Jonathan E. Rhoads Lecture. Body composition research: implications for the practice of clinical nutrition

Nutrition management in acute pancreatitis: Clinical practice consideration

Acute pancreatitis (AP) is a common gastrointestinal disease and the leading cause of hospital admission and healthcare burden among gastrointestinal disorders in many countries. Patients can present with varying degrees of inflammation and disease severity, ranging from self-limiting mild AP to devastating and fatal severe AP. Many factors contribute to malnutrition in AP, especially abnormal metabolism and catabolism related to inflammation. The concept of “pancreatic rest” is not evidence-based. There is however, emerging evidence that supports the use of oral or enteral nutrition to improve nutrition status and to reduce local and systemic inflammation, complications, and death. In mild disease, patients are generally able to initiate solid oral diet and do not require specialized nutrition care such as enteral or parenteral nutrition. In contrast, nutrition interventions are imperative in moderately severe and severe AP. The current article aims to review the latest evidence and suggest practical nutrition interventions in patients with AP, including nutrition requirements, routes of nutrition treatment, types of formula, and the role of nutritional supplements, such as glutamine, probiotics, omega-3 fatty acids, and antioxidants.

Skeletal muscle mass and adipose tissue alteration in critically ill patients

Background

Increasing numbers of studies in chronic diseases have been published showing the relationship between body composition (BC) parameters (i.e. skeletal muscle mass (SMM) and adipose tissue (AT)) and outcomes. For patients admitted to intensive care unit (ICU), BC parameters have rarely been described as a prognostic marker of outcome. The primary objective was to evaluate the relationship between body composition at ICU admission and major clinical outcomes. Secondary objectives were to assess the relationship between BC parameters and other parameters (systemic inflammatory markers, Sequential Organ Failure Assessment (SOFA) score, albumin level) at ICU admission, and between BC alterations during ICU stay and outcomes.

Patients and methods

This retrospective study enrolled 25 adult patients who had two abdominal CT scans for clinical indication: first, within 48 hours of ICU admission (initial assessment), and second, 7 to 14 days later (late assessment). Skeletal Muscle radiodensity (SMD), cross-sectional area of SMM, Visceral Adipose Tissue (VAT) and Subcutaneous Adipose Tissue (SAT) were measured at the third lumbar vertebra. Cox regression analysis was used to determine the association between these parameters and mortality.

Results

Patients’ mean age was 64.6 years. Their mean BMI was 27.7 kg/m² (SD = 6.0). ICU mortality was 36%. There was no correlation between BC parameters at initial assessment and ICU outcomes. We observed a negative correlation between SMM index and SOFA score at initial assessment (r = -0.458, p = 0.037). There was a significant loss of VAT between two CT assessments which was associated with mortality (-22.34cm² / m² in non-survivors versus -6.22 cm² / m² in survivors, p = 0.039). Loss of SMD was greater with the occurrence of an infection than without (Delta SMD = -5.642 vs +1.957, p = 0.04).

Conclusions

Our results show alterations in body composition during ICU stay with a loss of muscle quality (decreased SMD) and adipose tissue. These findings require confirmation in future studies but already show that BC assessments at ICU admission and BC alterations during ICU stay are important factors for outcome in critically ill patients.

From chemical analysis of the body...to metabolic insights provided by the new methodology

It is by no means an exaggeration to say that Dr Widdowson is one of the pioneers of body composition research and her studies in the 1940s and 1950s have laid the foundations of body composition science today. These have included both animal and human studies, although this paper will focus only on the latter. Together with Professor McCance and Christine Spray she was responsible for the analysis of three entire adult human cadavers and that of a 4-year-old child (Widdowson et al. 1951). Further work with Dr Dickerson explored the composition of specific tissues and organs of the body (Widdowson & Dickerson, 1964). These studies provide some of the best direct data on human body composition. Moreover the findings from this work form the basis of the indirect techniques which are used so widely today.

