Features of disorders of uric acid metabolism in male patients with hypertension and atrial fibrillation

Abstract

Abstract Background In recent decades, a significant number of epidemiological studies showed the association between asymptomatic hyperuricemia and development of arterial hypertension (HTN) and atrial fibrillation (AF). The key enzyme participating in disintegration purines to uric acid is xanthine oxidase (XO). The accumulated data suggest the existence of a direct pathophysiological role of increased level of serum uric acid (SUA) and XO activity with a risk of HTN and AF. Purpose To evaluate the features of disorders of UA metabolism in patients with HTN and AF. Materials and methods The study included male patients 27 to 65 years, with a body mass index (BMI) less than 30 kg/m2 and more than 18.5 kg/m2. All patients were investigated of the level of a SUA, hypoxanthine/xanthine, inosine/adenosine, XO enzyme activity. Depending on the presence of AF, all patients were divided into 2 groups: group 1 (n=16) patients with HTN, group 2 (n=16) patients with HTN and AF. Results Table 1 shows the indicators of purine metabolism in the compared groups. The analysis of the results demonstrates that in group 1 the smallest level of a SUA in comparison with group 2 (0.35 [0.31; 0.41] vs 0.41 [0.39; 0.40](μmol/l), p=0.003), hypoxanthine 3.02 [1.80; 5.63] vs 7.35 [4.56; 8.25](μmol/l), p=0.008; inosine 1.59 [1.25; 4.48] vs 7.41 [1.49; 17.24](μmol/l), p=0.002. An increase level of a SUA is noted in 31.2% of patients from group 1 (5 patients out of 16) and 68.7% of patients from group 2 (11 patients out of 16). As a result of Spearman's correlation analysis in the group of patients with HTN and AF, a direct correlation was found between the experience of AF and BMI (r=0.681), SBP (r=0.487); level of hypoxanthine and inosine (r=0.808) and the inverse correlation between the level of xanthine and inosine (r=−0.547), as well as the association between the level of XO and SUA (r=0.796), XO and BMI (r=0.812). In the group of patients with HTN was determined association between the level of hypoxanthine and inosine (r=0.604), xanthine and adenosine (r=0.539), inosine and adenosine (r=0.657), a direct association between the level of XO and adenosine (r=0.642), inosine (r=0.502), BMI (r=0.791). Conclusions As a result of the study of patients with isolated HTN in combination with AF at the age of 27 to 65 years and a BMI of less than 30 kg/m2 and more than 18.5 kg/m2, an increase level of SUA and intermediate metabolites of UA synthesis such as inosine and hypoxanthine is observed compared with group with isolated HTN. An increase in level of XO is associated with an increase level of SUA and BMI. In the group of patients with HTN, an increase in level of inosine is associated with an increase level of hypoxanthine, but an increased level of inosine is associated with a decrease in level of xanthine. The XO level in this group is associated with an increase in level of adenosine and inosine, BMI. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Grodno State Medical University, Grodno, Belarus Table 1. Comparative characteristics of indicators in groups 1 and 2