• Users Online: 326
  • Print this page
  • Email this page

Table of Contents
Year : 2019  |  Volume : 5  |  Issue : 3  |  Page : 59-63

Assessing protein-energy wasting in chronic kidney disease

1 Chairman, Department of Nephrology, Sir Ganga Ram Hospital, New Delhi, India
2 Professor, Department of Nephrology, Sanjay Gandhi Postgraduate Institute of Medical, Lucknow, Uttar Pradesh, India

Date of Submission10-Jan-2020
Date of Acceptance10-Jan-2020
Date of Web Publication17-Feb-2020

Correspondence Address:
Dr. Anita Saxena
Department of Nephrology, Sanjay Gandhi Postgraduate Institute of Medical, Lucknow, Uttar Pradesh
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jrnm.jrnm_1_20

Rights and Permissions

Patients with chronic kidney disease, both predialysis and those on dialysis, are vulnerable to the onslaught if disease which presents in the form of malnutrition and muscle wasting. These two conditions are associated with increased morbidity and mortality which mandates thorough assessment and intervention with the progression of the disease, keeping in mind comorbidities, infection, and intercurrent illness. As no single tool alone can assess the nutritional status of these patients, a systematic approach for the assessment of nutritional status and monitoring dietary prescription with timely follow-up is a prerequisite for mending the quality of life of these patients.

Keywords: Chronic kidney disease, nutrition assessment, nutrition screening, protein-energy wasting

How to cite this article:
Bhalla AK, Saxena A. Assessing protein-energy wasting in chronic kidney disease. J Renal Nutr Metab 2019;5:59-63

How to cite this URL:
Bhalla AK, Saxena A. Assessing protein-energy wasting in chronic kidney disease. J Renal Nutr Metab [serial online] 2019 [cited 2022 Aug 20];5:59-63. Available from: http://www.jrnm.in/text.asp?2019/5/3/59/278610

“The mediocre teacher tells. The good teacher explains. The superior teacher demonstrates. The great teacher inspires.

–William Arthur Ward

Malnutrition is a common finding in patients with chronic kidney disease (CKD) and end-stage renal disease. The prevalence of malnutrition varies from 50% to 75% in various studies.[1],[2] In recent years, the importance of nutritional assessment in patients with CKD has been emphasized implying that malnutrition is associated with an increased risk of morbidity and mortality. The question here is “what is the simplest and less time engaging process of assessing nutritional status?”

According to the NKF-KOQI clinical practice guidelines for nutrition in CKD published in 2000, “nutritional status in maintenance dialysis (MD) patients should be assessed with a combination of valid complementary measures rather than by any single measure alone because no single measure provides a comprehensive indication of nutritional status. The measures of intake, visceral and somatic protein stores, body composition, and functional status identify the different aspects of nutrition status.[3]” Patients with declining renal failure and those undergoing MD have a poor appetite which affects protein and energy intake. This demands the periodic assessment of nutritional status for taking appropriate measures for improved outcomes.[4],[5],[6],[7],[8],[9],[10],[11],[12] Hence, a panel of measures recommended for assessing nutrition status include (i) laboratory values, (ii) body composition, (iii) dietary intake, and (iv) scoring. The International Society of Renal Nutrition and Metabolism has proposed criteria for diagnosing protein-energy wasting (PEW).[13],[14]

Evaluation begins with screening the patient for identifying patients at risk of malnutrition so that more extensive nutrition assessment can be performed. Nutrition screening is a simple and rapid process and addresses three or four basic questions such as recent weight loss, current body mass index (BMI), disease severity, and recent food intake. Screening is focused and sensitive enough to detect all or nearly all the patients at nutritional risk. Out of several screening tools available (Geriatric Nutrition Risk Index, Mini Nutritional Assessment (MNA), Malnutrition Universal Screening Tool (MUST), and Nutritional Risk Screening-2002 (NRS-2002),[15],[16],[17],[18] the components of the malnutrition screening tool (MST) have acceptable sensitivity and specificity, suggesting that it can play a valuable role in quickly identifying the risk of malnutrition in the residential aged care setting.[15],[16],[17],[18] The MST tool is easy to perform and focusses on two questions: (1) have you lost weight recently without trying and (2) have you been eating poorly because of a decreased appetite?

