Assessment of endothelial function by flow-mediated dilation in well-controlled patients with rheumatoid arthritis

Objective: Endothelial dysfunction is considered as the primary pathophysiological process towards the development of cardiovascular disease (CVD). Patients with rheumatoid arthritis (RA) are at increased CVD risk attributed to the synergistic effect of chronic inflammation and traditional cardiovascular risk factors. However, it is uncertain whether endothelial function in RA is impaired even in the absence of cardiovascular comorbidities and pronounced inflammatory load. Design and method: Patients with RA who presented low levels of systemic inflammation and were free from cardiovascular comorbidities including hypertension, diabetes mellitus and established CVD, were studied. Non-RA individuals matched for age, sex and office systolic/diastolic blood pressure comprised the control group. Endothelial function was evaluated with the gold-standard flow-mediated dilation (FMD) in the brachial artery (Aloka ProSound A7 Ultrasound System). Results: A total of 22 female individuals were included in the study, of whom 10 were RA patients aged 57±13 years and 12 healthy volunteers aged 56±9 years. All patients with RA were at remission or low disease activity. Traditional CVD risk factors (age, systolic and diastolic blood pressure, smoking, body mass index and lipids) did not significantly differ between RA patients and controls. By contrast, significantly lower FMD values were observed in the RA group compared to controls [6.4 (5.0) vs 11.8 (5.2) %, p = 0.003]. The association between RA and FMD levels remained significant even after adjustment for age and systolic blood pressure (beta = 0.562, p = 0.009). Conclusions: Endothelial dysfunction is present in RA, even in a population characterized by the absence of hypertension and cardiovascular comorbidities and with relatively low systemic inflammatory burden. Further studies are warranted to verify the findings of this pilot study and delineate the role of endothelial dysfunction as a potential prognostic marker or therapeutic target.