David B. Cockram

Stature prediction equations for elderly non-Hispanic white, non-Hispanic black, and Mexican-American persons developed from NHANES III data.

OBJECTIVE To develop new, nationally representative equations to predict stature for racial/ethnic groups of the elderly population in the United States. DESIGN Anthropometric data for stature, knee height, and sitting height for adults aged 60 years or older were collected from a sample of persons in the third National Health and Nutrition Examination Survey (1988-1994), a national probability sample of the US population. SUBJECTS A gender- and racial/ethnic-stratified sample of 4,750 persons from the US population (1,369 non-Hispanic white men, 1,472 non-Hispanic white women, 474 non-Hispanic black men, 481 non-Hispanic black women, 497 Mexican-American men, 457 Mexican-American women) aged 60 years or older participated in this study. STATISTICAL ANALYSES Sampling weights were used to adjust the individual data to account for unequal probabilities of selection, nonresponse, and coverage errors so that all individual data used in these analyses represented national probability estimates. Regression analysis was performed to predict stature in each gender and ethnic group, and the results were cross-validated. RESULTS Stature prediction models using knee height and age and sitting height and age were evaluated for each gender and racial/ethnic group. The equations with knee height and age were selected on the basis of root mean square error and pure errors in cross-validation and on the accuracy and validity of measures of knee height over sitting height. Results of these regressions, including regression coefficients, standard errors of the coefficients, multiple correlation coefficients, root mean square error, and the standard error for the individual for the final equations, are presented. CONCLUSIONS New stature prediction equations using knee height and age are presented for non-Hispanic white, non-Hispanic black and Mexican-American elderly persons from current nationally representative data. These equations should be applied when a measure of stature cannot be obtained, for example, for persons with amputations of the leg, or with spinal curvature or who are confined to bed. Predicted stature values are acceptable surrogates in nutritional indexes.

Effects of dietary intake, appetite, and eating habits on dialysis and non-dialysis treatment days in hemodialysis patients: cross-sectional results From the HEMO study

OBJECTIVE To evaluate differences between dietary energy intake (DEI), dietary protein intake (DPI), appetite, dietary patterns, and eating habits during dialysis treatment days (DD) and non-dialysis treatment days (NDD) in 1,901 adults receiving maintenance hemodialysis who were enrolled in the baseline phase of the National Institutes of Health-sponsored Hemodialysis (HEMO) study. DESIGN A cross-sectional analysis of participants at baseline (before randomization). SETTING Fifteen clinical centers across the United States. MEASUREMENTS DEI, DPI, and self-reported assessment of appetite, dietary patterns, and eating habits. RESULTS For the entire study cohort, total mean (+/- SD) DEI (1,566 +/- 636 kcal/day) and weight-adjusted DEI (23.2 +/- 9.5 kcal/kg/day) were significantly higher (P <.0001) on NDD than on DD (1,488 +/- 620 kcal/day and 22.2 +/- 9.6 kcal/kg/day), respectively. Similarly, DPI was significantly higher (P <.0001) on NDD (65.0 +/- 29.0 g/day and 0.96 +/- 0.43 g/kg/day) than on DD (60.2 +/- 26.5 g/day and 0.90 +/- 0.41 g/kg/day). On DD and NDD, the mean weight-adjusted DEI for the entire cohort was less than the HEMO study standard of care (SOC) of > or =28 kcal/kg/day, whereas on NDD, several subgroups reported dietary protein intakes that were closer to the studys SOC. These included men, patients under 50 years of age, nonblack participants, those without diabetes, those with a normal or mild Index of Co-Existing Disease score, and those on dialysis for more than 5 years. Protein and energy intakes declined with worsening self-reported appetites in both DD and NDD after adjusting for other subgroup effects. CONCLUSION Dietary energy and protein intakes of HEMO study participants were lower on DD than on NDD, and also lower than the SOC on both days, particularly with regard to energy intake. People receiving maintenance hemodialysis should be counseled to consume adequate amounts of energy and protein daily, especially on DD. Practitioners should monitor closely those patients who report poor appetite and should intervene appropriately.

Use of statistical methods to estimate body composition.

Epidemiologic investigations of chronic diseases in relation to body composition require large samples. This necessitates simple, reliable, and portable measures of body composition. Bioelectrical impedance analysis (BIA) variables and selected anthropometric characteristics are frequently used to predict body composition for groups or individuals when the application of sophisticated methods is not practical. We address statistical issues pertinent to the formulation of prediction equations for body composition from BIA measures and anthropometry, and factors associated with the accuracy and precision of the prediction equations.