A study on 752 patients using NRS-2002, MUST, MST, and SNAQ showed the nutrition risk to be 29.3%, 37.1%, 33.6%, and 31.3%, respectively, from each of the respective tools.[15]

The study infers that patients at nutrition risk showed a higher risk of the very long length of hospital stay as compared with those not at nutrition risk, independent of the tool applied (relative risk, 1.35–1.78). Increased risk of mortality (2.34 times) was detected by the MUST.[15],[16],[17],[18]

The European Society of Clinical Nutrition and Metabolism recommended that the NRS-2002[16] combines both a measure of current potential under nutrition and a measure of disease severity and has been validated in various patient groups. The NRS has equivalent sensitivity and specificity compared to the subjective global assessment (SGA), but it is quicker and simpler and thus requires considerably less training.[15],[16],[17],[18] Functional, psychological, and cognitive parameters, not considered in MUST and NRS-2002 tools, are probably more important risk factors for malnutrition than acute illness in geriatric long-term care inpatient settings. These confounding factors can account for the low predictive value of these tests. MNA-SF seems to combine the predictive capacity of the full version of the MNA with a sufficiently short time of administration.

The formatted interview session with the patient provides an important clue to patients who might be malnourished. The symptoms such as nausea, vomiting, fatigue, anorexia, and weight loss/gain throw light on nutritional deficit caused by reduced intake and/or fluid retention (edema). The interviews along with the clinician's prescription provide information on pharmacological therapy that may induce increased hunger (steroids) or cause reduced appetite (such as iron therapy and phosphorus binders). Interviews also give an opportunity to assess comorbidities and any psychological issues due to disease, family support, and financial pressure.

In CKD, poor adherence to diet, medications, and treatment varies between 20% and 70% depending on the assessment method (objective versus self-reported). Higher mortality and morbidity have been reported in patients, who do not meet “goals” defined by the health-care team.[19] Dietary intake studies have shown difficulty in adhering to the scope and complexity of the CKD diet parameters. So far, no single educational or clinical strategy has been shown to be consistently effective across CKD populations.

Highest adherence has been observed when both diet and education efforts are individualized to each patient and adapted over time to changing lifestyle and CKD variables.[19],[20],[21]

The assessment of dietary history plays a pivotal role in deciding nutritional intervention. In a stable patient, this information can be obtained from the patient himself; however, if a patient is ill, the information should be obtained from the caretakers like wife or children. There are several tools for the assessment of dietary intake such as food frequency questionnaire (FFQ), 24 h dietary recall, obtaining a food record of 3 days. Three days recall would include food intake of 2 week days and 1 week end day.. According to ISRNM consensus statement on the definition of PEW, unintentional low dietary energy intake of <25 kcal/kg/day for least 2 months and low dietary protein intake (DPI) of <0.8 g/kg/day for at least 2 months for maintenance hemodialysis patients or <0.60 g/kg/day for patients with CKD stage 2–5 with 5 g/day of urinary protein loss among others are pointers for PEW.[13],[14]

Patients who require intensive nutritional counseling can be advised to follow open-ended dietary assessment methods such as weighed food records (WFRs)[21] for multiple days (nonconsecutive days or consecutive days) in which the patient weighs the portion of uncooked and cooked food. WFRs measure the actual intake of the patient (weight and the food portions) and are considered superior to food frequency questionnaires. This measure also takes into consideration the portion of food not consumed by the patient.

