Endothelial function in patients with rheumatoid arthritis without classic cardiovascular risk factors is determined by subclinical lipid disturbances and compensatory vascular adaptation.

INTRODUCTION

Endothelial dysfunction has been reported in rheumatoid arthritis (RA) patients without classic cardiovascular risk factors, but findings remain inconsistent.

OBJECTIVES

We aimed to assess whether endothelial function is impaired in RA with moderate inflammatory burden in the absence of established cardiovascular risk factors.

PATIENTS AND

METHODS

This cross‑sectional study was conducted in 64 patients with RA without classic cardiovascular risk factors and 60 healthy age- and sex‑matched controls. Endothelial function was evaluated in the brachial artery by flow‑mediated dilation (FMD), in the peripheral and skin microcirculation by reactive hyperemia (RH) peripheral arterial tonometry, and flow‑mediated skin fluorescence (FMSF), respectively.

RESULTS

There were no significant differences in the endothelial function parameters between the patients with RA and healthy controls. However, the patients with RA had increased median (interquartile range [IQR]) augmentation index of 3 (-9 to 10) vs -6.5 (-16 to 2; P = 0.003) in the controls. As many as 29 patients with RA that displayed lowered FMD (<7%) had higher mean (SD) level of total cholesterol (5.09 [0.85] vs 4.47 [0.77] mmol/l; P = 0.005) and higher mean (SD) level of low‑density lipoprotein cholesterol (LDL‑C; 2.92 [0.86] vs 2.42 [0.75] mmol/l; P = 0.02). Surprisingly, the subgroup with FMD above 7% had higher median (IQR) C‑reactive protein level than the patients with FMD below 7% (1.11 [1-8.46] vs 1 [1-1] mg/l; P = 0.03). Furthermore, microvascular responses measured by FMSF (RH response, %) were augmented in the patients with higher LDL‑C level, as compared with the group of RA individuals with lower LDL‑C level.

CONCLUSIONS

RA, even with a moderate inflammatory burden, may facilitate detrimental effects of lipoproteins on macrovascular endothelial function. Interestingly, compensatory vascular responses were detected that may precede overt vascular dysfunction. Their monitoring may be useful in endothelial‑guided therapy.