Safety and tolerance of medical nutritional products as sole sources of nutrition in people on hemodialysis

OBJECTIVE Establish and compare the safety and tolerance of three medical nutritional products when used as sole sources of nutrition in stable hemodialysis patients. DESIGN Prospectively randomized, controlled, single blind, parallel design. SETTING Three outpatient hemodialysis clinics. PARTICIPANTS Seventy-nine normally nourished, stable, anuric, adequately dialyzed, adult outpatients with end-stage renal disease (ESRD) and requiring thrice weekly hemodialysis. INTERVENTION A 3-week trial was conducted. During the first week, baseline medical history and physical examination, gastrointestinal symptom, urea kinetic, bowel habit, and biochemical data were collected while participants ingested their usual diet. During the last 2 weeks, the same data were collected while participants orally ingested 35 kcal/kg actual weight/d of one of three medical nutritional products as a sole source of nutrition. Products were a standard medical nutritional (EN-9527) and two renal nutritionals (EN-9528 and EN-9529). The latter product was a reformulation of EN-9528 and contained added beta-carotene and fructooligosaccharides. MAIN OUTCOME MEASURES Gastrointestinal symptoms, bowel habits (stool frequency and consistency), routine blood chemistries, urea kinetics, and normalized protein catabolic rate (nPCR) RESULTS: All three groups achieved a mean energy and protein intake of approximately 35 kcal/kg/d and 1.25 g protein/kg/d during the last 10 days of the sole source feeding period. Adherence with the formula ingestion targets was assessed using both a patient-completed product consumption log and nPCR. By intent to treat analysis, there were no changes in number or severity of gastrointestinal symptoms, stool frequency or stool consistency, or urea kinetics between the baseline week and during product consumption. In comparison to the standard formulation, the disease-specific formulations resulted in improved serum phosphorus and calcium-phosphorus product. Patients receiving the fructooligosaccharide-containing product (EN-9529), by Chi-squared analysis, had less constipation than for the comparable product without oligosaccharides (EN-9528) or the standard medical nutritional (EN-9527). CONCLUSION Use of enteral nutritionals as a sole source of nutrition is both possible and well tolerated in hemodialyzed patients. Selection of a disease-specific formulation offered advantages over a standard formulation in the management of biochemical complications of renal disease when the products were used as a sole source of nutrition.

Use of an appetite and diet assessment tool in the pilot phase of a hemodialysis clinical trial: Mortality and morbidity in hemodialysis study☆

Abstract An appetite and diet assessment tool (ADAT) was developed for the National Institutes of Health pilot study, Reduction of Morbidity and Mortality in Hemodialysis Patients, to evaluate appetite and factors affecting dietary intake in hemodialysis patients in relation to the dose of dialysis delivered and/or the flux of the dialysis membrane. Forty-seven patients completed the ADAT during baseline (28 men, mean age of 63 years; 19 women, mean age of 61 years), and 31 patients in follow-up (18 men, mean age of 63 years; 13 women, mean age of 60 years). Dietary protein and energy intakes were determined in baseline using diet diary-assisted recalls. The data presented suggest that the ADAT is a practical tool for assessing the relationship between appetite and dietary intake in hemodialysis patients. It may be used in dialysis facilities to evaluate appetite and dietary habits, and to assess the effects of changes in the patients medical condition that may impact appetite and nutritional status. The effect of delivered dose of dialysis and membrane flux will be assessed during the current full-scale study for possible effects on level of appetite and its correlation with nutritional status, morbidity, and mortality. The full-scale hemodialysis study will provide an opportunity to test the validity and reliability of the ADAT, and its applicability in future clinical trials.

Mechanical and physiologic modifiers and bioelectrical impedance spectrum determinants of body composition

Fat-free mass and total and percentage body fat were determined by dual-energy X-ray absorptiometry (DXA) and total-body and segmental impedance measures were taken at 16 frequencies from 5 to 1300 kHz in a sample of white men and women aged 18-30 y. Plots of total-body and segmental impedance against frequency for each individual indicated that the general shape of these curves was described by the same mathematical function consisting of three components-ai, bi, and ci,-that contain information derived from the individual measurements of impedance summarized across the spectrum of current frequencies. Total-body and segmental multifrequency impedance were significantly correlated with hemoglobin, hematocrit, and serum sodium, potassium, creatinine, and osmolality. Regression models of body composition with total-body or segmental impedance measures at discrete frequencies or the impedance spectrum variables were similar to corresponding findings for impedance models at 50 kHz. The segmental impedance spectrum variables for total and percentage body fat and the ratios of low- to high-frequency impedance from the trunk were significantly associated with total body fatness as measured by DXA.

Selenate-Supplemented Nutritional Formula Increases Plasma Selenium in Hemodialysis Patients