The Effect of Special Diets on Weight and Nutritional Intake in Hematological Cancer Patients: A Randomized Study

Major weight loss and taste changes are well documented in patients with hematological cancer during chemotherapy. We have previously documented, that such patients have preferences for much umami, a little sweet, sour and salt, and no bitter. We wanted to convert these results into real diets. Patients participated in two sensory pilot studies (n = 10), where dishes were tested for preferences before and after chemotherapy. From these results, four dishes were selected and tested on 32 patients in 30 days in a cross-over design. The diets resulted in a beneficial and statistically significant difference in weight development (p = 0.0008), with 1.2 ± 1.9 kg (+2%) in the intervention period and -2.8 ± 5.2 kg (-4%) in the control period. This difference persisted after sensitivity analysis (±10%) P = 0.005. However, the nutritional intake was still low in both periods, and the treatment with cytarabine turned out to be a major confounder as dosage was significantly higher in the control period.

Body Composition Analysis by Using Bioelectrical Impedance in a Young Healthy Chinese Population: Methodological Considerations

OBJECTIVE

To develop a new bioelectrical impedance analysis (BIA) model for analyzing body composition by using isotope dilution, magnetic resonance imaging (MRI), and dual-energy X-ray absorptiometry (DEXA) as the reference methods in young healthy Chinese populations.

METHODS

Thirty healthy participants were enrolled. Their body composition was analyzed using BIA and 3 reference methods. We established a model that uniformed data from 3 references methods (isotope, MRI, and DEXA) into 1 formula. This model was further validated with 209 participants.

RESULTS

The following BIA body composition adjustment model was developed: [Formula: see text], where X represents the impedance index; when K = 1, 2, and 3, Y represents total body water, fat mass, and bone mass, respectively. The prediction accuracy of this formula was 93.3%. By incorporating the data matrix, the protein mass was calculated using BIA: [Formula: see text]. In the verification part of this study, the lean body mass measured using DEXA and BIA was 43.02 ± 8.34 kg and 45.85 ± 8.81 kg, respectively. Analysis indicated that the model fit was extremely favorable ( R² = .9997, P < .001).

CONCLUSIONS

The accuracy of BIA measurement on body composition and protein mass is significantly improved by our work.

Monitoring Energy Metabolism with Indirect Calorimetry: Instruments, Interpretation, and Clinical Application

Indirect calorimetry is the best measure to guide calorie administration during nutrition support. This article presents an update of the types of currently available indirect calorimeters and reviews the recent advances that guide the clinical application of indirect calorimetry. The emphasis of this report is placed on issues that the practicing clinician can use to evaluate, interpret, and apply measurements of energy expenditure.

Fat-free mass at admission predicts 28-day mortality in intensive care unit patients: the international prospective observational study Phase Angle Project

PURPOSE

Phase angle as measured by bioelectrical impedance analysis reflects fat-free mass. Fat-free mass loss relates to worse prognosis in chronic diseases. Primary aim of this study was: to determine the association between fat-free mass at intensive care unit admission and 28-day mortality.

METHODS

Ten centres in nine countries participated in this multicentre prospective observational study. The inclusion criteria were age >18 years; expected length of stay >48 h; absence of pacemaker, heart defibrillator implant, pregnancy and lactation. Fat-free mass was assessed by measurement of the 50-kHz phase angle at admission. The primary endpoint was 28-day mortality. The area under the receiver operating characteristic curve (AUC) was used to assess prediction of 28-day mortality by fat-free mass at ICU admission. The variables associated with 28-day mortality were analysed by means of multivariable logistic regression.

