Effect of hypertension on microcirculatory disorders in patients with rheumatoid arthritis

Abstract

Introduction. The presence of endothelial dysfunction contributes to the progression of rheumatoid arthritis (RA) and the development of cardiovascular diseases. However, microcirculatory signs in the combination of RA with hypertension have not been studied enough.Objective – to clarify the contribution of concomitant hypertension in the formation of microcirculatory disorders in patients with RA.Materials and methods. The observational study involved 123 patients of both sexes from 18 to 72 years old (103 – the study group with verified RA, 23 – the control group, representing relatively healthy volunteers). Hypertension occurred in 55.3 % of patients. Laser Doppler flowmetry was performed to assess vasomotor function. Both the initial perfusion parameters were studied with the calculation of the amplitude-frequency spectrum, as well as an occlusive test and a test with acetylcholine iontophoresis. Initial perfusion parameters were studied with time– frequency analysis, an arterial occlusion test and an acetylcholine iontophoresis test were performed.Results. Patients with concomitant hypertension against the background of RA had a more pronounced decrease in the amplitudes of the endothelial (p=0.036) and neurogenic (NC) (p=0.005) components of the spectrum, an increase in respiratory modulation (RM) (p=0.002), as well as a decrease in the reserve of capillary blood flow (p=0.010) and shortened time to perfusion half-restoration (p=0.042) in the occlusion test. However, there were no significant differences between the groups in terms of the acetylcholine iontophoresis test (p≥0.05). The relationship between the RM amplitude and cardiovascular risk (CVR) was established according to the SCORE (ρ=0.269; p=0.022), as well as with systolic (ρ=0.324; p=0.005) and diastolic (ρ=0.234; p=0.045) blood pressure was established. An assessment of the RM amplitude predicted the presence of concomitant hypertension with a sensitivity of 72.5 % and a specificity of 75 % (p=0.001).Conclusion. The presence of concomitant hypertension against the background of RA was associated with more pronounced vasomotor dysfunction, as well as with the presence of venular hypertension (VH), which is the pathogenetic link of hypertension. At the same time, an increase in the amplitude of the RM, which reflects VH, allows it to be used as an early additional prognostic marker for the presence of concomitant hypertension and increased CVR in patients with RA.