A comparative study of arterial stiffness, flow-mediated vasodilation of the brachial artery, and the thickness of the carotid artery intima–media in patients with systemic autoimmune diseases

The prevalence of abnormal pulse wave velocity, pulse contour analysis and ankle-brachial index in patients with livedo reticularis: a controlled study

OBJECTIVE

To evaluate the prevalence of abnormal pulse wave velocity (PWV), pulse contour analysis (PCA) and abnormal ankle-brachial pressure index (ABPI) in patients with livedo reticularis (livedo) and without livedo.

METHODS

We recruited 74 patients, of whom 41 had livedo: 16 APS, 9 APS with SLE and 16 with livedo (negative for aPL or lupus). The other group of 33 patients without livedo consisted of 10 APS, 8 APS with SLE and 15 with SLE only. Livedo was diagnosed and confirmed by a dermatologist. PWV was assessed in fasting patients by the Micro Medical PulseTrace analyser using a 4 MHz continuous-wave directional Doppler probe and digital PCA was analysed by Micro Medical PulseTrace by the same operator. Chi-square with Yates's correction was used for comparing results.

RESULTS

The median age of the livedo patients was 46 (29-71) years and of the non-livedo patients was 45 (25-68) years. Abnormal values of PWV in 10/41 (24.40%), ABPI in 4/41 (9.8%) and PCA in 10/41 (24.40%) patients were observed in the livedo group and in the non-livedo group abnormal values of PWV in 1/33 (P ≤ 0.025), ABPI in 0/33 (P = NS) and PCA in 5/33 (P = NS) were observed.

CONCLUSION

Patients with livedo reticularis are more likely to have abnormal PWV, indicating arterial stiffness.

Endothelial dysfunction in rheumatic autoimmune diseases

Rheumatic autoimmune diseases have been associated with accelerated atherosclerosis and various types of vasculopathies. Atherosclerosis is an inflammatory condition which starts as a "response to injury" favoring endothelial dysfunction which is associated with increased expression of adhesion molecules, pro-inflammatory cytokines, pro-thrombotic factors, oxidative stress upregulation and abnormal vascular tone modulation. Endothelial dysfunction in rheumatic autoimmune diseases involves innate immune responses, including macrophages and dendritic cells expression of scavenger and toll-like receptors for modified or native LDL as well as neutrophil and complement activation, and dysregulation of adaptive immune responses, including proliferation of autoreactive T-helper-1 lymphocytes and defective function of dendritic and regulatory T cells. Specific differences for endothelial function among different disorders include: a) increased amounts of pro-atherogenic hormones, decreased amounts of anti-atherogenic hormones and increased insulin resistance in rheumatoid arthritis; b) autoantibodies production in systemic lupus erythematosus and antiphospholipid syndrome; c) smooth muscle cells proliferation, destruction of internal elastic lamina, fibrosis and coagulation and fibrinolytic system dysfunction in systemic sclerosis. Several self-antigens (i.e. high density lipoproteins, heat shock proteins, β2-glycoprotein1) and self-molecules modified by oxidative events (i.e. low density lipoproteins and oxidized hemoglobin) have been identified as targets of autoimmune responses. Endothelial dysfunction leads to accelerated atherosclerosis in rheumatoid arthritis, systemic lupus erythematosus and spondyloarthropaties whereas obliterative vasculopathy is associated with systemic sclerosis. In this paper, we will briefly review the most relevant information upon endothelial dysfunction and inflammatory mechanisms in atherosclerosis and we will summarize the similarities and differences in vascular disease patterns underlying different rheumatic autoimmune diseases.

Cyclooxygenase inhibition augments central blood pressure and aortic wave reflection in aging humans

The augmentation index and central blood pressure increase with normal aging. Recently, cyclooxygenase (COX) inhibitors, commonly used for the treatment of pain, have been associated with transient increases in the risk of cardiovascular events. We examined the effects of the COX inhibitor indomethacin (Indo) on central arterial hemodynamics and wave reflection characteristics in young and old healthy adults. High-fidelity radial arterial pressure waveforms were measured noninvasively by applanation tonometry before (control) and after Indo treatment in young (25 ± 5 yr, 7 men and 6 women) and old (64 ± 6 yr, 5 men and 6 women) subjects. Aortic systolic (control: 115 ± 3 mmHg vs. Indo: 125 ± 5 mmHg, P < 0.05) and diastolic (control: 74 ± 2 mmHg vs. Indo: 79 ± 3 mmHg, P < 0.05) pressures were elevated after Indo treatment in older subjects, whereas only diastolic pressure was elevated in young subjects (control: 71 ± 2 mmHg vs. Indo: 76 ± 1 mmHg, P < 0.05). Mean arterial pressure increased in both young and old adults after Indo treatment (P < 0.05). The aortic augmentation index and augmented pressure were elevated after Indo treatment in older subjects (control: 30 ± 5% vs. Indo 36 ± 6% and control 12 ± 1 mmHg vs. Indo: 18 ± 2 mmHg, respectively, P < 0.05), whereas pulse pressure amplification decreased (change: 8 ± 3%, P < 0.05). In addition, older subjects had a 61 ± 11% increase in wasted left ventricular energy after Indo treatment (P < 0.05). In contrast, young subjects showed no significant changes in any of the variables of interest. Taken together, these results demonstrate that COX inhibition with Indo unfavorably increases central wave reflection and augments aortic pressure in old but not young subjects. Our results suggest that aging individuals have a limited ability to compensate for the acute hemodynamic changes caused by systemic COX inhibition.

