Assessment and management of nutrition in hemodialysis patients

Anil Kumar Bhalla; Vinant Bhargava; Priti Meena

doi:10.4103/jrnm.jrnm_3_20

SHORT REVIEW

Year : 2019 | Volume : 5 | Issue : 4 | Page : 83-87

Assessment and management of nutrition in hemodialysis patients

Anil Kumar Bhalla, Vinant Bhargava, Priti Meena
Department of Nephrology, Institute of Renal Science, Sir Gangaram Hospital, New Delhi, India

Date of Submission	20-Feb-2020
Date of Acceptance	01-Mar-2020
Date of Web Publication	09-Jun-2020

Correspondence Address:
Dr. Anil Kumar Bhalla
Institute of Renal Science, Sir Gangaram Hospital, New Delhi
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jrnm.jrnm_3_20

Abstract

Malnutrition is prevalent in patients on hemodialysis. About 18%–75% of patients with chronic kidney disease, undergoing maintenance dialysis, show evidence of wasting. The genesis of malnutrition in hemodialysis patients is multifactorial and comprises reduced dietary nutrient intake, metabolic derangements associated with uremia, and the adverse effects of hemodialysis and other concurrent morbid conditions. In spite of much progress done in recent years in recognizing the pathomechanistic link between malnutrition and mortality, consensus regarding the therapeutic strategies to deal with nutrition-related clinical problems is lacking. Protein–energy wasting (PEW) is the most influential risk factor for adverse outcomes and death. Nutritional supplementation (orally or parenterally) is useful in the management of PEW.

Keywords: Hemodialysis, intradialytic parenteral nutrition, malnutrition, protein–energy wasting

How to cite this article:
Bhalla AK, Bhargava V, Meena P. Assessment and management of nutrition in hemodialysis patients. J Renal Nutr Metab 2019;5:83-7

How to cite this URL:
Bhalla AK, Bhargava V, Meena P. Assessment and management of nutrition in hemodialysis patients. J Renal Nutr Metab [serial online] 2019 [cited 2020 Jul 14];5:83-7. Available from: http://www.jrnm.in/text.asp?2019/5/4/83/286278

Introduction

Nutrition is one of the most important perspectives to consider in patients with end-stage renal disease undergoing maintenance hemodialysis. Nutrition health in hemodialysis patients plays an essential role in decreasing complications and enhancing the quality of life of patients, so providing adequate nutrition should be an integral part of the process of the treatment program in these patients. In 2009, the International Society of Renal Nutrition and Metabolism (ISRNM) recommended the term protein–energy wasting (PEW) syndrome to describe the loss of body protein mass and fuel reserves in dialysis patients, and they had also developed objective criteria for the diagnosis of PEW syndrome in dialysis^[1] Various terms have been used to describe the syndrome of malnutrition in chronic kidney disease (CKD) such as uremic malnutrition, uremic (renal) cachexia, protein–energy malnutrition, malnutrition–inflammation–atherosclerosis syndrome, or malnutrition–inflammation complex (or cachexia) syndrome. This review article aims to describe the prevalence, causes [Figure 1], and methods of assessment of malnutrition in hemodialysis patients. It also attempts to give an insight into treatment strategies in these patients.

Figure 1: Pathogenesis of protein–energy wasting in dialysis patients

Click here to view

Prevalence and Causes of Malnutrition in Hemodialysis Patients

Surveys using various measures and scales of nutritional status indicate that approximately 18%–75% of patients undergoing maintenance dialysis therapy have underlying malnutrition.^[2]

PEW is often associated with diminished functional capacity related to metabolic stress. Inadequate diet intake either due to anorexia or dietary restrictions prescribed in these patients is the major factor responsible for protein or energy depletion. In hemodialysis patients, increased production of inflammatory cytokines associated with high catabolic state results in oxidative and carbonyl stress in the body, acidemia, endocrine disorders such as resistance to insulin, growth hormone, and insulin-like growth factor-1, hyperglucagonemia, hyperparathyroidism contributing to malnutrition. Factors in dialysis patients such as nutrient losses into the dialysate and loss of blood into the hemodialyzer are the essential factors attributable to malnutrition. Furthermore, comorbid conditions such as diabetes mellitus, cardiovascular disease, infection, and aging also contribute to PEW.^[3]