RESULTS

Of the 3605 patients screened, 931 were analysed: age 61 ± 16 years, male 60 %, APACHE II 19 ± 9, body mass index 26 ± 6, day 1 phase angle 4.5° ± 1.9°. Day 1 phase angle was lower in patients who eventually died than in survivors (4.1° ± 2.0° vs. 4.6° ± 1.8°, P = 0.001). The day 1 phase angle AUC for 28-day mortality was 0.63 [0.58-0.67]. In multivariable analysis, the following were independently associated with 28-day mortality: age (adjusted odds ratio (aOR) 1.014 [95 % confidence interval 1.002-1.027], P = 0.03), day 1 phase angle (aOR 0.86 [0.78-0.96], P = 0.008), APACHE II (aOR 1.08 [1.06-1.11], P < 0.001), surgical patient (aOR 0.51 [0.33-0.79], P = 0.002), and admission for other diagnosis (aOR 0.39 [0.21-0.72], P = 0.003). A multivariable combined score improved the predictability of 28-day mortality: AUC = 0.79 [0.75-0.82].

CONCLUSION

Low fat-free mass at ICU admission is associated with 28-day mortality. A combined score improves mortality predictability.

TRIAL REGISTRATION

NCT01907347 ( http://www.clinicaltrials.gov ).

[Enteral Nutritional Support in Gastrointestinal and Liver Diseases]

Nutritional support is important because malnutrition is a major contributor to increased morbidity and mortality, decreased quality of life, increased length of hospital stay, and higher healthcare costs. Patients with gastrointestinal disease are at an increased risk of nutritional deterioration due to therapeutic dietary restriction, fasting for the diagnostic tests, loss of appetite due to anorexia or altered nutritional requirement caused by the disease itself. Therefore, it is important that gastroenterologists are aware of the nutritional status of patients and plan a treatment strategy considering patient's nutritional status. Enteral nutrition is preferred to parenteral nutrition as it is more physiologic, has fewer complications, help to prevent mucosal atrophy and maintain gut barrier function, which decrease intestinal bacterial translocation. Hence, enteral nutrition has been considered to be the most effective route for nutritional support. In this article, we will review enteral nutrition (oral nutritional supplements, enteral tube feeding) as a treatment for the patients with gastrointestinal, liver and pancreatic disease at risk of malnutrition.

Comparison of percentage body fat and body mass index for the prediction of inflammatory and atherogenic lipid risk profiles in elderly women

OBJECTIVE

To compare the clinical classification of the body mass index (BMI) and percentage body fat (PBF) for the prediction of inflammatory and atherogenic lipid profile risk in older women.

METHOD

Cross-sectional analytical study with 277 elderly women from a local community in the Federal District, Brazil. PBF and fat-free mass (FFM) were determined by dual energy X-ray absorptiometry. The investigated inflammatory parameters were interleukin 6 and C-reactive protein.

RESULTS

Twenty-five percent of the elderly women were classified as normal weight, 50% overweight, and 25% obese by the BMI. The obese group had higher levels of triglycerides and very low-density lipoproteins than did the normal weight group (P≤0.05) and lower levels of high-density lipoproteins (HDL) than did the overweight group (P≤0.05). According to the PBF, 49% of the elderly women were classified as eutrophic, 28% overweight, and 23% obese. In the binomial logistic regression analyses including age, FFM, and lipid profile, only FFM (odds ratio [OR]=0.809, 95% confidence interval [CI]: 0.739-0.886; P<0.0005) proved to be a predictor of reaching the eutrophic state by the BMI. When the cutoff points of PBF were used for the classification, FFM (OR=0.903, CI=0.884-0.965; P=0.003) and the total cholesterol/HDL ratio (OR=0.113, CI=0.023-0.546; P=0.007) proved to be predictors of reaching the eutrophic state.

CONCLUSION

Accurate identification of obesity, systemic inflammation, and atherogenic lipid profile is key to assessing the risk of cardiometabolic diseases. Classification based on dual energy X-ray absorptiometry measures, along with biochemical and inflammatory parameters, seems to have a great clinical importance, since it allows the lipid profile eutrophic distinction in elderly overweight women.