Validated methods for assessment of subclinical atherosclerosis in rheumatology

Rheumatoid arthritis, as well as other types of arthritides and connective tissue diseases, is associated with accelerated atherosclerosis, and increased cardiovascular morbidity and mortality. The early signs of cardiovascular disease therefore need to be recognized in patients with these conditions so that effective cardiovascular protection can be introduced. This Review provides an overview of validated techniques that are currently available to determine subclinical atherosclerosis in patients with rheumatic conditions. Techniques for early assessment of endothelial dysfunction include brachial artery flow-mediated vasodilation and laser Doppler flowmetry. Coronary circulation can be assessed by measuring coronary flow reserve using CT, MRI or PET based techniques. The standard indicators of arterial stiffness are pulse-wave velocity and the augmentation index. Carotid atherosclerosis is determined by the common carotid intima-media thickness (ccIMT) measurement or by the assessment of plaques and plaque areas. The combination of ccIMT with plaque assessment is likely to increase the predictive value of this approach. The potential use of a multimarker approach to increase the diagnostic and prognostic value of these clinical assessments is also discussed.

Changes in vascular function and structure in juvenile idiopathic arthritis

OBJECTIVE

Chronic inflammatory diseases in adults have been associated with increased cardiovascular risk and impaired vascular function. We aimed to assess the presence of early vascular dysfunction in patients with juvenile idiopathic arthritis (JIA) and investigate the role of inherent inflammatory process of JIA in vascular health.

METHODS

Thirty patients with JIA (age range 7-18 years) were compared to 33 age- and sex-matched controls. Endothelial function (brachial artery flow-mediated dilation [FMD]), carotid intima-media thickness (IMT), and arterial stiffness were examined. Endothelial inflammation was assessed by intercellular adhesion molecule 1 (ICAM-1) and P-selectin measurements.

RESULTS

Patients with JIA showed decreased FMD compared to controls (P = 0.001), independent of age (P = 0.9 among age subgroups). Baseline differences in erythrocyte sedimentation rate, ICAM-1, and glucose between the 2 groups accounted for the difference in FMD. The presence of systemic JIA was associated with greater IMT compared to patients with oligoarticular disease, polyarticular disease, or controls (P = 0.014, P = 0.069, and P = 0.046, respectively). The difference in IMT between systemic versus oligoarticular/polyarticular JIA was attributed to the following risk factors: age, body mass index, blood pressure, disease activity, and corticosteroids use. There were no differences in arterial stiffness indices between JIA patients and controls or between patients with systemic versus nonsystemic disease.

CONCLUSION

Endothelial function is impaired in patients with JIA at a very young age, while IMT is increased only in the presence of systemic JIA. Vascular dysfunction may be partly attributed to the effects of disease-related characteristics (inflammation, disease activity, and medications).

Vascular function and morphology in rheumatoid arthritis: a systematic review

OBJECTIVES

RA associates with significantly increased morbidity and mortality from cardiovascular disease (CVD). This may be due to complex interactions between traditional CVD risk factors, systemic rheumatoid inflammation and the vasculature. We reviewed the current literature to answer: (i) whether there is sufficient evidence that patients with RA have altered vascular function and morphology compared with normal controls; (ii) whether there is sufficient evidence to determine if such changes relate predominantly to systemic inflammation; and (iii) whether any changes of vascular function and morphology in RA can be modified with therapy.

METHODS

The MEDLINE database was searched to identify publications from 1974 to 1 November 2010 pertaining to vascular function and morphology in RA. The total number of articles included in the present review was 93. This included 57 cross-sectional studies, 27 longitudinal studies without randomization and 9 longitudinal studies with randomization.