PEW predisposes to infections, increased hospitalizations, poor quality of life, and decreased survival. It also contributes to atherosclerotic cardiovascular disease and vascular calcification.^[4]

Assessment of Nutrition

Assessment of nutritional status requires composite quantitative and qualitative estimation of visceral and somatic (muscle) energy balance and protein stores. A single parameter is unlikely to determine the phenotype of this comorbid state adequately. Therefore, for a comprehensive assessment of nutritional status, several different measurements are required.

The nutritional status assessment should include a combination of clinical, biophysical, and biochemical parameters. Dietary assessment may be done by the 3-day dietary intake recall, assessing adequate intake per day, and further questioning about anorexia, weight loss, and gastrointestinal symptoms such as nausea, diarrhea, and vomiting. Problems such as difficulty in chewing or swallowing as well as poor dentition must also be considered.^[5]

Clinical assessment of dynamic parameters such as weight and body mass index (BMI) is an essential component of a routine examination. Measurement of the circumference of a limb (e.g., mid-arm and calf) and skinfold thickness provides information on the energy stores (fat) of the body.^[6] Various sites for skinfold measurement are as follows:

Biceps skinfold
Triceps skinfold
Subscapular skinfold
Suprailiac skinfold.

The most frequently used laboratory parameters of nutritional status are serum concentrations of hemoglobin, albumin, prealbumin, and transferrin.^[7] Although hypoalbuminemia has been considered as a strong predictor of mortality and morbidity in hemodialysis patients, serum prealbumin seems to have a closer association with nutritional status as it has a shorter half-life than albumin.^[8] Low level of serum creatinine concentration is also an indicator of skeletal muscle wasting as it suggests reduced dietary protein intake and low skeletal muscle mass. In the clinically stable patient on hemodialysis, protein nitrogen appearance (PNA) can be used to estimate the intake of protein. PNA is normalized PNA to body weight (e.g., actual, adjusted, or standardized [NHANES II] body weight or body weight derived from the urea distribution space [Vurea/0.58]) and is determined by urea kinetic modeling. A value of PNA <1.2 g/kg/d in a hemodialysis patient is suggestive of poor nutrition status.^[9] Low total cholesterol levels, retinol-binding protein, and ferritin are additional biochemical markers of nutritional status.^[10]

Assessment of Lean Body Mass

In literature, various methods have been applied for objective measurement of muscle mass or lean body mass such as anthropometrics, bioimpedance, and dual-energy X-ray absorptiometry (DEXA).^[11] Single- and multi-frequency bioelectrical impedance analysis has recently been used in many studies of the nutritional status of dialysis patients. This method relies on the measure of impedance by the human body to an alternating electrical current. Recently developed bioelectrical impedance vector analysis has become one of the favored methods as it gives information regarding body cell mass and hydration status and can distinguish between muscle mass and fat through measuring the vector length and position.^{[11],[12],[13]} DEXA is an indirect method for the estimation of fat mass, fat-free mass, and bone mineral mass.^[13] It depends on the radiological density analysis of the hip and the spine. The use of other methods such as magnetic resonance tomography and computed tomography for measuring body mass composition is limited due to their restricted availability, expensiveness, and radiation exposure.

