Original ResearchComparing Tests Assessing Protein-Energy Wasting: Relation With Quality of Life
Introduction
Many end-stage kidney disease patients need lifelong dialysis treatment. Despite continuous developments in dialysis techniques and improving knowledge concerning the uremic syndrome over the last decades,1 not only remains the life expectancy of these patients severely impaired but also is their quality of life (QOL) usually severely negatively affected in comparison to the general population.2, 3 Among others, QOL is influenced by appetite,4 quality of sleep,5 and nutritional status, i.e. protein-energy wasting (PEW).6, 7
The International Society of Renal Nutrition and Metabolism (ISRNM) introduced the term PEW in 2008 to determine the state of decreased bodily protein and energy fuels in chronic kidney disease patients. PEW appears to be highly prevalent among hemodialysis (HD) patients.8, 9 The following diagnostic criteria were proposed for this syndrome: (1) low blood chemistry (albumin, prealbumin, or cholesterol), (2) low or decreasing body mass, (3) low or decreasing muscle mass, and (4) low dietary intake.10 In the absence of a gold standard, however, the debate on how this syndrome should be assessed is ongoing.11, 12 Although randomized interventional trials are awaited, observational studies and experts suggest that patients suffering from PEW may benefit from supplementation of proteins and energy.13, 14, 15 In addition, a recent randomized trial showed that in patients with a low serum albumin concentration, help with patient-specific barriers such as cooking or improvement of nutritional knowledge resulted in increased serum albumin levels.16 Hence, it appears important to find a reliable way to identify PEW in these patients accurately and easily.
The quest for a gold standard has resulted in many clinical scoring lists, tools, and parameters to diagnose malnutrition or PEW. The most widely investigated clinical nutrition-related scoring lists are the 3-point scaled SGA17, 18 as well as its modified successors, such as the 7-point scaled SGA (SGA-7)19 and the Malnutrition Inflammation Score (MIS).20 Other clinical nutrition-related scoring lists that have been proposed to assess PEW include the Geriatric Nutritional Risk Index (GNRI)21 and the composite score on protein-energy nutritional status (cPENS).22 Furthermore, a number of more or less individual parameters have been associated with PEW, such as serum albumin,23 body mass index (BMI),24 and the normalized protein nitrogen appearance (nPNA) rate.25, 26
In short, presently, it is unknown how PEW can be determined best. With respect to mortality, we recently showed that serum albumin and MIS as markers for PEW predict mortality equally well.27 Besides an impaired life expectancy, a consequence of PEW is a decrease in QOL, as has been stated by the ISRNM in 2008.10 As such, it appears justified to assume that a preferred nutrition-related test should correlate with QOL. To contribute a piece of the puzzle in finding the preferred test to assess PEW, various nutrition-related tests are compared in their relation with various domains of QOL in the present study.
Section snippets
Methods
Various cross-sectional analyses were performed using data from the CONvective TRAnsport STudy (CONTRAST, NCT00205556). Details concerning the design and methods of this study are described elsewhere.28, 29 In brief, CONTRAST was a randomized controlled trial primarily evaluating the effect of postdilution online hemodiafiltration compared with low-flux HD on all-cause mortality and cardiovascular events. Seven hundred fourteen patients were enrolled between 2004 and 2010 in 29 dialysis centers
Demographical, Clinical, and Laboratory Characteristics
Baseline patient characteristics of the entire cohort (n = 714) and the investigated cohort (n = 489) are summarized in Table 1. No marked differences between these groups were observed, suggesting this cohort is a representative sample of the CONTRAST cohort. Patients excluded from the present analysis mostly had a missing nPNA value (n = 120) or lacked information on an MIS item (n = 125). In the investigated cohort, mean age was 63.3 ± 13.8 years. The majority was male (60.5%), and more than
Discussion
The present study investigated correlations between 8 well-established nutrition-related tests and QOL. We clearly demonstrated that of these nutrition-related tests, MIS correlates best with QOL. The other 7 tests had either no or an inferior relation with QOL. We know of no previous study comparing various nutrition-related tests using the correlations of these tests with QOL. From this study, 2 important conclusions can be drawn. First, MIS correlates best with QOL. This adds evidence toward
Practical Application
The present study shows that of the 8 investigated nutrition-related tests, MIS clearly correlates best with QOL. Not only did this score correlate with all (13 of 13) domains of QOL, it also has the highest correlation coefficients. This finding may help to identify the preferred test to assess PEW.
