The influence of obesity on the course and development of complications of chronic kidney disease according to the study of the blood and urine uromodulin

Abstract

Background. Obesity has a significant impact on the course of chronic kidney disease (CKD), as it contributes to the occurrence of oxidative stress, inflammation and activation of the renin-angiotensin-aldosterone system. The mechanisms of obesity influence on CKD are not fully understood. A new approach is needed to assess obesity status in patients with CKD. The purpose of the study: to investigate the relationship between overweight or obesity in patients with CKD stage I–III and the course and development of CKD complications depending on uromodulin levels. Materials and methods. A prospective randomized cohort study ROLUNT (uROmoduLin, UbiquinoNe, glutaThione), in which 123 patients participated in 2021–2023. It was conducted at ­VETA-PLUS LLC, Professor Dmytro Ivanov Nephrology Clinic LLC and CDC of Brovary Multidisciplinary Clinical Hospital, which are the clinical bases of the Department of Nephrology and Renal Replacement Therapy of the Shupyk National Healthcare University of Ukraine. Participants were divided into 3 groups: group 1 (n = 21) — patients with CKD stage I–III and body mass index (BMI) < 25 kg/m2, group 2 (n = 58) — those with CKD stage I–III and BMI of 25–29.9 kg/m2, and group 3 (n = 44) — patients with CKD I–III stage and BMI > 30 kg/m2. Results. The average age of participants is 49–50 years, there were 44 men (35.77 %), 79 women (64.23 %). All groups had no statistically significant differences in age and gender. In the structure of CKD, the most common pathology was tubulointerstitial nephritis of unknown etiology — 27 patients (29.67 %). During kidney ultrasound, a significant share belonged to urinary salt diathesis — in 55 patients (44.72 %). The median BMI in groups 1, 2, and 3 were 22.1, 27.6, and 32.9 kg/m2, respectively. The average values of urinary uromodulin (uUmod), daily excretion of uromodulin (uUmod24), urinary albumin (uAlb), serum uromodulin (sUmod) for group 1 are 25.06, 56.18, 17.95, 47.22, respectively, the median values of these indicators for groups 2 and 3 are 26.2 and 26.15; 57 and 53.75; 26.7 and 28.55; 47.65 and 49.4, respectively. Correlation analysis in group 1 revealed statistically significant strong direct relathionship between uUmod and uUmod24, uUmod/sUmod, uUmod24 and uUmod, uUmod/sUmod, uUmod/estimated glomerular filtration rate (eGFR), sUmod and uUmod/eGFR. Correlation analysis in group 2 demonstrated a statistically significant strong direct relationship between uUmod24 and uUmod/eGFR, uUmod and sUmod, eGFR. Correlation analysis in group 3 revealed a statistically significant strong direct relationship between uUmod and uUmod/sUmod, uUmod24 and uUmod/eGFR. Conclusions. Statistical analysis showed that in all 3 groups, uUmod has a significant direct strong correlation with the uUmod/sUmod concentration index. In all 3 groups, uUmod24 has a significant direct strong correlation with the uUmod/eGFR index. But only in group 2, there is a significant strong direct correlation between uUmod and eGFR and a significant strong inverse correlation between uUmod and uAlb/urinary creatinine, fractional excretion of uromodulin, serum urea, urea nitrogen, serum creatinine.