RESULTS

Vascular function and morphology was impaired in RA relative to healthy controls. The majority of studies reported no associations between systemic inflammation and vascular function. Treatment with anti-inflammatory medication resulted in both transient and long-term improvements in the vasculature, but only a few studies reported associations between change in inflammation and change in vascular function and morphology.

CONCLUSION

The link between systemic inflammation and vascular function and morphology is not wholly supported by the available literature. Long-term studies examining specific predictors (including CVD risk factors) on the vasculature in RA are needed.

Endothelial function and oxidative stress in chronic kidney disease of varying severity and the effect of acute hemodialysis

AIM

Oxidative stress (OS) and endothelial dysfunction are implicated in accelerated atherosclerosis in chronic kidney disease (CKD). We assessed endothelial function, OS, and carotid intimal medial thickness (CIMT) and their correlates in 44 CKD stage 5 patients (group III) before and after hemodialysis (HD), 40 patients of CKD stages 3 and 4 (group II), and 25 matched controls (group I).

METHODS

OS was measured by serum concentration of antioxidants; vitamin C and fractional reducing ability of plasma (FRAP) and pro-oxidant; thiobarbituric acid reactive substances (TBARS). Ultrasonography of carotid artery for CIMT and of brachial artery for flow-mediated dilatation (endothelium-dependent dilatation, EDD) was done.

RESULTS

TBARS increased significantly with severity of CKD. Antioxidants FRAP and vitamin C were significantly lower in CKD patients as compared with controls, but there was no significant difference between groups II and III. EDD decreased significantly with severity of CKD, whereas CIMT though higher in CKD patients as compared with controls was not significantly different between groups II and III. After a session of HD as compared with predialysis, levels of TBARS decreased, whereas those of FRAP, vitamin C, and EDD increased. On multivariate analysis, there was negative correlation of TBARS with glomerular filtration rate (GFR), serum albumin, hemoglobin, and EDD. Vitamin C had positive correlations with GFR, serum albumin, hemoglobin, and EDD. EDD had direct correlation with GFR, whereas CIMT correlated negatively with EDD.

CONCLUSIONS

Endothelial dysfunction and OS occur early in CKD, are closely related to each other and structural atherosclerosis, and are proportional to decline in GFR.

Arterial pulse wave velocity in relation to carotid intima-media thickness, brachial flow-mediated dilation and carotid artery distensibility: the Cardiovascular Risk in Young Finns Study and the Health 2000 Survey

OBJECTIVE

Increased arterial pulse wave velocity (PWV) is a strong predictor of cardiovascular events and mortality. The data regarding the relationships between PWV and other indices of vascular damage is limited and partly controversial. We conducted the present study to examine PWV in relation to non-invasive measures of early atherosclerosis (brachial flow-mediated dilation [FMD], carotid intima-media thickness [IMT]) and local arterial stiffness (carotid artery distensibility [Cdist]).

METHODS

The study population consisted of 1754 young adults (aged 30-45 years, 45.5% males) participating in the Cardiovascular Risk in Young Finns Study (YFS), and of 336 older adults (aged 46-76 years, 43.2% males) participating in the Health 2000 Survey. FMD was measured only in the YFS cohort. FMD, IMT and Cdist were assessed by ultrasound, and PWV was measured using the whole-body impedance cardiography device.

RESULTS

In young adults, FMD and IMT were not associated with PWV independently of cardiovascular risk factors. Moreover, FMD status was not found to modulate the association between cardiovascular risk factors and PWV. In older adults, PWV and IMT were directly and independently associated (β=1.233, p=0.019). In both cohorts, PWV was inversely related with Cdist, and this relation remained significant (p<0.04) in models adjusted for cardiovascular risk factors.

CONCLUSIONS

The current findings suggest that PWV reflects a different aspect of vascular damage than FMD or IMT in young adults, whereas in older adults the information provided by PWV and IMT may be, to some extent, similar as regards subclinical vascular damage. The present observations also suggest that PWV and Cdist represent, at least in part, a similar adverse vascular wall process.

Early Identification of Vascular Damage in Patients With Systemic Sclerosis

Vascular involvement in systemic sclerosis (SSc) plays a key role in the pathogenesis of fibrosis. We assessed arterial stiffness using a new echo-tracking technique in patients with SSc asymptomatic for cardiovascular diseases. We enrolled 22 patients (21 female, 63 ± 14 years) and 20 controls (12 female, 62 ± 3 years). Carotid intima-media thickness (IMT) was comparable between the 2 groups (1.1 ± 0.3 vs 1.0 ± 0.4 mm, P = ns), whereas the stiffness parameters were significantly increased in patients (β: 9.5 ± 4.2 vs 5.8 ± 1.1, P = .001; pulse wave velocity [PWV]: 6.5 ± 1.5 vs 5.2 ± 0.6 m/sec, P = .003). A correlation between stiffness parameters, anti-Scl-70 antibodies (β: r = .46, P = .03; PWV: r = .50, P = .02), and anticentromere antibodies (β: r = -.54, P = .020; PWV: r = -.53, P = .023) was found. Echo-tracking technique may be valuable in early identification of vascular involvement in patients with SSc.