This method is cumbersome as the dietician or health worker has to make home visits at the time when food is being prepared. However, in modern times, the patient can take pictures of the portion sizes and share them with the dietician or health worker. Pictures are taken every time the patient eats or every time they take medication over 24 h or between dialysis sessions. Each picture has a time and date automatically recorded by the device, which makes recall easy. Intakes can be enhanced because foods can be seen and discussed which will make nutrition sessions more realistic. This lifestyle recording makes nutrition sessions more realistic.[22],[23],[24],[25] Semiquantitative food frequency questionnaire during the specific reference time period can also be used.

Physical examination of patients begins right from the moment the patient steps into the clinic. The most revealing parts of the body include the face (tiredness, puffiness, prominent cheekbones due to wasting, and wasting of temporalis muscle), clavicles (loss of subcutaneous fat and muscles), the wrist, and forearms (muscle wasting/sagging skin and color of the skin). After the visual assessment, anthropometric measurements should be done (actual body weight and mid-upper arm circumference [MUAC]).

Skinfold measurements should be taken provided the patient is not edematous. Percentile change of dry weight should be assessed approximately every month. A nutritionist must ensure to carry scientific-nonstretchable measuring tape and skinfold calipers to the clinic and the ward.

Nutritional assessment is incomplete without anthropometric evaluation. The most commonly used measurements include height, edema-free ideal body weight, BMI, skin folds (biceps, triceps, subscapular, and suprailiac),[22] which give an estimate of body fat in the absence of edema. MUAC is an excellent measurement for following up the effect of nutritional intervention or when the patient is at risk of developing malnutrition. A more accurate but expensive method of estimating lean body mass and fat stores is dual-energy X-ray absorptiometry (DEXA). Follow-up with DEXA can be done as and when required (but at least once a year to keep abreast of the bone health of the patient). The only flaw with DEXA is that it does not differentiate between different water compartments, and it is not available at all centers. A less expensive and bedside tool for clinical use which has been calibrated for different populations is bioelectrical impedance analysis (BIA).[3],[26],[27],[28] BIA can be used for effective fluid management and for estimating dry weight. In patients on peritoneal dialysis, for accurate results, BIA should be done when the patient is in an edema-free or near-edema-free state and should be performed when the patient is dry (the peritoneal cavity drained of dialysate).

Malnutrition can be identified with greater sensitivity and specificity using a combination of factors. In a clinical setting, the most frequently used laboratory parameters include serum albumin (≥4.0 g/dL for the bromcresol green method), serum prealbumin >30 mg/dL (the two are acute-phase negative reactant proteins), serum cholesterol (<100 mg/dL is alarming; suggestive of chronic protein-energy deficits and/or the presence of comorbid conditions, including inflammation),[3] serum transferrin, but serum albumin and serum prealbumin are highly influenced by trauma, infection, and hydration status. Low or declining serum cholesterol concentrations are predictive of increased mortality risk. From the assessment's point of view, high-sensitivity C-reactive protein (CRP)[3] is a positive acute-phase reactant (APR) protein that correlates negatively with the concentrations of visceral proteins. CRP is not a direct nutritional marker, but in the presence of low levels of serum albumin or pre-albumin (negative APRs), potential causes of protein depletion that are not related to diet should be consider. If CRP levels are high, the sources of infection, inflammation, or both should be investigated and resolved.

The BUN and creatinine, taken together, are valuable screening tests in evaluating renal disease. Serum creatinine can be used as a marker of muscle mass. It can be low in malnourished patients with depleted muscle stores. BUN signifies a balance between urea production (in the liver), urea breakdown, and urea elimination (through the kidneys).[29],[30],[31],[32],[33] Slightly elevated BUN implies diet high in protein [Box 1]. Urea production is increased by a high-protein diet and decreased by low-protein diet, malnutrition or starvation, and by impaired metabolic activity in the liver. On a normal diet, the body produces about 12 g of urea each day, and the kidneys eliminate ~ 10 g/day. High-protein diet[30] BUN can be raised in the hypercatabolic state (fever or infection and inflammatory states, which increases protein breakdown, gut bleeding, and in dehydration or low water consumption (one can use this as a measure of hydration in the patients). BUN can also increase in the period of stress as stress increases the activation of the sympathetic, renin-angiotensin-aldosterone, and vasopressin. This situation can be observed in heart failure.

