Angela Madden

Body composition and morphological assessment of nutritional status in adults: a review of anthropometric variables

Evaluation of body composition is an important part of assessing nutritional status and provides prognostically useful data and an opportunity to monitor the effects of nutrition-related disease progression and nutritional intervention. The aim of this narrative review is to critically evaluate body composition methodology in adults, focusing on anthropometric variables. The variables considered include height, weight, body mass index and alternative indices, trunk measurements (waist and hip circumferences and sagittal abdominal diameter) and limb measurements (mid-upper arm and calf circumferences) and skinfold thickness. The importance of adhering to a defined measurement protocol, checking measurement error and the need to interpret measurements using appropriate population-specific cut-off values to identify health risks were highlighted. Selecting the optimum method for assessing body composition using anthropometry depends on the purpose (i.e. evaluating obesity or undernutrition) and requires practitioners to have a good understanding of both practical and theoretical limitations and to be able to interpret the results wisely.

The potential role of dual-energy X-ray absorptiometry in the assessment of body composition in cirrhotic patients.

Very little information is available on body composition in patients with cirrhosis. Difficulties arise in studying these patients because they tend to retain fluid and this results in changes in tissue density and in the hydration fraction of fat-free mass. As the classic body composition techniques rely on the assumption that these variables remain constant, use of these methods will result in either under- or overestimates of body composition variables. Use of multicomponent models, employing two or more measurement techniques, will obviate the need for some of the assumptions inherent in the use of single techniques, thereby increasing the accuracy of the assessments without loss of precision. Dual-energy x-ray absorptiometry can be used to measure total body bone mineral, fat, and fat-free soft tissue mass. In healthy individuals excellent agreement is observed between data obtained using this technique and data obtained from the more established reference methods. However, the degree to which the absorptiometry measurements of soft tissue are sensitive to the hydration is not known. Thus, in order to assess this method of body composition analysis in patients with chronic liver disease, a multicomponent model must be devised which incorporates the absorptiometry technique and allows cross-validation of the individual component measures.

The estimation of body height from ulna length in healthy adults from different ethnic groups

BACKGROUND   Assessments of nutritional status frequently incorporate a measure of height to evaluate a persons relative thinness or fatness. Because height is often difficult to quantify, it may be predicted from alternative anthropometric measurements, including ulna length. Little information is available about the accuracy of these predictions in an ethnically diverse population. The present study aimed to evaluate published equations for predicting height from ulna length in adults from different ethnic groups. METHODS   Ulna length and standing height were measured in a gender-stratified sample of 60 Asian, 69 Black and 65 White healthy volunteers, aged 21-65 years. Height was predicted from ulna length using the Malnutrition Universal Screening Tool (MUST) equations and compared against the measured values. Linear regression analysis was used to develop equations to estimate height from ulna length and to explore the relationship between height and ulna length in subgroups. RESULTS   The mean (SD) age for Asian, Black and White in men was 31.7 (11.0), 32.0 (10.3) and 38.6 (12.5) years and in women was 26.2 (5.4), 32.6 (8.9) and 35.7 (11.7); the mean (SD) height in men was 170.9 (5.2), 178.1 (7.3) and 176.3 (7.7) cm and in women was 157.7 (4.7), 164.0 (5.9) and 163.7 (6.2) cm. Ulna length and measured height were significantly correlated among all subgroups, except Asian women (r=0.11, P=0.57). The mean (SD) difference between predicted and measured height showed significant overestimates for Asian and Black men [4.0 (4.8) and 6.7 (5.3) cm] and Asian and Black women [6.4 (4.9) and 4.4 (4.9) cm] but not for White men and women. CONCLUSIONS   The MUST equations for predicting height from ulna length in healthy adults should be used with some caution among ethnically diverse populations, particularly in Asian women.