Tools Used for the Assessment of the Nutritional Status

There are multiple tools developed for the assessment of nutritional status. Currently, subjective global assessment (SGA) of nutritional status has been used increasingly. It provides a comprehensive overview of the patient with respect to nutrition. It takes into consideration food intake, functional capacity, potential malabsorption, reasons for reduced food intake, weight loss, and changes in body composition. Classification using SGA is a dynamic process and this classification can change, even in a relatively short period of time. SGA correlates well with other nutritional markers and has a high predictive value for mortality in these patient groups.^[14] SGA-Dialysis Malnutrition Score was developed as a modification of the original SGA score incorporating duration of hemodialysis into the assessment, converting the semi-quantitative SGA to a fully quantitative score.^[15] Another score, malnutrition–inflammation score (MIS), developed by Kalantar-Zadeh is a combination of anthropometric data, biochemical data, and SGA. It has significant correlations with prospective hospitalization and mortality, as well as with measures of anemia, inflammation, and nutrition in dialysis patients.^[16]

Diagnosis of Protein–energy Wasting

Definition and diagnostic criteria of PEW were proposed by the ISRNM.^[17] It used four categories for the diagnosis of PEW. First, the biochemical criteria: ISRNM prescribes three parameters such as serum albumin (<3.8 g/100 ml, bromocresol green), serum transthyretin (30 mg/100 ml), or serum cholesterol (<2.59 mmol/l). Second, indicators of body mass are used. BMI < 23 kg/m², a loss of 5% of weight within 3 months, and an unintentional loss of 10% of nonedematous weight over the past 6 months are considered as indicators of PEW. Third, muscle wasting, that is, reduced muscle mass 5% over 3 months or 10% over 6 months and reduced mid-arm muscle circumference area (reduction >10% in relation to the 50^th percentile of reference population). And finally, low protein or energy intakes, which are defined as an unintentional reduction in dietary protein intake less than about 0.80 g/kg body weight/day in maintenance dialysis patients or dietary energy intake less than about 25 kcal/kg body weight, respectively, are associated with PEW. For each component, if a patient has a value greater than the threshold value, they receive one point for that component. If a patient has a value less than the threshold value, they receive zero points for that component. Therefore, the total PEW score ranges from 0 to 4. There are four overall PEW score ratings, and they are normal nutritional status (score 4), slight wasting (score 3), moderate wasting (score 2), and severe wasting (score 0–1). Studies that compare the PEW diagnostic criteria with SGA score, MIS, and various anthropometric and biochemical parameters with regard to diagnostic accuracy are lacking in literature.

Nutritional Intervention

Approach to nutrition management in hemodialysis patients should be reformative in nature and should be appropriate according to the changing metabolic and dietary needs of an individual patient. Dietary counseling remains the mainstay of treatment for malnutrition. Educating and advising patients to increase total energy and protein is an essential part of nutritional advice.

Various oral nutritional supplements have been designed in different formulations (solid food, powders, or liquid) to supplement as energy and protein sources.^[18] It is also important to deal with factors such as difficulties in self-feeding, any gastrointestinal problem, depression, infections, diabetes control, and management of comorbidities that could affect food intake. Recommendations for dietary nutrient intake for hemodialysis patients are given in [Table 1].^[19]

Table 1: Recommended nutritional parameters in hemodialysis patients

Click here to view

Treatment of metabolic acidosis results in the improvement of nutritional status by decreasing the rate of protein catabolism. Oral low-dose sodium bicarbonate (2–3 g/d) is recommended to prevent metabolic acidosis.^[20]

Adequate Dialysis

Providing adequate dialysis is essential for maintaining optimal nutritional status. Amelioration of nutritional status during the initial 1^st year of dialysis therapy initiation has been shown to cause an increase in body fat mass. Epidemiological studies have shown a direct correlation between increased mortality and inadequate dialysis doses.^[21] Nutritional status has not been shown to improve by either increasing the dose of dialysis or with the use of high-flux dialysis.^[22] Hemodiafiltration has also been claimed to improve nutritional status by decreasing inflammatory mediators, but it failed to demonstrate proven efficacy in improving nutritional status.

