Nutritional status of children with moderate chronic renal failure

Evaluation of Nutritional Status and Factors Related to Malnutrition in Children on CAPD

Objective

The aim of this study was to investigate the nutritional status of children on continuous ambulatory peritoneal dialysis (CAPD) and to relate it to the dose of dialysis and serum levels of inflammatory cytokines and insulin-like growth factor-1 (IGF-1).

Patients

17 CAPD patients (8 girls, 9 boys; mean age 13.1 ± 3.5 years, median 15 years) were included in the study. Anthropometric measurements and serum albumin levels were used in the evaluation of nutritional status. Serum interleukin (IL)-1β, IL-6, tumor necrosis factor α, and IGF-1 levels were determined in all CAPD patients and in a healthy control group. Weekly Kt/V and creatinine clearance (CCr) were measured to determine adequacy of dialysis.

Results

The mean dialysis period was 23.7 ± 15.2 months (median 23 months). Anthropometric measurements and serum albumin level were as follows: height 130.2 ± 15.6 cm, height standard deviation score (HtSDS) -4.2 ± 2.4, body mass index (BMI) 16.3 ± 1.6 kg/m2, body mass index standard deviation score (BMISDS) -0.8 ± 0.9, triceps skinfold thickness (TST) 4.2 ± 1.4 mm, midarm circumference (MAC) 16.21 ± 2.3 cm, upper arm muscle area (AMA) 1799.1 ± 535.7 mm2, upper arm fat area (AFA) 334.5 ± 143 mm2, and serum albumin 3.1 ± 0.7 g/dL. The BMI was above the fifth percentile in all patients; TST and MAC were below the fifth percentile in 14 patients (82.4%) and 10 patients (58.8%) respectively. The AMA was below the fifth percentile in 8 patients; however, the AFA was below the fifth percentile in all patients. Mean serum albumin level was under 3.5 g/dL in 70.5% of the children. We found significant positive correlations between BMI and Kt/V ( r = 0.69, p < 0.01), CCr ( r = 0.64, p < 0.05), and IL-6 ( r = 0.61, p < 0.01). There was an inverse correlation between BMISDS and dialysis period ( r = -0.58, p < 0.05); and between IL-6 and serum albumin ( r = -0.49, p < 0.05). A significant positive correlation between BMISDS and serum IGF-1 level ( r = 0.62, p < 0.01) was noted. We also found a significant positive correlation between serum IGF-1 level and both HtSDS ( r = 0.57, p < 0.05) and TST ( r = 0.52, p < 0.05). Significant positive correlations between AFA and CCr and IGF-1 were also noted (both r = 0.56, p < 0.05).

Conclusion

Although many factors may be responsible for malnutrition and growth retardation, we found that prolonged period of dialysis, inadequate dialysis, and low IGF-1 levels are the most important risk factors in CAPD patients.

Growth and Nutrition in Pediatric Chronic Kidney Disease

Children with chronic kidney disease (CKD) feature significant challenges to the maintenance of adequate nutrition and linear growth. Moreover, the impaired nutritional state contributes directly to poor growth. Therefore, it is necessary to consider nutritional status in the assessment of etiology and treatment of sub-optimal linear growth. The major causes of poor linear growth including dysregulation of the growth hormone/insulin-like growth factor-I (IGF-I) axis, nutritional deficiency, metabolic acidosis, anemia, renal osteodystrophy/bone mineral disease, and inflammation. This review summarizes the causes and assessment tools of growth and nutrition while providing a summary of state of the art therapies for these co-morbidities of pediatric CKD.

Compromised Diet Quality is Associated with Decreased Renal Function in Children with Chronic Kidney Disease

Nutritional status of children with chronic kidney disease (CKD) is important since it affects growth and development. This study was to investigate overall diet quality measured by nutrient intake adequacy, nutrient density, and several dietary habits in children with CKD and its relationship with clinical parameters according to glomerular filtration rate (GFR). Assessment of nutritional status and diet quality was conducted in nineteen children with CKD. Average Z-scores of height, weight and body mass index (BMI) in the participants were less than standard growth rate. Nutritional status, such as Z-scores of height (p < 0.05) and serum total protein (p < 0.05), were significantly lower in the children with GFR < 75 mL/min/1.73 m² compared to those with GFR ≥ 75 mL/min/1.73 m². Nutrition adequacy ratio of energy, thiamin, riboflavin, vitamin B₆, folate, iron, and zinc and overall diet quality were significantly poorer in the children with GFR < 75 mL/min/1.73 m². Poorer appetite and avoidance of food were observed in the children with higher blood urea nitrogen (BUN). Intakes of iron, zinc, thiamin, niacin, and vitamin B₆ were positively correlated with GFR. Intakes of calcium, potassium and folate were positively correlated with BUN, while protein intakes were negatively correlated. Overall nutrient intakes were inadequate and diet quality was decreased as kidney function was decreased. Dietary habit and appetite were also related with kidney function in this study subjects. Systemic efforts of nutritional intervention are imperative to prevent deteriorating growth and development and improve the nutritional status in children with CKD.