Evaluation of a Phosphate Management Protocol to Achieve Optimum Serum Phosphate Levels in Hemodialysis Patients

OBJECTIVE To evaluate the effectiveness of a protocol designed to optimize serum phosphate levels in patients undergoing regular hemodialysis (HD). DESIGN Randomized, controlled trial. SETTING Hemodialysis units at Barts and the London NHS Trust and satellite units. PATIENTS Thirty-four clinically stable adults undergoing regular HD with a serum phosphate level >1.8 mmol/L on at least one occasion within 4 months of starting the study. INTERVENTION Management of serum phosphate using a specially designed phosphate management protocol during a 4-month study period implemented by a renal dietitian and renal pharmacist compared with standard practice. MAIN OUTCOME MEASURE Change in serum phosphate levels in both groups after 4 months. RESULTS Patients managed using the phosphate management protocol had a significantly greater reduction in serum phosphate levels compared with patients receiving standard practice (-0.22 +/- 0.67 mmol/L vs. +0.19 +/- 0.32 mmol/L, P = 0.03). CONCLUSION The phosphate management protocol was effective, and its implementation was associated with significantly better serum phosphate control in patients undergoing regular HD.

Improving clinical outcome in patients with intestinal failure using individualised nutritional advice.

BACKGROUND Patients with intestinal failure are required to adhere to a complex regimen. Written information may increase knowledge leading to improvements in clinical outcomes. The present study aimed to evaluate the effectiveness of nutrition advice incorporating the use of a booklet. METHODS Each patient completed a questionnaire evaluating their knowledge of the regime and quality of life and kept a diet and gastrointestinal output diary. The diary was assessed and they were given the booklet with a verbal explanation tailored to individual requirements. The booklet explained the causes of intestinal failure, diet and fluid recommendations in relation to intestinal anatomy, information on medications and long-term monitoring. Patients were reassessed at their next appointment using the same tools. The primary endpoint was an improvement in knowledge. Secondary endpoints were an improvement in oral nutritional intake, nutritional status, quality of life and the content of home parenteral nutrition. RESULTS Forty-eight patients completed the study. Knowledge improved significantly after dietetic intervention in association with the provision of the booklet (P < 0.001). Oral energy (P = 0.04) and fat (P = 0.003) intake increased with an improvement in body mass index (P = 0.02). Patients on home parenteral nutrition showed a reduction in parenteral energy (P = 0.02), nitrogen (P = 0.003), volume (P = 0.02) and frequency (P = 0.003). CONCLUSIONS A booklet for patients with intestinal failure in conjunction with personalised dietary counselling improves knowledge and clinical outcomes.

Marketing foods to children : a comparison of nutrient content between children's and non-children's products

OBJECTIVE The predominance of marketing of products high in fat, sugar and/or salt to children has been well documented and implicated in the incidence of obesity. The present study aimed to determine whether foods marketed to children in UK supermarkets are nutritionally similar to the non-childrens equivalent, focusing on food categories that may be viewed as healthier options. DESIGN Nutritional data were collected on yoghurts (n 147), cereal bars (n 145) and ready meals (n 144) from seven major UK supermarkets and categorised as childrens or non-childrens products based on the characteristics, promotional nature or information on the product packaging. Fat, sugar and salt content was compared per 100 g and per recommended portion size. SETTING UK. RESULTS Per 100 g, childrens yoghurts and cereal bars were higher in total sugars, fat and saturated fat than the non-childrens; this was significant for all except sugar and total fat in cereal bars. Per portion these differences remained, except for sugars in yoghurts. Conversely childrens ready meals were significantly lower in these nutrients per portion than non-childrens, but not when expressed per 100 g. Childrens yoghurts and ready meals had significantly lower sodium content than non-childrens both per portion and per 100 g. CONCLUSIONS Significant differences between the nutritional composition of childrens and non-childrens products were observed but varied depending on the unit reference. A significant number of products marketed towards children were higher in fat, sugar and salt than those marketed to the general population.

