The association of overhydration with chronic inflammation in chronic maintenance hemodiafiltration patients

Abstract

Introduction: Achieving euvolemia is one of the major challenges when treating end‐stage renal disease (ESRD) patients receiving maintenance renal replacement therapy. Fluid overload is recognized as an independent predictor of mortality in ESRD, but its association with chronic inflammation is less well explored especially in chronic maintenance hemodiafiltration. Methods: We performed a cross‐sectional study of 87 prevalent ESRD patients receiving chronic maintenance hemodiafiltration (vintage 66.5 ± 57.1 months) with bioimpedance analysis to characterize the degree of percent overhydration (OH%). We also compared the levels of inflammatory markers, including C‐reactive protein (CRP), serum albumin, neutrophil/lymphocyte ratio (NLR), and hemoglobin red cell distribution width (RDW) for the overhydrated (OH% ≥ 15%) versus euvolemic (OH% < 15%) groups. Linear regression analysis was performed to explore relationships between the degree of OH and inflammatory indicators. Findings: The cohort represented an all‐European population with a mean age of 60.9 ± 14.7 years and prevalence of diabetes mellitus of 27%. The entire cohort's OH% was 14.9% ± 5.1% (range −11.1% to 39.0%); further, the <15% group of patients’ OH% was 8.0% ± 8.5% versus 20.9% ± 5.1% in the OH% ≥ 15% group (P < 0.0001). Forty‐seven patients (53%) were overhydrated by traditional criteria (OH% ≥15%) and 20 patients (23%) were severely overhydrated (OH% > 20%). The euvolemic (OH% <15%) versus severely overhydrated (OH% > 20%) groups had significant differences in markers of inflammation: CRP (9.8 ± 10.6 vs. 21.5 ± 21.6 mg/L, P < 0.006), serum albumin (37.6 ± 02.9 vs. 34.5 ± 5.3 g/L, P < 0.004), and NLR (3.06 ± 1.25 vs. 3.92 ± 2.04; P < 0.004). On linear regression, significant correlations were found between OH% and CRP (r = 0.2899, P < 0.006), serum albumin (r = −0.3670; P < 0.0005), RDW (r = 0.2992; P < 0.005), and NLR (r = 0.2900; P < 0.006). Discussion: In a prevalent hemodiafiltration cohort, OH was common and correlated with several inflammatory markers.

Subjective global assessment of nutrition, dialysis quality, and the theory of the scientific method in Nephrology practice

“…Monitoring fluid quality is crucial to ensure that contribution of the hemodialysis procedure to inflammation is minimized. 50 There is no doubt that both markers of inflammation 60,61 and the presence of hypervolemia 11 are strong independent predictors of mortality in dialysis patients. Perhaps this is one of the reasons why MIS index is so robust in predicting mortality: it incorporates variables associated with nutritional status, inflammation, and hypervolemia providing a global marker for these interconnected processes.…”

“…Numerous reports and meta-analyses support the ability of BIS to quantify hypervolemia in dialysis patients 12,[62][63][64] and hypervolemia as determined by BIS has proved to be a strong independent predictor of mortality in the dialysis population. 11,64 As hypervolemia is also correlated with both inflammation, 50 and peritoneal protein loss in PD patients, 65 hypervolemia found on BIS is a strong hint for ongoing inflammation and related malnutrition. 64 The ability of BIS to identify malnutrition is less well documented and there are conflicting results as to the relative strengths of SGA versus BIS to predict mortality in malnourished patients, some authors finding BIS 66 while most others SGA 20,22 to be the more accurate.…”

“…Hypervolemia is a vexing problem in chronic kidney disease patients not only due to its well-known effect on blood pressure control but also because of its close relationship with systemic inflammation and intestinal dysbiosis. [50][51][52][53] Hypervolemia on dialysis is rampant affecting as many as 30%-95% of chronic maintenance hemodialysis or hemodiafiltration patients. 50,[100][101][102] Hypervolemia, 11,100 ultrafiltration rate 103 and intradialytic hypotension 104 have all been correlated with mortality.…”

Indoxyl sulfate and high-density lipoprotein cholesterol in early stages of chronic kidney disease

“…Indoxyl sulfate (IS), a protein-bound uremic toxin, is one of the organic anions that results from the metabolism of dietary tryptophan and after intestinal absorption is further converted to IS in the liver [2]. Microbiome and intestinal permeability changes induced by hypervolemia may lead to increased IS, inflammation and endothelial dysfunction [3,4]. IS is excreted via proximal tubular secretion in the kidney and it accumulates in the blood of patients with declined renal function.…”

Influence of dry weight reduction on anemia in patients undergoing hemodialysis

“…Of these markers, CRP has shown relatively high specificity and correlation with hypervolemia, showing a positive correlation with the degree of inflammation but a negative correlation with serum albumin and Hb levels. 13–17…”