Comparative assessment of vascular function in autoimmune rheumatic diseases: considerations of prevention and treatment

Numerous autoimmune-inflammatory rheumatic diseases have been associated with accelerated atherosclerosis or other types of vasculopathy leading to increased cardio- and cerebrovascular disease risk. Traditional risk factors, as well as the role of systemic inflammation including cytokines, chemokines, proteases, autoantibodies, adhesion receptors and others have been implicated in the development of these vascular pathologies. The characteristics of vasculopathies may significantly differ depending on the underlying disease. While classical accelerated atherosclerosis has been associated with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) or spondyloarthropathies (SpA), obliterative vasculopathy may rather be characteristic for systemic sclerosis (SSc) or mixed connective tissue disease (MCTD). Antiphospholipid antibodies have been implicated in vasculopathies underlying SLE, antiphospholipid syndrome (APS), RA and MCTD. There is also heterogeneity with respect to inflammatory risk factors. Cytokines, such as tumor necrosis factor-α (TNF-α) or interleukin 6 (IL-6) and immune complexes are primarily involved in arthritides, such as RA, SpA, as well as in SLE. On the other hand, autoantibodies including anti-oxLDL anti-cardiolipin and anti-β2GPI are rather involved in SLE- and APS-associated vasculopathies. Regarding the non-invasive assessment of vascular function, endothelial dysfunction, overt atherosclerosis and vascular stiffness may be indicated by brachial artery flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT) and aortic pulse-wave velocity (PWV), respectively. These abnormalities have been described in most inflammatory rheumatic diseases. While ccIMT and stiffness are relatively stable, FMD may be influenced by many confounding factors. In addition to traditional vasculoprotection, immunosuppressive agents including corticosteroids, traditional and biologic DMARDs may have significant vascular and metabolic effects. The official EULAR recommendations on the assessment and management of cardiovascular disease in arthritides have just been published, and similar recommendations in connective tissue diseases are to be developed soon.

Assessment of subclinical vascular disease associated with ankylosing spondylitis

OBJECTIVE

Studies indicate that ankylosing spondylitis (AS), as well as rheumatoid arthritis, may be associated with accelerated atherosclerosis and vascular disease. We assessed endothelial dysfunction, carotid atherosclerosis, and aortic stiffness in AS in context with clinical and laboratory measurements.

METHODS

Forty-three patients with AS and 40 matched healthy controls were studied. We assessed common carotid intima-media thickness (ccIMT), flow-mediated vasodilation (FMD), and pulse-wave velocity (PWV) in association with age, disease duration, smoking habits, body mass index, patient's assessment of pain and disease activity, Bath AS Disease Activity Index, Bath AS Functional Index (BASFI), metric measurements, erythrocyte sedimentation rate, C-reactive protein, and HLA-B27 status.

RESULTS

We found impaired FMD (6.85 ± 2.98% vs 8.30 ± 3.96%; p = 0.005), increased ccIMT (0.65 ± 0.15 vs 0.54 ± 0.15 mm; p = 0.01), and higher PWV (8.64 ± 2.44 vs 8.00 ± 1.46 m/s; p = 0.03) in patients with AS compared to controls, respectively. We also found that ccIMT negatively correlated with FMD (r = -0.563; p = 0.0001) and positively correlated with PWV (r = 0.374; p = 0.018). Both ccIMT and PWV correlated with disease duration (r = 0.559; p = 0.013 and r = 0.520; p = 0.022, respectively), BASFI (r = 0.691; p = 0.003 and r = 0.654; p = 0.006), decreased lumbar spine mobility (r = -0.656; p = 0.006 and r = -0.604; p = 0.013), chest expansion (r = -0.502; p = 0.047 and r = -0.613; p = 0.012), and increased wall-occiput distance (r = 0.509; p = 0.044 and r = 0.614; p = 0.011).

CONCLUSION

In this well characterized AS population, impaired FMD and increased ccIMT and PWV indicate abnormal endothelial function and increased atherosclerosis and aortic stiffness, respectively. The value of noninvasive diagnostic tools needs to be further characterized.