The normalized protein catabolic rate (nPNA)[3] though cumbersome and hence not used routinely at many centers is used to assess DPI in dialysis patients, as a means toward determining nutritional adequacy. Several factors can affect nPNA such as protein intake, dialysis dose, anabolic, and catabolic factors. [Box 2] shows the ideal situation when nPNA reflects DPI. Nutritional adequacy requires grading. SGA,[36],[37],[38] malnutrition inflammation score (MIS), and dialysis malnutrition score (DMS) are easy to use scoring systems.[39],[40] SGA gives an overall assessment based on the changes in weight, gastrointestinal symptoms, dietary intake right from being hypocaloric, anorectic to normal, and improved intake of food, along with physical independence, i.e., functional impairment. Any deficit in terms of loss of subcutaneous fat, muscle loss, and overhydration as perceived by edema and ascites is captured in the physical examinations.

MIS and DMS are used for the assessment of the nutritional status of patients on MD. The two are an improvization of SGA score as it not only takes into account medical history, changes in body composition, and functional capability but also includes dialysis vintage and biochemical parameters such as serum albumin and serum transferrin.

The serum creatinine and the creatinine index[3] reflect sum of dietary intake of foods rich in creatine and creatinine (muscle/nonvegetarian intake) and endogenous (skeletal muscle) creatinine production, excluding urinary excretion, dialytic removal, and endogenous degradation of creatinine and are, therefore, recommended as valid and clinically useful markers of protein-energy nutritional status in MD patients. In clinical practice, while inferring the levels of creatinine, the muscle mass of the patient must be kept in consideration. Low predialysis or stabilized serum creatinine is indicative of protein-energy malnutrition and wasting of the skeletal muscle. A low creatinine index suggests low DPI, diminished skeletal muscle mass, and increased risk of mortality.