Development and current use of parenteral nutrition in critical care - an opinion paper

Critically ill patients depend on artificial nutrition for the maintenance of their metabolic functions and lean body mass, as well as for limiting underfeeding-related complications. Current guidelines recommend enteral nutrition (EN), possibly within the first 48 hours, as the best way to provide the nutrients and prevent infections. EN may be difficult to realize or may be contraindicated in some patients, such as those presenting anatomic intestinal continuity problems or splanchnic ischemia. A series of contradictory trials regarding the best route and timing for feeding have left the medical community with great uncertainty regarding the place of parenteral nutrition (PN) in critically ill patients. Many of the deleterious effects attributed to PN result from inadequate indications, or from overfeeding. The latter is due firstly to the easier delivery of nutrients by PN compared with EN increasing the risk of overfeeding, and secondly to the use of approximate energy targets, generally based on predictive equations: these equations are static and inaccurate in about 70% of patients. Such high uncertainty about requirements compromises attempts at conducting nutrition trials without indirect calorimetry support because the results cannot be trusted; indeed, both underfeeding and overfeeding are equally deleterious. An individualized therapy is required. A pragmatic approach to feeding is proposed: at first to attempt EN whenever and as early as possible, then to use indirect calorimetry if available, and to monitor delivery and response to feeding, and finally to consider the option of combining EN with PN in case of insufficient EN from day 4 onwards.

Pediatric burn injuries

Pediatric burns comprise a major mechanism of injury, affecting millions of children worldwide, with causes including scald injury, fire injury, and child abuse. Burn injuries tend to be classified based on the total body surface area involved and the depth of injury. Large burn injuries have multisystemic manifestations, including injuries to all major organ systems, requiring close supportive and therapeutic measures. Management of burn injuries requires intensive medical therapy for multi-organ dysfunction/failure, and aggressive surgical therapy to prevent sepsis and secondary complications. In addition, pain management throughout this period is vital. Specialized burn centers, which care for these patients with multidisciplinary teams, may be the best places to treat children with major thermal injuries. This review highlights the major components of burn care, stressing the pathophysiologic consequences of burn injury, circulatory and respiratory care, surgical management, and pain management of these often critically ill patients.

The role of B vitamins in the management of heart failure

Heart failure (HF) is the leading cause of morbidity and mortality in industrialized countries, creating a significant burden on both the healthcare system and quality of life. Research efforts continue to explore new pharmaceutical or surgically based approaches to HF management, but the role of nutrition as an adjunct therapy has been largely ignored. Elderly age, anorexia, malabsorption, premature satiety, and disease severity are among the factors identified as contributing to reduced nutrient intakes in patients with HF. These factors suggest that patients with HF are at increased risk of multiple-nutrient deficiencies, including B vitamins. B vitamins may be of particular therapeutic interest because of their key roles as cofactors in energy-producing pathways. Recently, impaired stores of high-energy compounds have been linked with myocardial dysfunction and prognosis in patients with HF. Therefore, deficiencies of B vitamins might contribute to reduced energy stores and disease progression. This review summarizes the existing literature both with respect to the prevalence of B vitamin deficiency as well as evidence from supplementation trials in patients with HF. The findings suggest that most of the literature in this area has focused on thiamin deficiency in patients with HF, whereas other B vitamins remain largely unstudied. Although few sporadic trials suggest a role for B vitamins in the management of HF, none are conclusive. Therefore, there is a need for larger, more robust trials to assist in defining the B vitamin requirements as well as the impact of supplementation on both morbidity and mortality in patients with HF.

Body composition: why, when and for who?