Biologics - beyond the joints

Biologics including tumor necrosis factor α (TNF-α), interleukin-6 receptor (IL-6R), T and B cell inhibitors are very effective therapeutic agents for the treatment of arthritides. These compounds effectively improve articular symptoms and inhibit joint damage. In this respect, there are no major differences in the efficacy of the available biologics. However, many arthritis patients also exert extra-articular features, systemic manifestations of the disease. These associated conditions include uveitis, inflammatory bowel disease, psoriasis, secondary bone loss and cardiovascular disease. There have been data suggesting that there may be differences in the effects of various TNF inhibitors, rituximab and tocilizumab on the systemic manifestations described above. At present, we do not always have sufficient evidence to confirm these differences, therefore, more information should be obtained from large trials and long-term observational studies.

Effects of prasterone (dehydroepiandrosterone) on markers of cardiovascular risk and bone turnover in premenopausal women with systemic lupus erythematosus: a pilot study

DHEA (dehydroepiandrosterone) is a weak androgen with proposed efficacy in the treatment of mild to moderate lupus, and possible beneficial effects on cardiovascular risk and bone mineral density. We hypothesized that treatment with 200 mg a day of Prasterone (DHEA) would improve pre-clinical measures of atherosclerosis: flow-mediated dilatation (FMD), nitroglycerin-mediated dilatation (NMD), and circulating apoptotic endothelial cells (CD 146(AnnV +)), as well markers of bone metabolism. Thirteen premenopausal female patients with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) <or=8 were enrolled in a double-blind placebo-controlled crossover trial for 22 weeks with a 6-week washout between treatment periods. Results reveal high-density lipoprotein (HDL) levels significantly decreased with Prasterone (48.5 versus 56.3 with placebo, p <or= 0.001), and there was a trend towards impairment of endothelial function with Prasterone (brachial artery FMD 3.4% versus 4.4% with placebo, mean difference -1.07, NMD 19.5% versus 24.4% with placebo, mean difference -4.9, p = NS). There were no differences between groups in SLEDAI, CD146( AnnV+) cells, or receptor activator for nuclear factor kB ligand (RANKL)/osteoprotegerin, although RANKL was higher after treatment with Prasterone (mean difference -29.5 units; p = 0.097). This pilot study does not support the use of Prasterone in mild lupus for prevention of atherosclerosis or osteoporosis, and confirms other findings of potentially harmful effects on lipids.

The effect of smoking on arterial stiffness

A systematic literature review was conducted using PubMed, Embase and the Cochrane Library to determine the effect of acute, chronic and passive smoking on arterial stiffness and to determine whether these effects are reversible after smoking cessation. A total of 39 relevant studies were identified and included. Acute smoking was found to cause an acute increase in arterial stiffness. Similarly, passive smoking increased arterial stiffness acutely and chronically. The majority of studies identified chronic smoking as a risk factor for increasing arterial stiffness. However, some studies found no statistical difference in arterial stiffness between nonsmokers and long-term smokers, although chronic smoking seems to sensitize the arterial response to acute smoking. In addition, whether arterial stiffness is reversed after smoking cessation and the timeline in which this may occur could not be determined from the identified literature. The effect of smoking discontinuation on arterial stiffness remains to be established by prospective smoking cessation trials.

A distinct subset of proinflammatory neutrophils isolated from patients with systemic lupus erythematosus induces vascular damage and synthesizes type I IFNs

Neutrophil-specific genes are abundant in PBMC microarrays from lupus patients because of the presence of low-density granulocytes (LDGs) in mononuclear cell fractions. The functionality and pathogenicity of these LDGs have not been characterized. We developed a technique to purify LDGs from lupus PBMCs and assessed their phenotype, function, and potential role in disease pathogenesis. LDGs, their autologous lupus neutrophils, and healthy control neutrophils were compared with regard to their microbicidal and phagocytic capacities, generation of reactive oxygen species, activation status, inflammatory cytokine profile, and type I IFN expression and signatures. The capacity of LDGs to kill endothelial cells and their antiangiogenic potential were also assessed. LDGs display an activated phenotype, secrete increased levels of type I IFNs, TNF-alpha, and IFN-gamma, but show impaired phagocytic potential. LDGs induce significant endothelial cell cytotoxicity and synthesize sufficient levels of type I IFNs to disrupt the capacity of endothelial progenitor cells to differentiate into mature endothelial cells. LDG depletion restores the functional capacity of endothelial progenitor cells. We conclude that lupus LDGs are proinflammatory and display pathogenic features, including the capacity to synthesize type I IFNs. They may play an important dual role in premature cardiovascular disease development in systemic lupus erythematosus by simultaneously mediating enhanced vascular damage and inhibiting vascular repair.