The Relationship Between Bioimpedance-Measured Volume and Nutritional Parameters and Mortality in Hemodialysis Patients

OBJECTIVE: Hypervolemia and malnutrition are often undiagnosed risk factors for hemodialysis (HD). Our aim was to investigate the long-term effects of hypervolemia and malnutrition evaluated by bioimpedance spectroscopy (BIS) on survival. (Clinical Trials. Gov Identifier: NCT01468363). MATERIAL and METHODS: A total of 431 Prevalent HD patients were followed for 32.2±14.4 months. The patients underwent BIS measurement, a medical history was obtained, and routine tests were analyzed at the baseline and at the end of the study. Hospitalizations and complications of HD were recorded. RESULTS: The mean age was 59.4±14.6 (10-92) years with a total of 431 (53.6% males) patients of which 125 died. The percentage of diabetics was 47%, erythropoietin use 67%, and diuretic use 40%. Predialysis systolic blood pressure (BP) was 133.4±25.8 and diastolic BP 79.2±12.4 mm Hg. The rate of diabetes, and the number of hospitalizations and blood transfusions were higher in the patients who died. Diastolic BP as a clinical hypervolemia finding, BIS hypervolemia indicator of over hydration (OH), and extracellular water (ECW) were all increased, and fat tissue index as a malnutrition finding was decreased in patients who died. There were significant rates of anemia and hypoalbuminemia in this group as well. The cumulative survival was lower in hypervolemic patients as assessed by relative hydration status OH/ECW. CONCLUSION: Hypervolemia and malnutrition are the long-term mortality indicators in hemodialysis. Early diagnosis and treatment is important. Clinical findings may not be sufficient and laboratory and BIS methods can be used for diagnosis. KEy wORDS: Overhydration, Bioimpedance, Malnutrition, Fat tissue index, Mortality