A double-blind, randomized, controlled crossover trial of glutamine supplementation in home parenteral nutrition

Objective:Studies suggest clinical benefit of glutamine-supplemented parenteral nutrition. The aim was to determine if the inclusion of 10 g of glutamine as part of the nitrogen source of home parenteral nutrition (HPN) reduces infectious complications.Subjects/Methods:Thirty-five patients on HPN were recruited and 22 completed the study. Patients were randomized to receive either standard HPN or glutamine-supplemented HPN. Patients were assessed at randomization, 3 and 6 months later then they were crossed over to the alternative HPN and reassessed at 3 and 6 months. Assessments included plasma amino acid concentrations, intestinal permeability and absorption, nutritional status, oral and parenteral intake, quality of life, routine biochemistry and haematology.Results:No difference was seen between the groups at randomization. No difference was detected between the treatment phases for infective complications (55% in the standard treatment phase and 36% in the glutamine-supplemented phase P=0.67). There were no differences in nutritional status, intestinal permeability, plasma glutamine concentrations or quality of life.Conclusion:Although limited by the sample size, the study has shown that glutamine as part of the nitrogen source of parenteral nutrition can be given to patients on HPN for 6 months without any adverse effects.

Body composition and functional assessment of nutritional status in adults: a narrative review of imaging, impedance, strength and functional techniques

The accurate and valid assessment of body composition is essential for the diagnostic evaluation of nutritional status, identifying relevant outcome measures, and determining the effectiveness of current and future nutritional interventions. Developments in technology and our understanding of the influences of body composition on risk and outcome will provide practitioners with new opportunities to enhance current practice and to lead future improvements in practice. This is the second of a two-part narrative review that aims to critically evaluate body composition methodology in diverse adult populations, with a primary focus on its use in the assessment and monitoring of under-nutrition. Part one focused on anthropometric variables [Madden and Smith (2016) J Hum Nutr Diet 29: 7-25] and part two focuses on the use of imaging techniques, bioelectrical impedance analysis, markers of muscle strength and functional status, with particular reference to developments relevant to practice.

Changing perspectives in the nutritional management of disease.

There have been substantial changes in the nutritional management of many diseases in the last 20 years, which have been accompanied by a growing recognition of its importance. Many of the changes in clinical nutrition have been associated with the introduction of standards, clinical audit and the implementation of evidence-based practice, which has led to a re-evaluation of some established dietary interventions using a hierarchy-of-evidence approach. Although there are few randomised controlled trials on which to base such work, the examination of other, often less-robust, evidence has led to some traditional dietary interventions being modified. Examples in gastroenterology include the use of low-fat diets in gall bladder disease and the restriction of protein in hepatic encephalopathy, where the current evidence suggests that neither should be used routinely in clinical practice. Where therapeutic dietary restrictions are required, as with low-Na diets in ascites, there is very little information on how these restrictions influence total nutrient intake and, if intake is impaired, how the detrimental effects of an inadequate intake should be balanced with the therapeutic effects of restriction. Studies are required to ensure that nutritional interventions are not only effective but also free from undesirable side effects. The mode and timing of the delivery of nutritional support has also been re-evaluated and the benefits of early enteral feeding have been recognised. The delivery of dietary advice is a new area that is being considered, with practitioners in clinical nutrition using behaviour-change skills to facilitate optimum nutrition rather than simply providing patients with advice. For such developments to continue in clinical nutrition it is essential that all practice should be systematically evaluated and, where necessary, modified in the light of sound current research findings, and that gaps in our present knowledge base are identified and addressed.

Inhibition of the glycaemic response by onion: a comparison between lactose-tolerant and lactose-intolerant adults

This pilot study compared inhibition of the glycaemic response to glucose by a dietary source of quercetin glucosides (onion) in lactose-tolerant adults (n=12) and lactose-intolerant adults (n=12). We hypothesised that lactose-intolerant people (who do not express lactase) will retain intact quercetin glucosides that can inhibit glucose uptake via the glucose transporter SGLT1, whereas lactose-tolerant people (who do express lactase) will hydrolyse quercetin glucosides to free quercetin that does not inhibit glucose uptake. In a glucose tolerance test, reduction in peak glucose levels by an onion meal was higher in lactose-intolerant people than in lactose-tolerant people (44.2 versus 19.3%, P=0.04). Incremental area under the blood glucose curve was reduced more in lactose-intolerant people, but was not statistically significant (54.5 versus 42.1%, P=0.42). A diet containing quercetin glucosides may be of greater benefit for glycaemic control in lactose-intolerant people than in lactose-tolerant people.