Background Endothelial dysfunction is considered as a link between chronic, systemic inflammatory process in rheumatoid arthritis (RA) and initiation of atherosclerosis process. Microvascular dysfunction may precede the beginning of atherosclerosis and predispose RA patients to development of cardiovascular disease (CVD) (1). In patients with longstanding RA, microvascular function is impaired and associated with activity of disease (DAS28).
Recently, it has been demonstrated that microvascular endothelium-dependent vasodilatation and capillary recruitment is preserved in early disease-modifying antirheumatic drugs (DMARD)-naive patients (2). However, there is no information about skin hyperaemic heat response which is an integrated index of neurovascular and nitric oxide-dependent cutaneous blood flow regulation (3).
Objectives Present study was performed to investigate disorders in macro- and microcirculation in newly diagnosed, (DMARD)-naive patients with RA and healthy controls.
Methods Twenty nine patients (22 women, 7 men) at the age of 40,96±9,45 years, with active early RA (DAS28: 4,41±1,79, with history of symptoms - mean 16,3 months) and twenty nine healthy controls (13 women, 16 men) at the age of 31,65±7,64 years were recruited. Blood pressure (BP), body mass index (BMI) and waist to hip ratio (WHR) were measured and blood samples were collected to estimate inflammation (ESR, CRP, hsTNFalfa and hsIL6), CV risk factors (lipids, glucose), biochemical marker of endothelial dysfunction (von Willenbrand factor - vWF) and RF, aCCP in RA group. Presence of atherosclerosis in macrovascular bed was assessed by measurements of intima-media thickness (IMT) using B-mode ultrasonography. Skin microcirculation reaction during local heat stress was assessed noninvasively using laser Doppler flowmetry (LDF, Periflux 5000).
Results There were no significant differences between groups in values of BP, BMI, WHR and levels of lipids and glucose. As expected patients with RA had significantly higher CRP, ESR, hsTNFalfa and hsIL6 levels. VWF (%) was also higher in RA patients (109,75±48,6 vs 73,7±22,39, p=0,005). The study groups were similar in IMT, however differed in LDF parameters of flow during local heat stress. Time to maximal heat flow (sec) was increased [17,01±4,35 vs 11,14±5,36 (p=0,04)] and maximal heat flow velocity (U/min) was lower [10,43±5,49 vs 24,67±24,1 (p=0,03)] in patients with RA. All results were age and sex standardized.
Conclusions Microvascular dysfunction preceding the onset of atherosclerosis in early active rheumatoid arthritis is represented by alteration in microcirculation response to thermal stress.
A. Sandoo, C. Douglas, GS. Metsios et al. The association between microvascular and macrovascular endothelial function in patients with rheumatoid arthritis: a cross–sectional study. Arthritis Res Ther 2011; 13:R99.
van Eijk IC, Serné EH, Dijkmans BA, Smulders Y, Nurmohamed M. Microvascular function is preserved in newly diagnosed rheumatoid arthritis and low systemic inflammatory activity. Clin Rheumatol 2011;30(8):1113-8.
Charkoudian N. Skin blood flow in adult human thermoregulation: How it works, when it does not, and why. Mayo Clin Proc 2003;78:603-612.
Disclosure of Interest None Declared