title: Low protein nitrogen appearance as a surrogate of low dietary protein intake is associated with higher all-cause mortality in maintenance hemodialysis patients.
abstract: To determine the association between all-cause mortality and dietary protein intake in patients with chronic kidney disease, we performed a large-scale, 8-y prospective cohort study in 98,489 maintenance hemodialysis patients from a multicenter dialysis care provider. Compared with the reference level (60 to <70 g/d), low protein nitrogen appearance (PNA) levels [<30 g/d, HR: 1.40 (95% CI: 1.30, 1.50); 30 to <40 g/d, HR: 1.33 (95% CI: 1.28, 1.39)] was associated with higher all-cause mortality, and high PNA levels [≥110 g/d, HR: 0.92 (95% CI: 0.88, 0.97); 100 to <110 g/d, HR: 0.87 (95% CI: 0.82, 0.91)] were associated with lower all-cause mortality in all analyses. This association was also found in subanalyses performed among racial and hypoalbuminemic groups. Hence, using PNA as a surrogate for protein intake, a low daily dietary protein intake is associated with increased risk of death in all hemodialysis patients. Whether the association between dietary protein intake and survival is causal or a consequence of anorexia secondary to protein-energy-wasting/inflammation or other factors should be explored in interventional trials.
authors.affiliation: Harold Simmons Center for Chronic Disease Research & Epidemiology, University of California Irvine Medical Center, Irvine, CA, USA.
authors.forename: Vanessa A
authors.initials: VA
authors.lastname: Ravel
authors.forename: Miklos Z
authors.initials: MZ
authors.lastname: Molnar
authors.forename: Elani
authors.initials: E
authors.lastname: Streja
authors.forename: Jun Chul
authors.initials: JC
authors.lastname: Kim
authors.forename: Alla
authors.initials: A
authors.lastname: Victoroff
authors.forename: Jennie
authors.initials: J
authors.lastname: Jing
authors.forename: Debbie
authors.initials: D
authors.lastname: Benner
authors.forename: Keith C
authors.initials: KC
authors.lastname: Norris
authors.forename: Csaba P
authors.initials: CP
authors.lastname: Kovesdy
authors.forename: Joel D
authors.initials: JD
authors.lastname: Kopple
authors.forename: Kamyar
authors.initials: K
authors.lastname: Kalantar-Zadeh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D018753:Diet, Protein-Restricted; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007249:Inflammation / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000008:administration & dosage*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis / Q000401:mortality*; D051436:Renal Insufficiency, Chronic / Q000178:diet therapy / Q000401:mortality; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D004044:Dietary Proteins; D009584:Nitrogen