Protein energy wasting (PEW) is a major challenge in CKD. Objective: To assess PEW in predialysis patients on their first visit to a nephrologist. Methods: Three day dietary intake of 484 CKD stage 3 patients was taken. Appetite was assessed with ADAT. Patients were divided into groups based on appetite and BMI. Results: Male and female parameters are serum albumin 3.7 ± 0.84/3.68.8 ± 0.81 g/dL, total protein 7.02 ± 1.27/6.94 ± 1.26 g/dL, creatinine 4.68 ± 4.19/3.74 ± 3.36 mg% creatinine clearance 33.22 ± 30.48/37.55 ± 33.87 ml/minute, BMI 22.60 ± 4.29/23.43 ± 4.77kg/m2 energy/kg 16.97 ± 0.65/16.8 ± 0.64, protein g/kg 0.65 ± 0.28/0.64 ± 0.30, carbohydrate g/kg 2.98 ± 1.54/2.98 ± 0.1.36, fat g/kg 2.98 ± 0.23/2.79 ± 0.22, respectively. As appetite decreased, dietary protein and energy intake decreased significantly. Appetite in males and females: Average 14.46%, 4.13%, poor 9.7%, 18.18%, anorexic 13.2%, 7.4%. Income had strong correlation with BMI (p 0.000), dietary protein (p 0.000), energy (p 0.000) and carbohydrate (p 0.000). Appetite correlated with creatinine (p 0.019), dietary energy, protein, carbohydrate and fat (p 0.000) intake. BMI correlated (p 0.000) with fat, carbohydrate, energy and creatinine clearance. ANOVA showed significant difference within and between appetite groups in energy, protein, fat, carbohydrate, creatinine clearance (p 0.000) and serum albumin (p 0.025). There was significant difference in protein (p 0.026), energy intake (p 0.000) and creatinine clearance (p 0.038) within and between BMI groups. Based on income, there was significant difference among groups in BMI (p 0.000), energy (p 0.019), protein (p 0.031) and albumin (0.001).
In chronic kidney disease (CKD) progressive decline of glomerular filtration rate (GFR) is associated with significant reduction in food intake. Approximately one third of chronic dialysis patients suffer from fair or poor appetite which is related directly to poor patient outcome [
Appetite regulation in renal disease is a complex network of synergistic and antagonistic interactions among hormones, peptides, and cytokines which modulate neuro-chemical systems involved in feeding and energy balance. This is confounded and influenced by other factors such as the dialysis treatment, length of treatment, the modality of dialysis, age, psycho-social Issues, and co-morbid conditions. Appetite regulation involves play of several hormones like ghrelin and neuropeptide YY as an appetite stimulant, and cholecystokinin, glucagon- like peptide-1 as appetite inhibitors, leptin, a potent appetite inhibitor; the vagal system; and the brain, which integrates the stimuli in the hypothalamus area. In nondialyzed chronic renal failure patients and in maintenance dialysis patients, anorexia is related to accumulation of anorexigenic compounds, inflammatory cytokines, and alterations in appetite regulation, such as amino acid imbalance, which increases the transport of free tryptophan across the blood-brain barrier thus creating a hyperserotoninergic state which is associated with low appetite.
Treatment of anorexia involves counseling, starting dialysis treatments in uremic chronic kidney disease patients, increasing the dialysis dose, and possibly using appetite stimulants. However, it is not clear whether and to what extent a reduced appetite is related to the elements of MICS, especially inflammation, in these persons. Anorexia may indeed be a key component in the development and maintenance of PEM, inflammation, and MICS in these patients. An abnormally low appetite per se may be a risk factor in dialysis patients for such unfavorable outcomes as erythropoietin hyporesponsiveness, poor QoL, and increased mortality and hospitalization [
This was a prospective, cross sectional and observational study conducted in the out-patient department. A total of 480 (348 male and 140 female) patients in CKD 3 stage patients were included in the study. Inclusion criteria were first visit of a CKD patient to a nephrologist referred by non-nephrologist physician. Data were collected between year 2013 and 2014. Inclusion criteria for selection of patients were: 1) chronic kidney disease (CKD) patients referred by non-nephrologist physician to a nephrologist; 2) patient was visiting a nephrologist for the first time; and 3) it was not a follow-up visit. Since patients were referred by a non nephrologist physician therefore on their first visit, the biochemical tests which were available from medical record were serum creatinine, albumin, total protein, calcium, and urinary protein.
