Impact of serum albumin and body-mass index on survival in hemodialysis patients

A low body mass index (BMI) and serum albumin are associated with increased risk of mortality in patients with chronic kidney disease (CKD). The purpose of this study was to evaluate BMI and serum albumin as predictors of all-cause and cardiovascular (CV) mortality in hemodialysed (HD) patients. We describe the results of a five-year retrospective observational study with 187 HD patients (54.9 ± 15.6 years old, 54% men, and 46% suffering from diabetes) from RenalCor Clinic in Rio de Janeiro, Brazil. The influence of serum albumin levels and BMI (determined every three months) over all-cause mortality was examined using a Cox model, while the influence of the same factors over CV mortality among all-cause mortality was modeled through a logistic regression. During the five years, 26.7% of the patients died, 62% of which due to CV disease (CVD). Analysis by the Cox model showed that low serum albumin and low BMI were significant predictors of mortality. Patients with higher BMI had a lower hazard of death for all-cause mortality (hazard ratio [HR] = 0.92; P  = 0.035) and a 1 g/l increase in serum albumin was associated with significantly lower hazard of death (hazard ratio = 0.9679; P < 0.001). The highest BMI value (>30 kg/m²) was significantly associated with an increase of odds of CV mortality (odds ratio = 1.22, P = 0.03). We confirm here in a Brazilian cohort of hemodialysis patients that both low BMI (<19 kg/m²) and hypoalbuminemia are strong predictors of death.