  Conclusion Top

Patients with CKD, both predialysis and those on dialysis, are vulnerable to the onslaught if disease, which presents in the form of malnutrition and muscle wasting.[17],[41] These two conditions are associated with increased morbidity and mortality which mandates thorough assessment and intervention with the progression of the disease, keeping in mind comorbidities, infection, and intercurrent illness. As no single tool alone can assess the nutritional status of these patients, a systematic approach for the assessment of nutritional status and monitoring dietary prescription with timely follow-up is a prerequisite for mending the quality of life of these patients.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Kopple JD. MaCollum award lecture, PEM in maintainence dialysis patients. Am J Clin Nutr 1996;65:1544–57.  Back to cited text no. 1
Sen D, Prakash J. Nutrition in dialysis patients. J Assoc Physicians India 2000;48:724-30.  Back to cited text no. 2
K/DOQI clinical practice guidelines for nutrition in chronic renal failure adult guidelines on maintenance dialysis Guideline 1 Evaluation of protein-Energy Nutritional Status. Am J Kid Dis 2000;35:S17-21.  Back to cited text no. 3
Klahr S, Levey AS, Beck GJ, Caggiula AW, Hunsicker L, Kusek JW, et al. The effects of dietary protein restriction and blood-pressure control on the progression of chronic renal disease. Modification of Diet in Renal Disease Study Group. N Engl J Med 1994;330:877-84.  Back to cited text no. 4
Patel Z, Bhattacharjee LI, Shah BV. The role of dietary protein restriction in Indian patients with chronic renal failure. J Assoc Physicians India 2000;48:1078-81.  Back to cited text no. 5
Beheary SS, Shah BV. Dietary protein intake in Indian patients with chronic renal failure. Ind J Nephrol 1996;6:19-21.  Back to cited text no. 6
Blagg CR. Importance of nutrition in dialysis patients. Am J Kid Dis 1991;17:458-61.  Back to cited text no. 7
Blumenkrantz MJ, Kopple JD, Gutman RA, Chan YK, Barbour GL, Roberts C, et al. Methods for assessing nutritional status of patients with renal failure. Am J Clin Nutr 1980;33:1567-85.  Back to cited text no. 8
Destky AS, Laughiln MJ, Baker JP, Johnston N, Whittaker S, Mendelson RA, et al. What is subjective global assessment of nutritional status? J Parenter Enteral Nutr 1987;11:8-3.  Back to cited text no. 9
Lawson JA, Lazarus R, Kelly JJ. Prevalence and prognostic significance of malnutrition in chronic renal insufficiency. J Ren Nutr 2001;11:16-22.  Back to cited text no. 10
McCann L. Subjective global assessment as it pertains to the nutritional status of dialysis patients. Dial Transplant 1996;25:190-202.  Back to cited text no. 11
Bross R, Noori N, Kovesdy CP, Murali SB, Benner D, Block G, et al. Dietary assessment of individuals with chronic kidney disease. Semin Dial 2010;23:359-64.  Back to cited text no. 12
Fouque D, Kalantar-Zadeh K, Kopple J, Cano N, Chauveau P, Cuppari L, et al. A proposed nomenclature and diagnostic criteria for protein-energy wasting in acute and chronic kidney disease. Kid Int 2008;73:391-8.  Back to cited text no. 13
Carrero JJ, Stenvinkel P, Cuppari L, Ikizler TA, Kalantar-Zadeh K, Kaysen G, et al. Etiology of the protein-energy wasting syndrome in chronic kidney disease: A consensus statement from the International Society of Renal Nutrition and Metabolism (ISRNM). J Ren Nutr 2013;23:77-90.  Back to cited text no. 14
Donini LM, Poggiogalle E, Molfino A, Rosano A, Lenzi A, Rossi Fanelli F, et al. Mini-nutritional assessment, malnutrition universal screening tool, and nutrition risk screening tool for the nutritional evaluation of older nursing home residents. J Am Med Dir Assoc 2016;17:959.e11-8.  Back to cited text no. 15
Rabito EI, Marcadenti A, da Silva Fink J, Figueira L, Silva FM. Nutritional risk screening 2002, short nutritional assessment questionnaire, malnutrition screening tool, and malnutrition universal screening tool are good predictors of nutrition risk in an emergency service. Nutr Clin Pract 2017;32:526-32.  Back to cited text no. 16
Isenring EA, Bauer JD, Banks M, Gaskill D. The malnutrition screening tool is a useful tool for identifying malnutrition risk in residential aged care. J Hum Nutr Diet 2009;22:545-50.  Back to cited text no. 17
Velasco C, García E, Rodríguez V, Frias L, Garriga R, Alvarez J, et al. Comparison of four nutritional screening tools to detect nutritional risk in hospitalized patients: A multicentre study. Eur J Clin Nutr 2011;65:269-74.  Back to cited text no. 18