Nutrition in children with CRF and on dialysis

The objectives of this study are: (1) to understand the importance of nutrition in normal growth; (2) to review the methods of assessing nutritional status; (3) to review the dietary requirements of normal children throughout childhood, including protein, energy, vitamins and minerals; (4) to review recommendations for the nutritional requirements of children with chronic renal failure (CRF) and on dialysis; (5) to review reports of spontaneous nutritional intake in children with CRF and on dialysis; (6) to review the epidemiology of nutritional disturbances in renal disease, including height, weight and body composition; (7) to review the pathological mechanisms underlying poor appetite, abnormal metabolic rate and endocrine disturbances in renal disease; (8) to review the evidence for the benefit of dietetic input, dietary supplementation, nasogastric and gastrostomy feeds and intradialytic nutrition; (9) to review the effect of dialysis adequacy on nutrition; (10) to review the effect of nutrition on outcome.

Growth and body composition in children with chronic kidney disease

Growth failure is a common yet complex problem of childhood chronic kidney disease caused by multiple factors encountered due to the primary disease or secondary to the renal impairment. This review seeks to describe the various patho-physiological mechanisms contributing to growth failure in the various stages of childhood with particular emphasis on nutritional problems and endocrine dysfunction encountered whilst managing these children. In addition, we shall examine the role of body composition in chronic kidney disease, their relationship with growth and nutrition and the potential effect of abnormalities in fat mass and lean mass on long-term morbidity and mortality.

Measuring nutritional status in children with chronic kidney disease

Children with chronic kidney disease (CKD) are at risk of protein-energy malnutrition. Existing clinical practice guidelines recognize this and recommend specific methods to assess nutritional status in patients with CKD. This review summarizes the methods for nutritional assessment currently recommended in the United States for children with CKD and details the strengths and limitations of these techniques in the clinical setting. Dietary assessment, serum albumin, height, estimated dry weight, weight/height index, upper arm anthropometry, head circumference, and the protein equivalent of nitrogen appearance are reviewed. We also describe methods for body-composition assessment, such as dual-energy X-ray absorptiometry, bioelectrical impedance analysis (BIA), total body potassium, densitometry, and in vivo neutron activation analysis, pointing out some advantages and disadvantages of each. In CKD, fluid overload is the most important factor leading to misinterpretation of nutritional assessment measures. Abnormalities in the distribution of fat and lean tissue may also compromise the interpretation of some anthropometric measures. In addition, metabolic abnormalities may influence the results obtained by some techniques. Issues specific to evaluating nutritional status in the pediatric population are also discussed, including normalization of nutritional measures to body size and sexual maturity. We stress the importance of expressing body-composition measures relative to height in a population in whom short stature is highly prevalent.

Anthropometry of the trunk and extremities in nutritional assessment of children with chronic renal failure

OBJECTIVE

Comparison of anthropometric parameters of the trunk and extremities between 2 groups of children with chronic renal failure (CRF) with different levels of nutritional status and healthy controls.

DESIGN

A prospective cross-sectional study.

SETTINGS

Department of Physiology and Anthropology, University Ss. Cyril and Methodius, Skopje.

PATIENTS

Twenty-one patients with a mean age of 10.5 +/- 3.2 years (10 boys and 11 girls) with mild to moderate CRF were divided into well-nourished (chronic renal failure children [CRFC] I) and undernourished (CRFC II) children according to their nutritional status. The control group was 22 healthy children with a mean age of 10.7 +/- 3.8 years (10 boys and 12 girls). Nutritional status of the children was assessed by comparing anthropometric parameters with National Center for Health Statistics references.

INTERVENTIONS

Anthropometry.

MAIN OUTCOME MEASUREMENTS

Body weight, height, sitting height, arm and leg length, knee height, chest circumference, midarm circumference, triceps skin-fold thickness, and upper arm muscle and fat area.

RESULTS

Mean sitting height, leg length, and chest circumference were significantly lower in both the CRFC I group (67.8 +/- 3.5, 57.5 +/- 4.2, and 53.0 +/- 3.9 cm) and the CRFC II group (65.6 +/- 2.2, 56.1 +/- 4.1, and 50.6 +/- 2.7 cm) compared with the healthy controls (72.5 +/- 2.9, 61.3 +/- 3.5, and 62.4 +/- 4.1 cm, respectively). The highest significant correlations to height were for sitting height (r = +0.82, P <.05) and knee height (r = +0.72, P <.05) in CRFC I and for leg length (r = +0.74, P <.05) in CRFC II. There was no correlation between anthropometric parameters of the trunk and extremities and upper muscle and fat area in both groups of CRF children.

