Relationship Between Malnutrition and Lipid Levels in End-Stag Renal Disease Patients

Purpose

Serum albumin is the most prevalent protein in the blood and is a routine measure of nutritional status in End-Stage Renal Disease (ESRD) patients. Many studies have demonstrated that low albumin levels (< 3.5 mg/dL) are associated with higher risk of mortality and morbidity in ESRD patients. Yet, little is know about the effects of albumin levels on lipid values. Therefore, this study measured the effects of malnutrition and metabolic risk factors for cardiovascular disease in 39 ESRD patients. Methods

This study was a cross-sectional investigation of ESRD patients. Participants were placed into a microalbumin group (<3.5 mg/dL) or an albumin group (>3.5 mg/dL) to discover if significant differences existed in lipid values (specifically subclasses of low-density lipoprotein cholesterol [LDL] and very low-density lipoprotein cholesterol [VLDL]) between groups. LDL and VLDL particle size was measured by nuclear magnetic resonance (NMR) with LDL measured by gel electrophoresis.

Analysis/Results

LDL was significantly higher in the microalbumin group (p=.032). The microalbumin group had less of the smaller dense LDL particles (LDL particle size [p=.020]) and more large VLDL particles (p=.016). A significant moderate Pearson correlation existed between albumin level and LDL (r2=.537, p=.032) and LDL particle size and albumin level (r2=.765, p=.016).

Conclusions

Microalbuminuria in this study was associated with an increased risk for cardiovascular disease due to elevated levels of LDL, but was associated with a “reverse epidemiology” effect of less small, dense, atherogenic VLDL particles. ESRD patients who undergo chronic hemodialysis have nutritional deficiencies and recent studies have suggested a reverse epidemiological effect that may be a function of nutritional status and may not necessarily be associated with a decrease in cardiovascular risk. It has been postulated that these nutritional deficiencies may be responsible for larger, less dense LDL and VLDL particles, but still would be associated with increased risk for disease. The present study partially supports this hypothesis in that LDL and VLDL size was larger (less risk) in the microalbumin group, but lower albumin levels were also associated with increased risk through an elevated LDL level. This may be due to a VLDL defect that occurs in ESRD patients which would have downstream effects on VLDL particle size and LDL particle size. Future studies will need to ascertain whether the decreased risk with lipid values would be offset by the lower albumin levels that are associated with higher levels of mortality and morbidity.