The relationship between serum uric acid level and 24 HOUR blood pressure variability in NON-diabetic patients with chronic kidney disease

Aim: It is known that blood pressure variability is associated with target organ damage and cardiovascular mortality independent of blood pressure level in hypertensive patients. Although hyperuricemia is known as an independent risk factor for the development of hypertension, its effect on blood pressure variability has not yet been clarified. Therefore, the effect of serum uric acid levels on blood pressure variability was investigated in patients with chronic kidney disease. Materials and Methods: The study started after obtaining local ethics committee approval (date and no: 07.07.2021-482). Ninety patients with stage 2-4 chronic kidney disease were included in the study. Serum uric acid level was measured by the colorimetric method. Blood pressure measurements were taken every 15 minutes during the day and every 30 minutes during the night using an ambulatory blood pressure monitoring device attached to the patients. The average real variability value, which shows the blood pressure variability using mathematical measurements, was obtained from 24-hour blood pressure measurements (systolic, diastolic, and mean arterial pressure). The correlation between serum uric acid levels and average real variability was evaluated. Results: A positive correlation was found between serum uric acid level and 24-hour systolic average real variability, 24-hour diastolic average real variability, and 24-hour mean arterial pressure average real variability values (p= 0.012, p= 0.041, p= 0.044, respectively). No significant difference was found between serum uric acid levels and blood pressure variability according to chronic kidney disease stages. A positive correlation was found between age and 24-hour mean arterial pressure average real variability, night mean arterial pressure average real variability, and night systolic average real variability values (p= 0.030, p= 0.001, p= 0.003, respectively). A positive correlation was found between 24-hour systolic average real variability, 24-hour night mean arterial pressure average real variability, and night systolic average real variability values and body mass index (p= 0.032, p= 0.045, p= 0.014, respectively). A positive VIII correlation was found between hypertension duration and all average real variability values (p< 0.001). Conclusion: A positive correlation was found between serum uric acid levels and 24- hour systolic average real variability, 24-hour diastolic average real variability, and 24- hour mean arterial pressure average real variability values. In light of these results, it was considered that hyperuricemia may contribute to an increase in blood pressure variability in those with chronic kidney disease. Keywords: Hypertension, Blood Pressure Variability, Chronic Kidney Disease, Serum Uric Acid