Malnutrition and Atherosclerosis in Dialysis Patients

Abstract

Longitudinal associations of malnutrition with atherosclerotic events in uremia are unclear. In 50,732 incident Medicare dialysis patients who had normal (18.5 to 24.9 kg/m2), low (<18.5 kg/m2), or high (≥ 25 kg/m2) body mass index (BMI) and initiated dialysis in the United States from January 1995 to December 1999 with reported measured creatinine clearances and acute coronary syndrome (ACS; International Classification of Diseases, Ninth Revision codes 410.x and 411.x) were examined in parametric survival models. Normal BMI was the referent group. Twenty-four-hour urinary creatinine (UCr) was used as a measure of muscle mass. There were 7213 (14.2%) hospitalized ACS events, 1528 (22%) of which were fatal (death within 30 d). One-year post-ACS mortality was 48%. Low BMI (hazard ratio [HR], 0.89; P = 0.02] was associated with lower hazard, and UCr was not predictive (NS) of hospitalized ACS in multivariable model. Low BMI (NS) was not associated with a composite end point of hospitalized ACS/suspected out-of-hospital ACS death, whereas lowest UCr quartile was associated with higher hazard (HR, 1.14; P < 0.001). Low BMI (HR, 1.24; P < 0.001) and decrease in UCr (highest quartile reference, second quartile HR, 1.11 [P < 0.001]; third quartile HR, 1.24 [P < 0.001]; and fourth quartile HR, 1.43 [P < 0.001]) were associated with increased hazard of death. Hospitalized ACS events in dialysis patients carry very high immediate and long-term mortality. Positive longitudinal associations of malnutrition with documented hospitalized ACS events could not be demonstrated. Further longitudinal studies are warranted to provide definitive evidence of malnutrition as a uremic risk factor for atherosclerosis.