Evaluation of dietary intake: Three days dietary intake was taken. Dietary intake was taken with the help of standard measuring cups and bowls in an interview. The patients were shown bowls (of different capacities) and cups and were asked to identify the bowl and cup which represented their food intake. Patients were shown portion sizes in order to get as close to their actual dietary intake. Dietary intake was assessed from 3-day diet, interview assisted, recalls administered concurrently with the ADAT. Three days dietary intake was taken by a dietician in a structured dietary interview and the response was noted on proformas. Dietary energy, protein, fat, carbohydrate, calcium and phosphorus intake was analyzed using standard standard National Institute of Nutrition (NIN) Hyderabad table for nutrient values of foods (NIN 1991).
Subjective assessment of appetite: The Appetite and Diet Assessment Tool (ADAT) [
Anthropometric measurements included height in centimeters and body weight in kilograms. Patients were divided into four groups based on body mass index (BMI) [
Results: the biochemical profile of the patients was male and female is given in
Dietary calcium intake was low. However low serum calcium level was within normal range (normal range 8.5 - 10.2 mg/dL)) in males but not in females. Although dietary phosphorus intake was within recommended intake (800 - 1000 mg/d KDOQI), the serum phosphorus was above normal range: 2.7 - 4.6 mg/dL.
Appetite and dietary intake: 162 (male126 female 36) patients had normal appetite and 325 (male 222, female103) had average to poor appetite (
Weight KG | Height CM | BMI kg/m2 | Creatinine mg% | Creat Clear | S Albumin | S Total Protein | S Na | S K | S Ca | S P | BP Syst/Dias | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
M | 61.63 ± 14.08 | 164.74 ± 8.90 | 22.54 ± 4.30 | 4.67±4.19 | 33.4 ± 30.5 | 3.77 ± 0.83 | 7.03 ± 1.27 | 135.4 ± 12.7 | 5.36 ± 10.9 | 8.86 ± 9.87 | 4.86 ± 1.55 | 136.80 ± 24.66/ 84.94 ± 14.44 |
F | 54.99 ± 11.86 | 153.11 ± 6.49 | 23.43 ± 4.77 | 3.74 ± 3.36 | 37.5 ± 33.8 | 3.68 ± 0.81 | 6.94 ± 1.26 | 135.4 ± 5.7 | 4.70 ± 0.7 | 7.5 ± 2.1 | 5.03 ± 1.41 | 139.40 ± 26.6 84.04 ± 13.90 |
M: Male; F: Female; D: Dietary; Cho: Carbohydrate; K: Potassium; Na: Sodium; Ca: Calcium; P: Phosphorus; Creatclear: Creatinine clearance; S: serum.
Sex | Energy Kcal/kg | Energy Deficit | Protein G/kg | Protein Deficit | CHO g/kg | Fat g/kg | D Na mg | D K mg | D Ca mg | D P mg |
---|---|---|---|---|---|---|---|---|---|---|
M | 17.22 ± 8.29 | 17.78 ± 8.29 | 0.66 ± 0.28 | 0.09 ± 28 | 3.12 ± 2.10 | 0.23 ± 0.24 | 222.77 ± 158.94 | 1221.3 ± 562.8 | 453.4 ± 315.49 | 909.66 ± 414.4 |
F | 16.88 ± 7.66 | 18.12 ± 7.66 | 0.64 ± 0.30 | 0.11 ± 0.30 | 2.79 ± 1.36 | 0.22 0.28 | 216.3 ± 164.7 | 1090.4 ± 521.6 | 391.0 ± 291.3 | 783.4 ± 378.8 |
M: Male; F: Female; D: Dietary; Cho: Carbohydrate; K: Potassium; Na: Sodium; Ca: Calcium; P: Phosphorus; Creat clear: Creatinine clearance; S: serum.
BMI | Normal | Underweight | Severely Underweight |
---|---|---|---|
N% | 52.8% | 15% | 5.71% |
Energy Intake kcal/kg | 17.2 ± 9.0 | 17.0 ± 10.0 | 15.91 ± 11.1 |
Protein Intake g/kg/d | 0.6 ± 0.34 | 0.5 ± 0.4 | 0.56 ± 0.44 |
Varible/Sex | Normal N (m/f) 1/126 | Average N(m/f) 70/20 | Poor N (m/f) 88/47 | Anorexic N (m/f) 64/36 |
---|---|---|---|---|
Protein g/kg /Male | 0.79 ± 0.23 | 0.58 ± 0.17 | 0.50 ± 0.20 | 0.27 ± 0.17 |
Protein g/kg /Female | 0.79 ± 0.23 | 0.56 ± 0.16 | 0.48 ± 0.15 | 0.29 ± 0.20 |
Energy cal/kg /Male | 21.57 ± 7.85 | 25 ± 3.70 | 12.36 ± 4.26 | 6.92 ± 4.36 |
Energy cal/kg /Female | 21.19 ± 5.81 | 14.67 ± 3.09 | 12.79 ± 3.92 | 7.25 ± 3.95 |
0.000), energy (p 0.000) and carbohydrate (p 0.000).
