Inflammatory suppression rapidly attenuates microvascular dysfunction in rheumatoid arthritis.

Rheumatoid arthritis (RA) is associated with greater risk of cardiovascular morbidity and mortality, the inflammatory component of RA being strongly linked to this excess risk. Endothelial dysfunction is linked to atherosclerosis and has been demonstrated in larger vessels in RA. In this pilot study, we determined for the first time whether skin microvascular function was impaired in patients with active RA and also determined its response to anti-inflammatory treatment. This was assessed non-invasively using laser Doppler imaging combined with iontophoresis of the vasodilators acetylcholine (ACh, endothelium dependent) and sodium nitroprusside (SNP, endothelium independent) to the forearm. Eight RA patients admitted for acute flare-ups were assessed before and following anti-inflammatory treatment. Standard laboratory indices were obtained along with pain perception (VAS). A control group of eight subjects was included for baseline comparison. Compared to this group, vascular function was substantially and significantly (P<0.00001) lower in RA patients. Following treatment, as CRP and VAS decreased, vascular function improved for both ACh (P<0.00001) and SNP (P=0.001), this improvement being significantly greater for ACh (P<0.001). Vascular dysfunction is evident in RA patients, even at the level of the cutaneous microcirculation, but improves as inflammation regresses. Assessment of cutaneous vascular function may be a useful, non-invasive surrogate indicator of vascular risk in RA, inclusive of myocardial microvascular abnormalities.

Microvascular function, metabolic syndrome, and novel risk factor status in women with cardiac syndrome X.

To characterize microvascular function, candidate risk pathways, and metabolic syndrome prevalence in women with cardiac syndrome X, 52 nondiabetic women with angiographically normal epicardial arteries but >1 mm of planar ST depression during exercise testing (patients) and 24 healthy controls of similar age were recruited. In addition to fasting blood samples and anthropometric measurements, forearm cutaneous microvascular function after iontophoresis of acetylcholine and sodium nitroprusside was assessed by laser Doppler imaging. Despite body mass index correction and a larger proportion on statin therapy, patients had high levels of insulin (p=0.016), triglycerides (p=0.018), intercellular adhesion molecule-1 (p=0.021), von Willebrand factor (p=0.005), and leptin (p=0.005) and lower levels of high-density lipoprotein cholesterol (p=0.042) compared with controls. Consistent with these data, 30% of patients but only 8% of controls fulfilled criteria for the metabolic syndrome as defined by the National Cholesterol Education Program (p=0.015). Endothelium-dependent and -independent microvascular functions were markedly impaired in patients (p<0.001), and the odds ratio for cardiac syndrome X was 7.38 (95% confidence interval 2.2 to 24.7) if the acetylcholine response was <8,710 flux units. In conclusion, women with cardiac syndrome X more commonly have metabolic syndrome and related adiposity, metabolic, and inflammatory derangements. They also have significantly impaired skin microvascular function as assessed by laser Doppler imaging, consistent with generalized vascular dysfunction, a finding with potential diagnostic implications.