A composite score of protein-energy nutritional status predicts mortality in haemodialysis patients no better than its individual components.
BACKGROUND
Protein-energy wasting is tightly associated with mortality in haemodialysis patients. An expert panel of the International Society of Renal Nutrition and Metabolism (ISRNM) has published a consensus on the parameters that define protein-energy nutritional status and posed the question, 'which scoring system most effectively predicts outcome?' The aim of our study was therefore to develop a composite score of protein-energy nutritional status (cPENS) and to assess its prediction of all-cause mortality.


METHODS
We used the data of 560 haemodialysis patients participating in the CONvective TRAnsport STudy (CONTRAST). All participants were followed for occurrence of death. Internationally recommended nutritional targets were used as components of the cPENS, including the subjective global assessment (target score ≥ 6), albumin (≥ 4.0 g/dL), normalized protein nitrogen appearance (≥ 0.8 g/kg/day), cholesterol (≥ 100 mg/dL), creatinine (≥ 10 mg/dL) and BMI (> 23 kg/m(2)). A Cox regression model was used to analyse the relation between different cPENS variants and mortality.


RESULTS
The median follow-up time was 1.4 years (max 4.2). One hundred and five patients (19%) died. A cPENS variant based on albumin, BMI, creatinine and the nPNA yielded the strongest relation with mortality (hazard ratio 0.63, 95% confidence interval 0.54-0.74, P < 0.001), after adjustments for confounders. Some of the individual parameters of the cPENS, notably albumin and creatinine, were related to mortality with similar strength and magnitude.


CONCLUSIONS
In conclusion, albumin reflects mortality risk similarly to multiple nutritional parameters combined. This questions the clinical value of the proposed diagnostic criteria for protein-energy wasting.
Department of Nephrology, University Medical Center Utrecht, Utrecht, The Netherlands.
Albert H A
AH
Mazairac
G Ardine
GA
de Wit
Muriel P C
MP
Grooteman
E Lars
EL
Penne
Neelke C
NC
van der Weerd
Marinus A
MA
van den Dorpel
Menso J
MJ
Nubé
Renée
R
Lévesque
Piet M
PM
Ter Wee
Michiel L
ML
Bots
Peter J
PJ
Blankestijn
D000368:Aged; D000418:Albumins / Q000032:analysis*; D015331:Cohort Studies; D003404:Creatinine / Q000032:analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000401:mortality* / Q000628:therapy; D008297:Male; D044342:Malnutrition / Q000145:classification* / Q000175:diagnosis / Q000209:etiology; D008875:Middle Aged; D009752:Nutritional Status; D011379:Prognosis; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects / Q000401:mortality*; D015996:Survival Rate; D019282:Wasting Syndrome / Q000145:classification* / Q000175:diagnosis / Q000209:etiology
D000418:Albumins; D003404:Creatinine