Cardiovascular risk assessment in hemodialysis patients: relation to malnutrition, inflammation, and body fluid determined by bioelectrical impedance

Abstract

Background Cardiovascular disease prevalence increases as the renal function declines across the spectrum of chronic kidney disease. In end-stage renal disease (ESRD), cardiovascular mortality may even account for 50% of mortality. The coexistence of malnutrition, inflammation, and atherosclerosis (the so-called MIA syndrome) has been observed in hemodialysis (HD) patients and is considered one of the cardiovascular risk factors unique to this population. In addition, chronic fluid overload is frequently present in HD patients. Objective The aim of the present study was to investigate the relationship between nutrition, inflammation, atherosclerosis, the presence of overhydration (OH) measured using multifrequency bioimpedance analysis, and the cardiac condition as assessed using echocardiography in HD patients. Patients and methods Thirty HD patients (mean age: 41.13±12.77 years, 15 were male and 15 were female) were enrolled in the Dialysis Unit of the Alexandria Main University Hospital. Serum albumin was used as a nutritional marker, and serum C-reactive protein (CRP) was used as an inflammatory marker. Doppler ultrasonography was performed to measure the carotid artery intimamedia thickness (CA-IMT) to assess the presence of atherosclerosis. Extracellular water (ECW), OH, and OH/ECW were measured using multifrequency bioimpedance analysis to detect OH. Cardiac condition was determined by means of echocardiographic measurement of the left ventricular mass index and ejection fraction (EF). Results Only two (6.6%) of the studied patients had a low albumin, 26 (86.6%) patients had a positive CRP, 23 (76.6%) patients had high carotid intimamedia thickness (CIMT), and nine (30%) patients had atherosclerotic plaques in the carotid artery. Bioimpedance showed OH in 15 (50%) patients, who had an OH/ECW ratio of more than 0.15. Echocardiography showed high left ventricular mass index in 55.5% and low EF in 16.6%. The presence of inflammation as indicated by CRP was associated with higher CIMT (r=0.520, P=0.003), higher interventricular wall thickness (IVWT) (r=0.469, P=0.007), and lower EF (r=−0.610, P Conclusion Inflammation, atherosclerosis, and fluid overload are prevalent in ESRD patients on MHD. Both inflammation and OH are correlated with increased CIMT and low EF, implicating them in the cardiovascular diseases commonly found in ESRD patients.