methods Twenty-six women with systemic lupus erythematosus and 30 healthy women were included. Twenty-four hour ambulatory ECG-Holter was performed in home conditions. The basic parameters of heart rate turbulence and heart rate variability were calculated. The analyses were performed for the entire day and separately for daytime activity and night time rest. Results There were no statistically significant differences in the basic anthropometric parameters. The mean duration of disease was 11.52 ± 7.42. There was a statistically significant higher turbulence onset (To) value in patients with systemic lupus erythematosus, median To = -0.17% (minimum -1.47, maximum 3.0) versus To = -1.36% (minimum -4.53, maximum -0.41), P < 0.001. There were no such differences for turbulence slope (Ts). In the 24-hour analysis almost all heart rate variability parameters were significantly lower in the systemic lupus erythematosus group than in the healthy controls, including SDANN and r-MSSD and p50NN. Concerning the morning activity and night resting periods, the results were similar as for the whole day. In the control group, higher values in morning activity were noted for parameters that characterise sympathetic activity, especially SDANN, and were significantly lower for parasympathetic parameters, including r-MSSD and p50NN, which prevailed at night. There were no statistically significant changes for systemic lupus erythematosus patients for p50NN and low and very low frequency. There was a positive correlation between disease duration and SDNN, R = 0.417; P < 0.05 and SDANN, R = 0.464; P < 0.05, a negative correlation between low/high frequency ratio and r-MSSD, R = -0.454; P < 0.05; p50NN, R = -0.435; P < 0.05 and high frequency, R = -0.478; P < 0.05. In contrast, there was no statistically significant correlation between heart rate turbulence and other variables evaluated, including disease duration and the type of autoantibodies.

CONCLUSION

Our study confirms the presence of autonomic disorders with respect to both heart rate variability and heart rate turbulence parameters and the presence of diurnal disturbances of sympathetic-parasympathetic balance. Further studies are required.

Systemic lupus erythematosus and exercise

Systemic lupus erythematosus (SLE) is a rheumatic disease characterized by a variety of symptoms, especially fatigue, pain and reduced quality of life. Physical exercise is a useful tool for improving cardiovascular fitness, reducing metabolic abnormalities and fatigue and improving quality of life. However, very few studies have focused on the relationship between SLE and physical exercise. This paper reviews the main SLE symptoms that can be alleviated by exercising, as well as the results of studies seeking to analyse the exercise capacity and physical training possibilities of SLE patients. Considerations for future research are also discussed.

The autonomic dysfunction in patients with lupus disease: An electrophysiological study

Background:

The aim of this study was to investigate autonomic nervous system (ANS) function by using electrophysiological tests in patients with systemic lupus erythematosus (SLE).

Materials and Methods:

This descriptive analytical study was done on 28 individuals with a history of lupus and ten age- and sex-matched healthy objects were being selected randomly. The autonomy questionnaire has been used to determine clinical symptom of ANS involvement. The electrophysiological assessments of ANS function were performed by sympathetic skin response (SSR). The mean values of sympathetic (SSR latency and amplitude) parameters were compared to determine any correlations between SSR parameters and clinical characteristics of ANS.

Results:

28 SLE patients (3 males, 25 females) with a mean age of 34.6 ± 9.74 years and 10 control subjects (4 males, 6 females) with a mean age of 36.8 ± 6.43 years were included in the study. Among patients 17 (60.7%) exhibited autonomic symptoms. Headache was the most common issue with the highest percentage rate (41.17%). The mean latency and amplitude of SSR were increased (1.52 ± 0.16 vs. 1.39 ± 0.16 and 107 ± 15.6 vs. 110 ± 15.6, respectively), compared to control. A significant difference was observed between the SSR test results of patients with lupus compared to normal healthy objects (P < 0.05). R = 0.43 correlation was found between autonomy questionnaire scores and SSR (P < 0.05).

Conclusion:

It could be concluded that latency measures in SSR test can be used as a valuable and accurate evaluation guideline for autonomic system assessment.

Middle cerebral artery resistivity and pulsatility indices in systemic lupus erythematosus: evidence for hyperperfusion

BACKGROUND AND PURPOSE

Systemic lupus erythematosus (SLE) is associated with significant cerebrovascular and neuropsychiatric disease for which multiple pathogeneses have been proposed. Although global cerebral hypoperfusion has been proposed, there are limited data about intracerebral arterial hemodynamics. Transcranial Doppler (TCD) allows portable, high temporal and spatial resolution, noninvasive blood velocity measurements in the middle cerebral arteries, and calculations of standard resistivity (RI) and pulsatility (PI) indices. RI and PI correlate with cerebral hemispheric arteriolar tone, blood flow resistances, and impedances. Accordingly, we hypothesized that there would be significant differences (p < 0.05) in RI and PI between SLE patients and healthy, age and gender matched controls.

METHODS

TCD was used to measure RI and PI bilaterally on 34 stable SLE patients (35 ± 11 years) and 15 control subjects (34 ± 10 years). Patients and controls had similar, normal blood pressures and were examined in the supine position during normal, resting respiration. RI and PI were determined by a blinded, experienced observer.

RESULTS

There were no significant differences in RI and PI bilaterally within each cohort. However, SLE patients had significantly lower average RI and PI values compared with controls: 0.45 ± 0.10 versus 0.52 ± 0.05 (p < 0.05); and 0.65 ± 0.19 versus 0.77 ± 0.12, (p < 0.05); respectively.

