Arterial Stiffness, Malnutrition and Inflammation in Chronic Hemodialysis Patients

Joo, Min Ha; Koo, Ja Ryong; Yoon, Jong Yoo; Han, Sang Jin; Song, Young Lim; Song, Soo Jin; Song, Young Soo; Kim, Seong Gyun; Oh, Ji Eun; Lee, Young Ki; Seo, Jang Won; Kim, Hyung Jik; Noh, Jung Woo

Abstract

BACKGROUND: In ESRD patients, malnutrition and atherosclerosis are strongly associated with inflammation resulting in MIA (Malnutrition-Inflammation-Atherosclerosis) syndrome. As compared with atherosclerosis, arteriosclerosis or arterial stiffening is another important cardiovascular risk factor. Therefore, we speculated on the presence of new MIA syndrome, which is composed of malnutrition, inflammation and arteriosclerosis, and evaluated causal relations among them in 70 chronic hemodialysis patients (age 53+/-13 years, male 53%, diabetes 40%).
METHODS
As an indicator of arterial stiffness, brachial-ankle pulse wave velocity (PWV) was measured using a plethysmography. PWV index (measured PWV/nomogram based theoretical PWV) was then calculated to adjust confounding effects of age, blood pressure, and gender by using the PWV nomogram obtained in nonuremic population with same age, blood pressure, and gender. Nutritional status was assessed by serum albumin level, subjective global assessment (SGA) and normalized protein catabolic rate (nPCR). Extracellular fluid and intracellular fluid volume ratio (ECF/ICF) were determined using bioimpedance analysis. The presence of an inflammation was assessed by serum high sensitivity C-reactive protein (CRP) level.
RESULTS
PWV index correlated positively with log transformed CRP (LnCRP) level, ECF/ICF and negatively with SGA, nPCR and serum albumin level. Serum albumin level correlated positively with nPCR, BUN, hemoglobin level and negatively with LnCRP level, age and ECF/ICF. Diabetic patients had higher PWV index and lower albumin level than non-diabetic patients. In multiple regression analysis, only LnCRP level was a significant common determinant of the both PWV index (R2=0.419; p >0.001) and serum albumin level (R2=0.543; p<0.001).
CONCLUSION
Increased CRP levels are independently associated with arterial stiffening and hypoalbuminemia. Inflammation might be a linking mechanism of arterial stiffening and malnutrition in chronic hemodialysis patients.