Ratio of extracellular water to intracellular water and simplified creatinine index as predictors of all-cause mortality for patients receiving hemodialysis

Abstract

The bioelectrical impedance analysis-measured ratio of extracellular water (ECW) to intracellular water (ICW) reflects fluid volume and malnutrition. It may be an indicator of protein-energy wasting and muscle wasting in hemodialysis patients. We examined the association between the ECW/ICW ratio and simplified creatinine index, which is a new surrogate marker of protein-energy wasting and muscle wasting, and whether their combination can accurately predict mortality. A total of 224 patients undergoing hemodialysis for more than 6 months and having undergone bioelectrical impedance analysis for the assessment of body composition were included. Patients were divided into two groups based on the cut-off values of the ECW/ICW ratio (0.57) and simplified creatinine index (20.4 mg/kg/day) for maximumly predicting mortality. Thereafter, they were cross-classified into four groups with each cut-off point. The ECW/ICW ratio was independently associated with the simplified creatinine index (β = -0.164; P = 0.042). During a follow-up of 3.5 years (2.0–6.0 years), 77 patients died. A higher ECW/ICW ratio (adjusted hazard ratio, 3.66, 95% confidence interval 1.99–6.72, P <0.0001) and lower simplified creatinine index (adjusted hazard ratio, 2.25, 95% confidence interval 1.34–3.79, P = 0.0021) were independently associated with an increased risk of all-cause mortality. The adjusted hazard ratio for the higher ECW/ICW ratio and lower simplified creatinine index group vs. the lower ECW/ICW ratio and higher simplified creatinine index group was 12.22 (95% confidence interval 3.68–40.57, p <0.0001). Furthermore, the addition of the ECW/ICW ratio and simplified creatinine index to the baseline risk model significantly improved the C-index from 0.831 to 0.864 (p = 0.045). In conclusion, the ECW/ICW ratio may be a surrogate marker of muscle wasting. Moreover, combining the ECW/ICW ratio and simplified creatinine index may improve the accuracy of predicting all-cause mortality and help stratify the mortality risk of hemodialysis patients.

Tirzepatide Reduces Fat Mass and Provides Good Glycaemic Control in Type 2 Diabetes Patients Undergoing Haemodialysis: A Single‐Centre Retrospective Study

“…Blood samples were obtained with the patients in supine position before and after HD at the beginning of the week. Bioelectrical impedance analysis (BIA) was performed in the supine position approximately 30 min after the HD session, when the DW set by the ultrafiltration rate was reached; intracellular water (ICW), extracellular water (ECW) and total body water (TBW), body fat content, skeletal muscle mass, protein content, bone mineral content, basal metabolism and skeletal muscle mass index (SMI) were measured with a body composition meter with multiple frequencies (1 kHz–1 MHz) using the ankle and wrist method [ 11 , 12 ]. The InBody S10 (Biospace Co., Ltd., Seoul, Republic of Korea) was used for measurements.…”

“…were measured with a body composition meter with multiple frequencies (1 kHz-1 MHz) using the ankle and wrist method [11,12]. The InBody S10 (Biospace Co., Ltd., Seoul, Republic of Korea) was used for measurements.…”

“…However, the risk of ESRD persists despite the efficacy of these agents. Consequently, a significant optimism surrounds tirzepatide, a novel incretin‐based therapeutic agent, for its potential in treating DKD [ 10 , 11 ].…”

Muscle Mass and Serum Creatinine Concentration by Race and Ethnicity among Hemodialysis Patients

“…21–27 Previous studies have shown direct correlation between ICW and serum creatinine concentration. 28–31…”

Nutritional Assessments by Bioimpedance Technique in Dialysis Patients

“…Recently, there has been growing interest in using the ratio of ECW to ICW (ECW/ICW) as a composite index of fluid overload and malnutrition. Yajima et al showed that the ECW/ICW (when measured by MF-BIA) was negatively associated with a simplified creatinine index (a surrogate for muscle mass) in 224 prevalent HD patients [ 87 ]. Moreover, both ECW/ICW (≥0.57) and s simplified creatinine index (<20.4 g/kg/day) were independent predictors of all-cause mortality, and this is after the adjustment of demographics, comorbidities, and albumin levels.…”