Appetite correlated with creatinine (p 0.019), dietary energy, protein, carbohydrate and fat (p 0.000) intake. BMI correlated (p 0.000) with fat, carbohydrate, energy and creatinine clearance. Creatinine clearance was positively associated with energy intake p 0.035, carbohydrate (p 0.004), body weight (p 0.000) and BMI (p 0.000). Anova showed significant difference within and between appetite groups in energy, protein, fat, carbohydrate, creatinine clearance (p 0.000) and serum albumin (p 0.025). There was significant difference in protein (p 0.026) energy intake (p 0.000) and creatinine clearance (p 0.038) within and between BMI groups.
Association of income with other parameters: Income had strong correlation with BMI (p 0.000), dietary protein (p 0.000) energy (p 0.000) and carbohydrate (p 0.000). Based on income there was significant difference between groups in energy (p 0.019), protein (p 0.031), albumin (p 0.001) and BMI (p 0.000).
PEW is a distinct condition in chronic kidney disease (CKD) patients. It is a major challenge and one of the strongest predictor of mortality in patients with CKD. PEW is multifactorial. Uremia due to decline in renal function causes reduced dietary intake, anorexia, inflammation, imbalance between anabolic and catabolic hormones and eventually poor nutritional status. These factors along with chronic infections and comorbid conditions lead to PEW [
Serum albumin is used for monitor nutritional status. Hypoalbuminemia may result from reduced protein and/or calorie intake, uremia, metabolic acidosis, albuminuria, inflammation, or infection. A cross sectional study on 52 patients demonstrated serum albumin levels < 3.7 g/dL for 3 months [
However, it is still not clear if low serum levels of albumin in patients with CKD are a surrogate of inadequate protein intake or other conditions related to PEW, such as inflammation and comorbidity [
Poor/very poor appetite was associated with lower dietary energy, protein, carbohydrate and fat (p 0.000) intake. BMI correlated (p 0.000) with fat, carbohydrate, energy and creatinine clearance. The dietary energy deficit was 16 - 17 kcals/kg/d but protein intake was according to recommended dietary intake i.e. 6.0 g/kg/d. Dietary protein and energy intakes are often reduced in maintenance haemodialysis patients. In this study, we found that dietary protein intake was below levels recommended by the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (K/DOQI) Nutrition Guidelines (0.6 g/kg/day) in those with low BMI and average to poor appetite. Energy intake fell below K/DOQI targets (>30% below K/DOQI recommendations of 30 - 35 kcal/kg/day), particularly among those with poorer appetite. Therefore, more detailed nutritional assessments are needed in future to help detect PEM.
Diminished appetite was also associated with decreased concentrations of biochemical markers of nutritional status such as serum albumin and serum creatinine, and with anthropometric markers. Our results confirm and extend previously published work [
In our study income had strong correlation with BMI (p 0.000), dietary protein (p 0.000), energy (p 0.000) and carbohydrate (p 0.000). Based on income there was significant difference among groups in energy (p 0.019), protein (p 0.031), albumin (p 0.001) and BMI (p 0.000).
Very few studies have investigated independent associations between appetite and clinical outcomes. The results of the study by Kalantar-Zadeh et al. found significant and much larger effects (greater than 2-fold) after testing for linear mortality effects across four appetite categories (i.e. very good, good, fair, and poor), and nearly a 5-fold effect after dichotomizing the categories into two groups [i.e. normal (very good and good) and anorexic (fair and poor)] [
This study has shown that when oral dietary intake from regular meals cannot maintain adequate nutritional status, nutritional supplementation should be administered orally, enterally, or parenterally. Nutritional supplementation has been shown to be effective in replenishing protein and energy stores. Appetite stimulants, anti- inflammatory interventions, and newer anabolic agents are emerging as novel therapies [
Weakness of the study: This was a one point cross sectional study and patients were not followed up for subsequent changes in nutritional intake. The true effects of the impact of diminished appetite on the variables studied may be underestimated.
Conclusion: As renal function declines, appetite worsens and dietary intake decreases. Energy intake is significantly low in all groups. Low income is a risk factor for PEW in CKD. Timely and effective dietary interventions and nutritional support should correct PEW and improve outcomes in patients with CKD. Nutritional assessment is important at the time of presentation of patient to a nephrologist, followed by periodical (monthly or quarterly) assessment improvement or deterioration of existing PEW. Careful dietary intervention advising high energy oral nutritional supplements should be advised for increasing serum albumin concentration if protein intake is appropriate.
Anita Saxena,Amit Gupta, (2015) Association of Protein Energy Wasting with Income in CKD Stage 3 Patients. World Journal of Engineering and Technology,03,45-51. doi: 10.4236/wjet.2015.33B008