Treatment of Micronutrient Deficiencies

Micronutrient deficiencies should be promptly recognized and treated. Water-soluble micronutrients, such as Vitamin C and Vitamin B, may be lost during hemodialysis sessions, but benefits of routine supplementation of these micronutrients are not clearly known.^[23] Deficiency of L-carnitine has also been related to anemia, intradialytic hypotension, and muscle weakness. The role of L-carnitine supplementation is still controversial.^[24]

Appetite Stimulants

Megestrol acetate is an oral synthetic derivate of the naturally occurring hormone progesterone. It stimulates appetite by releasing neuropeptide Y in the hypothalamus modulation of calcium channels in the satiety center (ventromedial hypothalamus). Side effects that have been reported so far are headaches, uterine bleeding, weight gain, diarrhea, and hyperglycemia after long-term administration of megestrol.^[25] However, because of the lack of adequate evidence, it is not recommended in clinical practice to treat anorexia in malnourished hemodialysis patients. Randomized controlled trials are warranted.

Androgenic Anabolic Steroids

Although androgenic–anabolic steroids (AAS) had shown positive results in patients with burns, cancer, and human immunodeficiency virus infection, data to extrapolate these results in hemodialysis patients are lacking. Nandrolone decanoate and oxandrolone are the two commonly used AASs in clinical practice. They induce messenger RNA expression of skeletal muscle androgen receptor, stimulate net muscle protein synthesis, and inhibit protein catabolic processes. Side effects associated with AAS come from reports among athletes, with complaints of such as hypercoagulation, testicular atrophy and infertility in men, irregular menses, virilization, and hirsutism in women, psychiatric disorders and hepatocellular carcinoma.^[26]

Role of Intradialytic Parenteral Nutrition

Intradialytic parenteral nutrition (IDPN) serves as an alternate option for the patients who cannot tolerate oral or enteral route nutritional feeding. These are usually patients suffering from GI tract dysfunction, severe nausea, vomiting, or anorexia. This form of nutrition is administered during regular dialysis sessions. Side effects such as increased risk of infections, fluid overload, metabolic imbalance, and increased financial burden raise concerns for its use when compared to other therapies. Current evidence is still scarce to show any benefit for IDPN over recommended standard treatments.^[27] According to the Kidney Disease Outcomes Quality Initiative, 2000, indications for initiating IDPN are the following:^[28]

Evidence of protein or energy malnutrition and inadequate dietary protein intake or dietary energy intake
Inability to administer or tolerate adequate oral nutrition, including food supplements or tube feeding.