Body composition reflects nutritional intakes, losses and needs over time. Undernutrition, i.e. fat-free mass (FFM) loss, is associated with decreased survival, worse clinical outcome and quality of life, as well as increased therapy toxicity in cancer patients. In numerous clinical situations, such as sarcopenic obesity and chronic diseases, the measurement of body composition with available methods, such as dual-X ray absorptiometry, computerized tomography and bioelectrical impedance analysis, quantifies the loss of FFM, whereas body weight loss and body mass index only inconstantly reflect FFM loss. The measurement of body composition allows documenting the efficiency of nutrition support, tailoring the choice of disease-specific and nutritional therapies and evaluating their efficacy and putative toxicity. Easy-to-use body composition methods integrated to the routine of care allow sequential measurements for an initial nutritional assessment and objective patients follow-up. By allowing an earlier and objective management of undernutrition, body composition assessment could contribute to reduce undernutrition-induced morbidity, worsening of quality of life, and global health care costs by a timely nutrition intervention.

The evaluation of body composition: a useful tool for clinical practice

Undernutrition is insufficiently detected in in- and outpatients, and this is likely to worsen during the next decades. The increased prevalence of obesity together with chronic illnesses associated with fat-free mass (FFM) loss will result in an increased prevalence of sarcopenic obesity. In patients with sarcopenic obesity, weight loss and the body mass index lack accuracy to detect FFM loss. FFM loss is related to increasing mortality, worse clinical outcomes, and impaired quality of life. In sarcopenic obesity and chronic diseases, body composition measurement with dual-energy X-ray absorptiometry, bioelectrical impedance analysis, or computerized tomography quantifies the loss of FFM. It allows tailored nutritional support and disease-specific therapy and reduces the risk of drug toxicity. Body composition evaluation should be integrated into routine clinical practice for the initial assessment and sequential follow-up of nutritional status. It could allow objective, systematic, and early screening of undernutrition and promote the rational and early initiation of optimal nutritional support, thereby contributing to reducing malnutrition-induced morbidity, mortality, worsening of the quality of life, and global health care costs.

Military nutrition: maintaining health and rebuilding injured tissue

Food and nutrition are fundamental to military capability. Historical examples demonstrate that a failure to supply adequate nutrition to armies inevitably leads to disaster; however, innovative measures to overcome difficulties in feeding reap benefits, and save lives. In barracks, UK Armed Forces are currently fed according to the relatively new Pay As You Dine policy, which has attracted criticism from some quarters. The recently introduced Multi-Climate Ration has been developed specifically to deal with issues arising from Iraq and the current conflict in Afghanistan. Severely wounded military personnel are likely to lose a significant amount of their muscle mass, in spite of the best medical care. Nutritional support is unable to prevent this, but can ameliorate the effects of the catabolic process. Measuring and quantifying nutritional status during critical illness is difficult. A consensus is beginning to emerge from studies investigating the effects of nutritional interventions on how, what and when to feed patients with critical illness. The Ministry of Defence is currently undertaking research to address specific concerns related to nutrition as well as seeking to promote healthy eating in military personnel.

Hospital malnutrition: prevalence, identification and impact on patients and the healthcare system

Malnutrition is a debilitating and highly prevalent condition in the acute hospital setting, with Australian and international studies reporting rates of approximately 40%. Malnutrition is associated with many adverse outcomes including depression of the immune system, impaired wound healing, muscle wasting, longer lengths of hospital stay, higher treatment costs and increased mortality. Referral rates for dietetic assessment and treatment of malnourished patients have proven to be suboptimal, thereby increasing the likelihood of developing such aforementioned complications. Nutrition risk screening using a validated tool is a simple technique to rapidly identify patients at risk of malnutrition, and provides a basis for prompt dietetic referrals. In Australia, nutrition screening upon hospital admission is not mandatory, which is of concern knowing that malnutrition remains under-reported and often poorly documented. Unidentified malnutrition not only heightens the risk of adverse complications for patients, but can potentially result in foregone reimbursements to the hospital through casemix-based funding schemes. It is strongly recommended that mandatory nutrition screening be widely adopted in line with published best-practice guidelines to effectively target and reduce the incidence of hospital malnutrition.