CONCLUSION

The sitting height, knee height, and leg length can be used in nutritional and growth assessment when it is impossible to make a reliable measurement of height in CRF children.

Hypoalbuminemia and risk of death in pediatric patients with end-stage renal disease

BACKGROUND

Although serum albumin is a marker for malnutrition and associated with a higher mortality in adult patients with end-stage renal disease (ESRD), the risk of death associated with serum albumin is unknown in pediatric patients with ESRD. We evaluated the association between serum albumin and death among pediatric patients initiating dialysis.

METHODS

Data from the United States Renal Data System (USRDS) were used to identify all patients under the age of 18 who initiated dialysis between January 1, 1995 and December 31, 1998. Using the Cox proportional hazards models, the association between serum albumin obtained 45 days prior to dialysis initiation and death was estimated, controlling for demographic factors, dialysis modality, and anthropometric measures.

RESULTS

Of 1723 patients included in the analysis, there were 93 deaths over 2953 patient-years of observation. The multivariate analysis demonstrated that each -1 g/dL difference in serum albumin between patients was associated with a 54% higher risk of death [adjusted relative risk (aRR), 1.54; 95% confidence interval (CI), 1.15 to 1.85; P=0.002]. This was independent of glomerular causes for their ESRD and other potential confounding variables.

CONCLUSIONS

Pediatric patients initiating dialysis with hypoalbuminemia are at a higher risk for death. This finding persists after adjusting for glomerular causes for ESRD and other potential confounding variables. Low serum albumin at dialysis initiation is an important marker of mortality risk in pediatric ESRD patients.

[Children with chronic renal failure: evaluation of the nutritional status and management]

Since malnutrition is a well recognized problem in children with chronic renal failure, nutritional management of these children is essential. This review describes methods for nutritional assessment and suggests guidelines for providing maximal dietary support in children with chronic renal insufficiency. Optimal nutritional management includes an adequate caloric and protein intake, a restriction of phosphorus intake and an appropriate intake of electrolytes and vitamins.

Growth plate cartilage formation and resorption are differentially depressed in growth retarded uremic rats

To characterize the modifications of growth plate in individuals with growth impairment secondary to chronic renal failure, young rats were made uremic by subtotal nephrectomy (NX) and, after 14 d, their tibial growth plates were studied and compared with those of sham-operated rats fed ad libitum (SAL) or pair-fed with NX (SPF). NX rats were growth retarded and severely uremic. Growth plate height (mean +/- SD) was much greater (P<0.05) in NX (868.4+/-85.4 microm) than SAL (570.1+/-93.5 microm) and SPF (551.9+/-99.7 microm) rats as a result of a higher (P<0.05) hypertrophic zone (661.0+/-89.7 versus 362.8+/-71.6 and 353.0+/-93.9 microm, respectively). The increased size of the growth plate was associated with a greater number of chondrocytes and modifications in their structure, particularly in the hypertrophic zone adjacent to bone. In this zone, chondrocytes of NX animals were significantly (P<0.05) smaller (12080.4+/-1158.3 microm3) and shorter (34.1+/-2.5 microm) than those of SAL (16302.8+/-1483.4 microm3 and 37.8+/-2.0 microm) and SPF (14465.8+/-1521.0 microm3 and 36.3+/-1.8 microm). The interface between the growth plate cartilage and the metaphyseal bone appeared markedly irregular in NX rats. Kinetics of chondrocytes was also modified (P<0.05) in the NX rats, which had lower cell turnover per column per day (5.4+/-0.9), longer duration of hypertrophic phase (89.0+/-15.2 h), and reduced cellular advance velocity (7.4+/-2.2 microm/h) compared with SAL (8.0+/-1.6, 32.1+/-6.7 h, and 11.3+/-2.7 microm/h) and SPF (7.2+/-1.1, 34.8+/-5.1 h, and 10.1+/-2.5 microm/h). Cell proliferation was no different among the three groups. Because the growth plates of SPF and SAL rats were substantially not different, modifications observed in the NX rats cannot be attributed to the nutritional deficit associated with renal failure. These findings indicate that chronic renal failure depresses both the activity of the growth plate cartilage by altering chondrocyte hypertrophy and the replacement of cartilage by bone at the metaphyseal end. The two processes are differentially depressed since cartilage resorption is more severely lowered than cartilage enlargement and this leads to an accumulation of cartilage at the hypertrophic zone.