OBJECTIVE The purpose of this study was to determine the short-term effect of feeding selenium-supplemented formulas on the selenium status of end-stage renal disease patients on hemodialysis. DESIGN AND SETTING The prospective, randomized, single-blind study of parallel design was conducted at three hemodialysis clinics. PATIENTS A total of 79 hemodialysis patients were randomly assigned into one of three groups. INTERVENTION Liquid nutritional formula supplemented with either selenite (28 microg Se/8 oz, n = 26), selenate (28 microg Se/8 oz, n = 26), or nonfortified (7 microg Se/8 oz, n = 27) was fed to hemodialysis patients as their sole source of nutrition for 14 days. MAIN OUTCOME MEASURE Plasma and red blood cell (RBC) selenium and glutathione peroxidase (GPX) activities were measured in predialysis blood both before (day 1) and after (day 8) a 7-day baseline period, and after subjects received the formula as the sole source of nutrition (approximately 35 kcal/kg/d) for 14 days (day 22). RESULTS Selenium intake (Mean +/- SEM, microg/d) was 134 +/- 9, 140 +/- 9, and 35 +/- 2 for patients receiving selenite-, selenate-, or non-supplemented formula, respectively. On day 22, plasma selenium (micromol/L) was greater (P <.032) in the selenate-supplemented group (1.5 +/- 0.1) compared with the nonsupplemented group (1.2 +/- 0.1), but not compared with the selenite-supplemented group (1.4 +/- 0.1). Plasma GPX activity was 44% to 60% that of healthy controls and not different among groups. RBC selenium and GPX activities were within the normal range and were not different among groups. CONCLUSION The results of this study indicate that a liquid formula supplemented with selenium as selenate is successful at maintaining selenium concentrations within normal range, as well as significantly increasing plasma selenium levels compared with nonsupplementation.

Response to an Oral Nutritional Supplement for Chronic Renal Failure Patients

■ Objective: To compare biochemical responses, nutrient intake, formula acceptability, and gastrointestinal tolerance during oral supplementation of chronic renal failure (CRF) patients using two medical nutritional products. ■ Design: Prospective, randomized, two-group, unblinded, parallel design. ■ Setting: Two university-affiliated hospitals. ■ Patients: Eighteen CRF patients (4 caucasian/14 African-American; 5 female/13 male) at risk for malnutrition but without evidence of abnormal nutrient metabolism. ■ Intervention: Oral supplementation using either clinical product EN-8915 or Polycose Glucose Polymers (Ross Products Division, Abbott Laboratories, Columbus, OH) for 4 weeks at a rate of 10 kcal/kg · d −1 . ■ Main outcome measures: Blood chemistries, self-reported nutrient intake and gastrointestinal (GI) tolerance, and sensory evaluation data. ■ Results: Both products increased energy intake by approximately 10 kcal/kg · d −1 without influencing gastrointestinal tolerance during 4 weeks of oral supplementation. Protein, vitamin, and mineral intakes were higher in patients ingesting the clinical product than Polycose. Blood chemistries were unchanged. ■ Conclusion: Short-term oral supplementation with either clinical product EN-8915 (a similar product is now marketed as Suplena Specialized Liquid Nutrition) or Polycose effectively increased energy intake. GI tolerance was excellent for both products.

Nutrition Assessment in Chronic Kidney Disease

Comprehensive nutrition assessments are comprised of an evaluation of the individual’s body composition, biochemical tests, dietary intake and habits, and clinical profile. Integration of these methodologies is used to guide appropriate medical nutrition therapy and to monitor responses to therapeutic nutrition interventions. This chapter reviews (i) common biochemical tests used for assessment of nutritional and inflammatory status; (ii) dietary intake methodologies that provide the data needed to improve nutritional status and quality of life among patients with chronic kidney disease (CKD); (iii) body composition assessment methods useful in the CKD population which can facilitate the prescription and monitoring of appropriate clinical and nutritional therapies; and (iv) nutrition physical assessment techniques with illustrations of physical manifestations of nutrient deficiencies and excesses with a specific focus on patients with CKD.

Stature Prediction Equations Using Knee Height for Elderly Americans from NHANES III (1988–94)

Abstract LEARNING OUTCOME: To present nationally representative equations for predicting stature in eldery non-hispanic whites, blacks and Mexican Americans for use in nutritional indices. Predicted values for stature are frequently needed for elderly persons in order to apply equations for estimating basal energy expenditure, subsequent nutrient needs and to calculate indices of nutritional status such as BMI. Anthropometric data for stature, knee height (knht) and sitting height were collected from a sex- and racial/ethnic-stratified sample of 4750 persons from the U.S. population (1369 non-Hispanic White men, 1472 non-Hispanic White women; 474 non-Hispanic Black men, 481 non-Hispanic Black women; 497 Mexican American men, 457 Mexican American women) 60 years of age or older in the NHANES III (1988-94). Sampling weights were used to adjust the individual data to account for unequal probabilities of selection, for non response and coverage errors to represent national probability estimates. Regression analysis was performed to predict stature in each sex and ethnic group, and the results cross validated. In the development of the new equations, the statistical model with knee height and age as predictor variables was chosen the best stature prediction equation in each sex-and racial/ethnic group. Significant regression estimates (p 2 , RMSE, and the standard error for the individual (SEI) for the equations are presented in each sex- and racial/ethnic-specific group. This study presents new stature prediction equations for non-Hispanic White, non-Hispanic Black and Mexican American elderly persons developed from current nationally representative data. Supported by Ross Products Division, Abbott Laboratories, Columbus, OH, and by NIH grants HD-12252, HD-27023 and HL53404.