Is Dietary Protein Intake Predictive of 1-Year Mortality in Dialysis Patients?

Background: High mortality in dialysis patients may be associated with protein-energy wasting (PEW) syndrome characterized by progressively depleted protein and energy stores. While early diagnosis and treatment of PEW can reduce mortality, clinically practical measures for its detection are lacking. Poor dietary protein intake (DPI) is associated with risk of malnutrition and PEW. However, the impact of DPI on mortality is unclear. The purpose of this study is to examine the ability of DPI to predict 1-year mortality in dialysis patients. Methods: This prospective, secondary study using data from the Comprehensive Dialysis Study and United States Renal Data System examined risk factors associated with 1-year mortality in dialysis patients. Results: Seventeen (7.5%) of the 227 subjects died within 1 year following baseline data collection. One year survivors were significantly younger (60 ± 13.6 versus 71 ± 12.8; P = 0.0043), had a lower Charlson Comorbidity Index score (1.6 ± 2.3 versus 4.0 ± 3.6; P = 0.0157), higher serum albumin level (3.5 ± 0.5 versus 3.3 ± 0.4; P = 0.0173) and had higher DPI (63 ± 33.7 versus 49.5 ± 21.5 g/day; P = 0.0386) than those who died. In multivariable Cox proportional hazards model analyses, only the Charlson Comorbidity Index adjusted hazard ratio for death (1.24) was significantly associated with increased mortality. The Comprehensive Dialysis Study data showed no association between DPI and 1-year mortality in dialysis patients. Conclusions: Future studies using more precise measures should further examine the impact of DPI on mortality given the known association of DPI with PEW syndrome and the definitive link between PEW syndrome and survival in dialysis patients.