Fluid overload in hemodialysis patients: a cross-sectional study to determine its association with cardiac biomarkers and nutritional status

Abstract

BackgroundChronic fluid overload is associated with higher mortality in dialysis patients; however, the link with cardiovascular morbidity has not formally been established and may be influenced by subclinical inflammation. We hypothesized that a relationship exists between fluid overload and [i] cardiovascular laboratory parameter as well as between fluid overload and [ii] inflammatory laboratory parameters. In addition, we aimed to confirm whether volume status correlates with nutritional status.MethodsWe recorded baseline characteristics of 244 hemodialysis patients at three hemodialysis facilities in Vienna (Austria) and determined associations with volume measurements using the body composition monitor (Fresenius/Germany). In one facility comprising 126 patients, we further analyzed cardiovascular, inflammatory and nutritional parameters.ResultsWe detected predialysis fluid overload (FO) in 39% of all patients (n = 95) with FO defined as ≥15% of extracellular water (ECW). In this subgroup, the absolute FO was 4.4 +/-1.5 L or 22.9 ± 4.8% of ECW. A sub-analysis of patients from one center showed that FO was negatively associated with body mass index (r = -0.371; p = <0.001), while serum albumin was significantly lower in fluid overloaded patients (p = 0.001). FO was positively associated with D-Dimer (r = 0.316; p = 0.001), troponin T (r = 0.325; p < 0.001), and N-terminal pro-B-type natriuretic peptide (r = 0.436; p < 0.001), but not with investigated inflammatory parameters.ConclusionsFluid overload in HD patients was found to be lower in patients with high body mass index, indicating that dry weight was inadequately prescribed and/or difficult to achieve in overweight patients. The association with parameters of cardiovascular compromise and/or damage suggests that fluid overload is a biomarker for cardiovascular risk. Future studies should determine if this applies to patients prior to end-stage renal disease.

Methods of nutritional evaluation between patients in hemodialysis

“…Antlanger et al (2013) also observed this association, indicating that the highest percentage of fluid was observed in individuals with less fat, and agreed with a previous study that described fluid overload in patients with low BMI and lower concentrations of albumin 24 . To justify such observations, they postulate that obese patients have a lower accumulation of fluid, due to diuretic or residual kidney function that allows for greater elimination of urine.…”

A Cut off Value for Brain Natriuretic Peptide Indicating Volume Overload in Hemodialysis Patients

“…Concerning laboratory investigations as serum creatinine, urea, uric acid, serum albumin, sodium, potassium and calcium levels, no statistically significant difference was found between hypervolemic and normovolemic dialysis patients. In contrast, Antlanger et al reported that fluid overload is most common in hemodialysis patients with low body mass index and lower serum albumin levels but similar to our results; there was no significant difference between hypervolemic and normovolemic patients regarding gender and age [13].…”

Variables associated with lung congestion as assessed by chest ultrasound in diabetics undergoing hemodialysis

“…Traditional predictors of fluid overload were not validated as variables associated with lung congestion in our study, like lower body mass index, 17,18 less residual urine output, 18 higher systolic blood pressure. 18,19 In our study, the NYHA result (a very simple scoring based on clinical evaluation) and IVC collapse index (a well-known marker of hypervolemia) were associated with lung congestion.…”