Possibilities of using determination of allelic polymorphism of interleukin-6 G174C and tumour necrosis factor-α G308A genes for the prediction of cardiovascular disorders in children with juvenile idiopathic arthritis

Abstract

Objectives: Juvenile idiopathic arthritis is a chronic disease that affects the synovial membrane of the joints, but can also lead to secondary lesions of the cardiovascular system. The most important mechanism of myocardial damage is associated with the effect of proinflammatory cytokines. The aim of the study was to propose a method of early detection of cardiovascular system changes and lesions in patients with juvenile idiopathic arthritis based on the determination of allelic polymorphism combined with electrocardiography data. Materials and methods: 102 patients with juvenile idiopathic arthritis underwent a general clinical examination. The overall activity of juvenile idiopathic arthritis was assessed using the Juvenile Arthritis Disease Activity Score. In addition, the patients underwent an electrocardiographic evaluation using the software and hardware complex “Cardioplus P,” which is a portable electrocardiograph providing “signal-averaged” electrocardiography performing the recognition and measurement of amplitude-time parameters, and calculation of secondary electrocardiography parameters. The genotypes of patients were additionally determined by alleles of the TNF-α (G308A) and IL6 (G174C) genes by polymerase chain reaction. Results: The overall number of mutations affects the course of the disease, with two or more mutations being associated with a more aggressive course of the disease, a more pronounced degree of inflammation, and a higher frequency of extra-articular lesions. The complex indicator of the functional state of the myocardium according to the electrocardiography data differed significantly (p = 0.00001) in clusters. Conclusion: Patients with juvenile idiopathic arthritis with two or more mutations in different genes of proinflammatory cytokines have a higher activity of the inflammatory process and a higher frequency of cardiovascular changes according to 4th generation electrocardiography. The determination of polymorphism may be useful in evaluating the risk of development of cardiovascular system abnormalities.