Subclinical impairment of arterial mechanics in systemic lupus erythematosus identified by arterial waveform analysis

Suppression of inflammation reduces endothelial microparticles in active systemic lupus erythematosus

Background

In a prospective observational study, we investigated whether patients with active systemic lupus erythematosus (SLE) had higher indices of endothelial damage and dysfunction than healthy controls and whether improved disease control was associated with improvement in these indices.

Methods

Twenty-seven patients with active SLE (four or more American College of Rheumatology (ACR) criteria) and 22 age-matched controls were assessed. Endothelial microparticles (EMPs; CD31+/annexin V+/CD42b−) were quantified using flow cytometry. Brachial artery flow-mediated dilatation (FMD) was measured using automated edge-tracking software. Twenty-two patients had a second assessment at a median (IQR) of 20 (16, 22) weeks after initiating new immunosuppressive therapy.

Results

SLE patients had a median (IQR) baseline global British Isles Lupus Assessment Group Disease Activity Index (BILAG-2004) score of 14 (12, 22). CD31+/annexin V+/CD42b− EMPs were higher (157 548/ml (59 906, 272 643) vs 41 025(30 179, 98 082); p=0.003) and endothelial-dependent FMD was lower (1.63% (−1.22, 5.32) vs 5.40% (3.02, 8.57); p=0.05) in SLE patients than controls. CD31+/annexin V+/CD42b− EMPs correlated inversely with FMD (%) (r² −0.40; p=0.006). At follow-up, the median (IQR) change in global BILAG-2004 score was −11 (−18, −3). CD31+/annexin V+/CD42b− EMP levels were reduced (166 982/ml (59 906, 278 775 vs 55 655(29 475, 188 659; p=0.02) and FMD had improved (0.33% (−2.31, 4.1) vs 3.19% (0.98, 5.09); p=0.1) at the second visit.

Conclusions

Active SLE is associated with evidence of increased endothelial damage and endothelial dysfunction, which improved with suppression of inflammation. Better control of active inflammatory disease may contribute to improved cardiovascular risk in patients with SLE.

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).

Colour Doppler ultrasound of the ocular circulation in patients with systemic lupus erythematosus identifies altered microcirculatory haemodynamics

We assessed whether quantitative analysis of Doppler flow velocity waveforms is able to identify subclinical microvascular abnormalities in SLE and whether eigenvector analysis can detect changes not detectable using the resistive index (RI). Fifty-four SLE patients with no conventional cardiovascular risk factors, major organ involvement or retinopathy were compared to 32 controls. Flow velocity waveforms were obtained from the ophthalmic artery (OA), central retinal artery (CRA) and common carotid artery (CA). The waveforms were analysed using eigenvector decomposition and compared between groups at each arterial site. The RI was also determined. The RI was comparable between groups. In the OA and CRA, there were significant differences in the lower frequency sinusoidal components ( P < 0.05 for each component). No differences were apparent in the CA between groups. Eigenvector analysis of Doppler flow waveforms, recorded in proximity of the terminal vascular bed, identified altered ocular microvascular haemodynamics in SLE. Altered waveform structure could not be identified by changes in RI, the traditional measure of downstream vascular resistance. This analytical approach to waveform analysis is more sensitive in detecting preclinical microvascular abnormalities in SLE. It may hold potential as a useful tool for assessing disease activity, response to treatment, and predicting future vascular complications.