Conclusion

PEW is an important cause of morbidity in CKD patients (predialysis/on dialysis). It should be looked for using various measurements, assessments, and diagnostic tools. Treating PEW results in significant improvement in the quality of life and prolongs survival.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	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. Kidney Int 2008;73:391-8.
2.	Locatelli F, Fouque D, Heimburger O, Drüeke TB, Cannata-Andía JB, Hörl WH, et al. Nutritional status in dialysis patients: A European consensus. Nephrol Dial Transplant 2002;17:563-72.
3.	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.
4.	Dwyer JT, Larive B, Leung J, Rocco MV, Greene T, Burrowes J, et al. Are nutritional status indicators associated with mortality in the hemodialysis (HEMO) study? Kidney Int 2005;68:1766-76.
5.	Ikizler TA, Greene JH, Wingard RL, Parker RA, Hakim RM. Spontaneous dietary protein intake during progression of chronic renal failure. J Am Soc Nephrol 1995;6:1386-91.
6.	Schoenfeld PY, Henry RR, Laird NM, Roxe DM. Assessment of nutritional status of the national cooperative dialysis study population. Kidney Int Suppl 1983:S80-8.
7.	Iseki K, Kawazoe N, Fukiyama K. Serum albumin is a strong predictor of death in chronic dialysis patients. Kidney Int 1993;44:115-9.
8.	Chertow GM, Ackert K, Lew NL, Lazarus JM, Lowrie EG. Prealbumin is as important as albumin in the nutritional assessment of hemodialysis patients. Kidney Int 2000;58:2512-7.
9.	Panzetta G, Tessitore N, Faccini G, Maschio G. The protein catabolic rate as a measure of protein intake in dialysis patients: usefulness and limits. Nephrol Dial Transplant 1990;5 Suppl 1:125-7.
10.	Qureshi AR, Alvestrand A, Danielsson A, Divino-Filho JC, Gutierrez A, Lindholm B, et al. Factors predicting malnutrition in hemodialysis patients: A cross-sectional study. Kidney Int 1998;53:773-82.
11.	Abrahamsen B, Hansen TB, Høgsberg IM, Pedersen FB, Beck-Nielsen H. Impact of hemodialysis on dual X-ray absorptiometry, bioelectrical impedance measurements, and anthropometry. Am J Clin Nutr 1996;63:80-6.
12.	Formica C, Atkinson MG, Nyulasi I, McKay J, Heale W, Seeman E. Body composition following hemodialysis: Studies using dual-energy X-ray absorptiometry and bioelectrical impedance analysis. Osteoporos Int 1993;3:192-7.
13.	Svendsen OL, Haarbo J, Heitmann BL, Gotfredsen A, Christiansen C. Measurement of body fat in elderly subjects by dual-energy X-ray absorptiometry, bioelectrical impedance, and anthropometry. Am J Clin Nutr 1991;53:1117-23.
14.	Detsky AS, McLaughlin JR, Baker JP, Johnston N, Whittaker S, Mendelson RA, et al. What is subjective global assessment of nutritional status? JPEN J Parenter Enteral Nutr 1987;11:8-13.
15.	Detsky AS, Baker JP, Mendelson RA, Wolman SL, Wesson DE, Jeejeebhoy KN. Evaluating the accuracy of nutritional assessment techniques applied to hospitalized patients: Methodology and comparisons. JPEN J Parenter Enteral Nutr 1984;8:153-9.
16.	Lopes AA. The malnutrition-inflammation score: A valid nutritional tool to assess mortality risk in kidney transplant patients. Am J Kidney Dis 2011;58:7-9.
17.	Riella MC. Nutritional evaluation of patients receiving dialysis for the management of protein-energy wasting: What is old and what is new? J Ren Nutr 2013;23:195-8.
18.	Stratton RJ, Bircher G, Fouque D, Stenvinkel P, de Mutsert R, Engfer M, et al. Multinutrient oral supplements and tube feeding in maintenance dialysis: A systematic review and meta-analysis. Am J Kidney Dis 2005;46:387-405.
19.	NKF-DOQI clinical practice guidelines for nutrition in chronic renal failure. Am J Kidney Dis 2000;35 Suppl 2:S1-40.
20.	Williams AJ, Dittmer ID, McArley A, Clarke J. High bicarbonate dialysate in hemodialysis patients: Effects on acidosis and nutritional status. Nephrol Dial Transplant 1997;12:2633-7.
21.	Ikizler TA. Effects of hemodialysis on protein metabolism. J Ren Nutr 2005;15:39-43.
22.	Eknoyan G, Beck GJ, Cheung AK, Daugirdas JT, Greene T, Kusek JW, et al. Effect of dialysis dose and membrane flux in maintenance hemodialysis. N Engl J Med 2002;347:2010-9.
23.	Laville M, Fouque D. Nutrition and hemodialysis. Kidney Int 2000;58 Suppl 76:S133-9.
24.	Hurot JM, Cucherat M, Haugh M, Fouque D. Effects of L-carnitine supplementation in maintenance hemodialysis patients: A systematic review. J Am Soc Nephrol 2002;13:708-14.
25.	Boccanfuso JA, Hutton M, McAllister B. The effects of megestrol acetate on nutritional parameters in a dialysis population. J Ren Nutr 2000;10:36-43.
26.	Orr R, Fiatarone Singh M. The anabolic androgenic steroid oxandrolone in the treatment of wasting and catabolic disorders: Review of efficacy and safety. Drugs 2004;64:725-50.
27.	Bilbrey G. Is intradialytic parenteral nutrition of benefit in hemodialysis patients? Semin Dial 1993;6:168-70.
28.	The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF KDOQI). KDOQI Clinical Practice Guidelines for Nutrition in Chronic Renal Failure Guideline 19: Indications for Nutritional Support; 2000.