Acchiardo SR, Moore LW, Latour PA. Malnutrition as the main factor in morbidity and mortality of hemodialysis patients. Kid Int Suppl 1983;16:S199-203.  Back to cited text no. 19
Rizzo NS, Jaceldo-Siegl K, Sabate J, Fraser GE. Nutrient Profiles of Vegetarian and Nonvegetarian Dietary Patterns. J Acad Nutr Diet Dec 2013;113:1610-9.  Back to cited text no. 20
Ishii Y, Ishihara J, Takachi R, Shinozawa Y, Imaeda N, Goto C, et al. Comparison of weighed food record procedures for the reference methods in two validation studies of food frequency questionnaires. J Epidemiol 2017;27:331-7.  Back to cited text no. 21
Saxena A. The Handbook of Nutrition in Kidney Disease: Part of the Oxford Clinical Practice Series. Publishers Oxford University Press; 2017.  Back to cited text no. 22
Heymsfield SB, Tighe A, Wang ZM. Nutritional assessment by anthropometric and biochemical methods. In: Shils ME, Olson JA, Shike M, editors. Modern Nutrition in Health and Disease. Vol. 8. Philadelphia, PA: Lea and Febige; 1993. p. 1094-98.  Back to cited text no. 23
Beto JA, Schury KA, Bansal VK. Strategies to promote adherence to nutritional advice in patients with chronic kidney disease: A narrative review and commentary. Int J Nephrol Renovasc Dis 2016;9:21-33.  Back to cited text no. 24
Bates CJ, Prentice A, Finch S. Gender differences in food and nutrient intakes and status indices from the National Diet and Nutrition Survey of people aged 65 years and over. Eur J Clin Nutr 1999;53:694-9.  Back to cited text no. 25
Saxena A, Sharma RK, Gupta A, John MM. Noninvasive method for preventing intradialytic hypotension. Saudi J Kidney Dis Transplant 2015;26:896-905.  Back to cited text no. 26
Saxena A, Sharma R, Gupta A. Graft Function and nutritional parameters in stable post renal transplant patients Saudi J Kid Dis Transplant Year: 2016;27:356-61.  Back to cited text no. 27
Saxena A, Gupta A, Abraham G, Sakhuja V, Jha V. Bioelectrical impedance analysis can be used as screening tool for chronic kidney disease. Saudi Saudi J Kid Dis Transplant 2015;26:1311-13.  Back to cited text no. 28
Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron 1976;16:31-41.  Back to cited text no. 29
Doolan PD, Alpen EL, Theil GB. A clinical appraisal of the plasma concentration and endogenous clearance of creatinine. Am J Med 1962;32:65-79.  Back to cited text no. 30
Dossetor JB. Creatininemia versus uremia. The relative significance of blood urea nitrogen and serum creatinine concentrations in azotemia. Ann Intern Med 1966;65:1287-99.  Back to cited text no. 31
Kassirer JP. Clinical evaluation of kidney function – Glomerular function. N Engl J Med 1971;285:385-9.  Back to cited text no. 32
Mitch WE, Collier VU, Walser M. Creatinine metabolism in chronic renal failure. Clin Sci (Lond) 1980;58:327-35.  Back to cited text no. 33
Bauer JH, Brooks CS, Burch RN. Renal function studies in man with advanced renal insufficiency. Am J Kidney Dis 1982;2:30-5.  Back to cited text no. 34
Hosten AO. In: Bun and Creatinine Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd ed., Ch. 193.  Back to cited text no. 35
Dilip R, Bamini M, Selvamani A. Subjective global assessment of nutritional status of patients on maintenance Hemodialysis. Indian J Nephrol 2000;10:163-6.  Back to cited text no. 36
Tapiawala S, Vora H, Patel Z, Badve S, Shah B. Subjective global assessment of nutritional status of patients with chronic renal insufficiency and end stage renal disease on dialysis. J Assoc Physicians India 2006;54:923-6.  Back to cited text no. 37
Fina G, Sicuso C, Alati G, Zoccali C. Subjective global assessment of nutrition in dialysis patients. Neprol Dial Transplant 1993;8:1094-8.  Back to cited text no. 38
Kalantar-Zadeh K, Kopple JD, Block G, Humphreys MH. A malnutrition-inflammation score is correlated with morbidity and mortality in maintenance hemodialysis patients. Am J Kid Dis 2001;38:1251-63.  Back to cited text no. 39
Beberashvili L, Azar A, Sinuani I, Yasur H, Feldman L, Averbukh Z, Weissgarten J. Objective Score of Nutrition on Dialysis (OSND) as an alternative for the malnutrition-inflammation score in assessment of nutritional risk of haemodialysis patients. Nephr Dial Transplant 2010;25:262-671.  Back to cited text no. 40
Chumlea WC, Go SS, Vellas B. Assessment of protein calorie nutrition. In: Kopple JD, Massry SG, editors. Nutritional Management of Renal Disease. Baltimore, MD: Williams and Wilkins; 1998. p. 203-28.  Back to cited text no. 41


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article

 Article Access Statistics
    PDF Downloaded236    
    Comments [Add]    

Recommend this journal