CONCLUSIONS

These preliminary data suggest that RI and PI values in the human middle cerebral artery are significantly lower in SLE compared with controls. These indices indicate that middle cerebral arterial resistances and impedances are decreased in SLE. Under normotensive conditions, the results are consistent with hyperperfusion in SLE with increased arteriolar dilation and increased cerebral blood flow.

Brain hypoperfusion in a girl with systemic lupus erythematosus

We describe an adolescent girl with systemic lupus erythematosus, presenting with severe cardiovascular autonomic dysfunction and incapacitating orthostatic hypotension to a degree not previously reported. Further evaluation of cerebral blood flow velocity, using transcranial Doppler testing, demonstrated an abnormal hypercapnic cerebrovascular response. Both the orthostatic hypotension and the abnormal cerebrovascular hypercapnic response improved with intensive medical treatment of her systemic lupus erythematosus. Additional studies are necessary to elucidate the pathogenesis of these cerebrovascular and autonomic abnormalities, especially considering the potential consequences they may exert on cerebral perfusion, which may be subtle, underrecognized, and capable of affecting cognition.

Experimental stress in inflammatory rheumatic diseases: a review of psychophysiological stress responses

Introduction

Stressful events are thought to contribute to the aetiology, maintenance and exacerbation of rheumatic diseases. Given the growing interest in acute stress responses and disease, this review investigates the impact of real-life experimental psychosocial, cognitive, exercise and sensory stressors on autonomic, neuroendocrine and immune function in patients with inflammatory rheumatic diseases.

Methods

Databases Medline, PsychINFO, Embase, Cinahl and Pubmed were screened for studies (1985 to 2009) investigating physiological stress responses in inflammatory rheumatic diseases. Eighteen articles met the inclusion criteria.

Results

Results suggest that immune function may be altered in response to a stressor; such alterations could contribute to the maintenance or exacerbation of inflammatory rheumatic diseases during stressful events in daily life.

Conclusions

This review emphasizes the need for more experimental research in rheumatic populations with controlled stress paradigms that include a follow-up with multiple evaluation points, simultaneous assessment of different physiological stress systems, and studying factors contributing to specific physiological responses, such as stress appraisal.

Autonomic dysfunction in autoimmune rheumatic disease

Cardiovascular and neurological manifestations are known to occur in patients with autoimmune rheumatic disease (ARD), often in subclinical form. The term autonomic nervous system (ANS) describes nerves that are concerned predominantly with the regulation of bodily functions. It is comprised of sympathetic and parasympathetic nerves, and their function is complementary. ANS involvement has rarely been studied in patients with ARD, and studies have shown conflicting results. This may be because symptoms of autonomic dysfunction are nonspecific and extremely varied, and may pertain to several systems like the gastrointestinal, cardiovascular, and nervous. Moreover, tests to detect autonomic dysfunction are not routinely employed in clinical rheumatological practice. Another difficulty is to differentiate cardiovascular effects of drugs from ARD involvement. Previous studies on this topic found signs of parasympathetic and sympathetic dysfunction in variable proportions in patients with autoimmune diseases, between 24% and 100% in various tests depending on the methods used. Cardiovascular autonomic dysfunction is the most common type of ANS dysfunction, and was revealed in the majority of ARD patients.

Cardiovascular autonomic dysfunction in systemic lupus, rheumatoid arthritis, primary Sjögren syndrome and other autoimmune diseases

Neurological manifestations are known to occur in patients with autoimmune diseases, often subclinically, but autonomic nervous system (ANS) involvement has rarely been studied, and studies have shown conflicting results. We performed cardiovascular ANS assessment in 125 patients with autoimmune diseases in this case-control study, including 54 patients with systemic lupus erythematosus (SLE), 39 with rheumatoid arthritis (RA), 20 with primary Sjbgren syndrome (pSS), eight patients with polymyalgia rheumatica (PR), four patients with scleroderma (Ssc) and 35 healthy control subjects. The control group was formed to approximately match the mean age of SLE, RA and pSS patients; controls did not differ significantly by gender from the autoimmune pations. All patients with were in stable condition. Autonomic nervous system dysfunction was diagnosed by applying cardiovascular reflex tests according to Ewing, and was considered to exist if at least two tests were positive. Vagal dysfunction was established by applying three tests: Valsalva manoeuvre, deep breathing test, and heart rate response to standing. Sympathetic dysfunction was examined by applying two tests: blood pressure response to standing and handgrip test. In all cardiovascular reflex tests, frequencies of abnormal results were significantly higher among the patients than among the controls (P < 0.05). The difference between the autoimmune patients and the controls was particularly significant in sympathetic and parasympathetic tests, with P < 0.0001. No correlation was found between disease duration, clinical manifestations, cardiovascular risk factors and diseases activity on the one hand, and ANS dysfunction on the other hand. Cardiovascular autonomic dysfunction was revealed in the majority of autoimmune patients.

Autonomic dysfunction in systemic lupus erythematosus

The objectives were to study the frequency and pattern of autonomic dysfunction in systemic lupus erythematosus (SLE). Fifty-one patients of SLE and 30 age- and sex-matched healthy controls were studied prospectively using a standard battery of noninvasive tests. Autonomic symptoms were seen in 37% patients. On laboratory testing incipient dysfunction was seen in 9 (18%) cases and 1 (3%) control, while atypical involvement was seen in 11 (21%) cases and 6 (20%) controls. Autonomic dysfunction did not correlate with disease duration, lupus activity, disease damage, any particular organ involvement or the presence/absence of peripheral neuropathy. Autonomic neuropathy is not uncommon in lupus and may exist independent of peripheral neuropathy. There are no specific clinical predictors. The clinical significance of autonomic dysfunction detected by laboratory testing warrants longitudinal studies.