Relationship between serum protein and mortality in adults on long-term hemodialysis: exhaustive review and meta-analysis

The aim of this exhaustive review and meta-analysis was to explore the relation among serum protein, inflammatory markers, and all-cause and cardiovascular mortalities in adult patients on maintenance hemodialysis. We searched the Medline, Science Citation Index, Academic Search Premier, Cochrane Library, and Embase electronic data bases. Data extraction and quality assessment were done independently by two reviewers and results were pooled using the random effects model. Cochran's Q was used to identify heterogeneity and a funnel plot was used for assessment of publication bias. A meta-analysis was performed on 38 studies (265 330 patients) reporting on serum proteins, inflammatory markers, and mortality. A significant inverse relation was found between serum albumin and all-cause (hazard ratio [HR] 0.7038, 95% confidence interval [CI] 0.6367-0.7781) and cardiovascular (HR 0.8726, 95% CI 0.7909-0.9628) mortalities, with a significantly stronger relation with all-cause mortality (P=0.0014). Pooled results for C-reactive protein showed a weak but significant direct relation with all-cause mortality (HR 1.0322, 95% CI 1.0151-1.0496), but there was not a significant relation between C-reactive protein and cardiovascular mortality (HR 1.0172, 95% CI 0.9726-1.0639). A high degree of heterogeneity was identified among studies especially in the case of all-cause mortality. An asymmetrical funnel plot for serum albumin is suggestive of publication bias. From the meta-analysis it is concluded that serum albumin showed a significant inverse relation with all-cause and cardiovascular mortalities but the relation between prealbumin and all-cause mortality was not significant. C-reactive protein showed a significant direct relation with all-cause mortality but not with cardiovascular mortality. The potential adverse effects of malnutrition and infections in relation to mortality highlight the need for continued treatment of infections and correction of malnutrition in patients on dialysis.

L-alanyl-L-glutamine-supplemented parenteral nutrition decreases infectious morbidity rate in patients with severe acute pancreatitis

BACKGROUND

The effect of parenteral GLN on recovery from severe acute pancreatitis has not been thoroughly investigated. The aims of this study were to determine whether parenteral GLN improves nutrition status and immune function, and to determine its ability to reduce morbidity and mortality in patients with this condition.

METHODS

In a randomized clinical trial, 44 patients with severe acute pancreatitis were randomly assigned to receive either standard PN (n = 22) or l-alanyl-l-glutamine-supplemented PN (n = 22) after hospital admission. Nitrogen balance, counts of leukocytes, total lymphocytes, and CD4 and CD8 subpopulations, and serum levels of immunoglobulin A, total protein, albumin, C-reactive protein, and serum interleukin (IL)-6 and IL-10 were measured on days 0, 5, and 10. Hospital stay, infectious morbidity, and mortality were also evaluated.

RESULTS

Demographics, laboratory characteristics, and pancreatitis etiology and severity at entry to the study were similar between groups. The study group exhibited significant increases in serum IL-10 levels, total lymphocyte and lymphocyte subpopulation counts, and albumin serum levels. Nitrogen balance also improved to positive levels in the study group and remained negative in the control group. Infectious morbidity was more frequent in the control group than in the study group. The duration of hospital stay was similar between groups, as was mortality.

CONCLUSION

The results suggest that treatment of patients with GLN-supplemented PN may decrease infectious morbidity rate compared with those who treated with nonenriched PN.

Short-term nutritional implications of total gastrectomy for malignancy, and the impact of parenteral nutritional support

AIMS

To report on peri-operative nutritional status in gastric cancer patients undergoing total gastrectomy, and to examine the role of post-operative parenteral nutrition.

METHODS

Retrospective study of prospectively collected data on 90 consecutive patients who underwent total gastrectomy for malignancy.