Acknowledgments
The authors are grateful to all staff and patients who participated in this project. Furthermore, they would like to thank Isabelle Chapdelaine for her support in the determination of nutrition-related scores.
CONTRAST (NCT00205556) was supported by a grant from the Dutch Kidney Foundation (Nierstichting Nederland, grant C02.2019) and unrestricted grants from Fresenius Medical Care NL, Gambro Lundia AB (Sweden), the Dr. E.E. Twiss Fund, Roche, the Netherlands, the International Society of
References (48)
- et al.
Health-related quality of life among dialysis patients on three continents: the Dialysis Outcomes and Practice Patterns Study
Kidney Int
(2003) - et al.
Appetite and inflammation, nutrition, anemia, and clinical outcome in hemodialysis patients
Am J Clin Nutr
(2004) - et al.
Nutritional status and depression, sleep disorder, and quality of life in hemodialysis patients
J Ren Nutr
(2007) - et al.
Association of Malnutrition-Inflammation Score with quality of life and mortality in hemodialysis patients: a 5-year prospective cohort study
Am J Kidney Dis
(2009) - et al.
A proposed nomenclature and diagnostic criteria for protein-energy wasting in acute and chronic kidney disease
Kidney Int
(2008) - et al.
Subjective Global Assessment in chronic kidney disease: a review
J Ren Nutr
(2004) Nutritional evaluation of patients receiving dialysis for the management of protein-energy wasting: what is old and what is new?
J Ren Nutr
(2013)- et al.
Effects of peridialytic oral supplements on nutritional status and quality of life in chronic hemodialysis patients
J Ren Nutr
(2009) - et al.
Let them eat during dialysis: an overlooked opportunity to improve outcomes in maintenance hemodialysis patients
J Ren Nutr
(2013) - et al.
Improving albumin levels among hemodialysis patients: a community-based randomized controlled trial
Am J Kidney Dis
(2006)
Validity of Subjective Global Assessment as a nutritional marker in end-stage renal disease
Am J Kidney Dis
A malnutrition-inflammation score is correlated with morbidity and mortality in maintenance hemodialysis patients
Am J Kidney Dis
Low protein nitrogen appearance as a surrogate of low dietary protein intake is associated with higher all-cause mortality in maintenance hemodialysis patients
J Nutr
Normalized protein nitrogen appearance is correlated with hospitalization and mortality in hemodialysis patients with Kt/V greater than 1.20
J Ren Nutr
A comparison of 8 nutrition-related tests to predict mortality in hemodialysis patients
J Ren Nutr
Study protocol: a randomized clinical trial of total parenteral nutrition in malnourished surgical patients
Am J Clin Nutr
Geriatric Nutritional Risk Index: a new index for evaluating at-risk elderly medical patients
Am J Clin Nutr
Overview of the SF-36 Health Survey and the International Quality of Life Assessment (IQOLA) Project
J Clin Epidemiol
Use of the subjective global assessment to predict health-related quality of life in chronic kidney disease stage 5 patients on maintenance hemodialysis
J Ren Nutr
What is the impact of nutritional status on health-related quality of life in hemodialysis patients?
J Ren Nutr
Nutritional status affects quality of life in Hemodialysis (HEMO) Study patients at baseline
J Ren Nutr
Association of nutritional markers with physical and mental health status in prevalent hemodialysis patients from the HEMO study
J Ren Nutr
Quality of life implications of inadequate protein nutrition among hemodialysis patients
J Ren Nutr
Nutritional status and its relationship to quality of life in a sample of chronic hemodialysis patients
J Ren Nutr
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Financial Disclosure: The authors declare that they have no relevant financial interests.
Support: See Acknowledgments on page 116.