RESULTS

At diagnosis 46% of patients reported clinically severe weight loss, and dietary intake was inadequate in 72% of patients. Post-operatively 42% were given total parenteral nutrition (TPN) and 53% were given intravenous fluids (IVF) alone. TPN patients spent a mean of 13.6 days on nutrition support versus IVF patients who spent a mean of 9.2 days without any form of nutrition. IVF patients lost significantly more weight in hospital than TPN patients (5.2 kg versus 3.1 kg, p=0.008). 69% of IVF patients lost severe amount of weight versus 34% in the TPN group (p=0.01). Post-discharge, IVF patients continued to lose significantly more weight than those given TPN post-operatively (7.5 kg versus 2.9 kg, p=0.01) corresponding to 10.5% of their body weight from discharge to follow up versus 4.9% for TPN group (p=0.014). From pre-illness to follow up, patients lost an average of 15.5 kg--IVF patients lost 17.8 kg versus 9.6 kg in TPN (p<0.01). There was no difference in post-operative complications between the groups; however, patients with >10% weight loss had a significantly higher rate of complications and a significantly higher mortality rate than patients who lost <10% body weight (26.2% versus 51.9%, p=0.036 and 11.1% versus 0%, p=0.027, respectively). On multivariate logistic regression analysis >10% weight loss at diagnosis was the only predictive factor of post-operative complications OR 3.1 (95% CI 1.0-9.6), p=0.04).

CONCLUSIONS

There is a high prevalence of malnutrition in gastric cancer patients undergoing surgery. Total gastrectomy is associated with dramatic weight loss, which continues beyond the surgeon's view post-discharge, with patients losing an average of 15.5 kg by 3-month follow up. Provision of nutrition support in the form of TPN post-operatively significantly reduces in-hospital weight loss and also helps to attenuate further weight loss post-discharge.

Use of bioelectrical impedance analysis to assess body composition in rural Gambian children

OBJECTIVE

To validate the Tanita BC-418MA Segmental Body Composition Analyser and four-site skinfold measurements for the prediction of total body water (TBW), percentage fat-free mass (%FFM) and percentage body fat (%BF) in a population of rural Gambian children.

SUBJECTS/METHODS

One hundred and thirty-three healthy Gambian children (65 males and 68 females). FFM estimated by the inbuilt equations supplied with the Tanita system was assessed by comparison with deuterium oxide dilution and novel prediction equations were produced. Deuterium oxide dilution was also used to develop equations for %BF based on four-site skinfolds (biceps, triceps, subscapular and suprailiac).

RESULTS

The inbuilt equations underestimated FFM compared to deuterium oxide dilution in all the sex and age categories (P<0.003), with greater accuracy in younger children and in males. The best prediction of %FFM was obtained from the variables height, weight, sex, impedance, age and four skinfold thickness measurements (adjusted R(2)=0.84, root mean square error (MSE)=2.07%).

CONCLUSIONS

These data suggest that the Tanita instrument may be a reliable field assessment technique in African children, when using population and gender-specific equations to convert impedance measurements into estimates of FFM.

Impedance index or standard anthropometric measurements, which is the better variable for predicting fat-free mass in sick children?

AIM

To compare the predictive value of impedance index (ZI, height2/impedance) with anthropometric measurements for estimating fat-free mass (FFM).

METHODS

FFM of 120 white paediatric children (46 males, 74 females), aged 2.5-18 years was measured by using dual energy X-ray absorptiometry. Weight, height, mid-upper arm circumference (MUAC), skinfold thickness (biceps, triceps, subscapular and suprailiac) and bioelectrical impedance were also obtained. Stepwise multiple regression analysis and residual plots were performed to determine the most significant variables to predict FFM.

RESULTS

The single best predictor of FFM was ZI, which explained 96.2% of the variance in FFM (r = 0.981, SEE = 2.15 kg). Addition of weight to the model containing ZI increased the explained variance of FFM to 96.6% (r = 0.983, SEE = 2.03 kg). BMI and MUAC were the poorest predictors of FFM: r = 0.422, SEE = 10.2 kg and r = 0.621, SEE = 8.93 kg, respectively.

CONCLUSION

Impedance index is a more significant single predictor of FFM than other anthropometric measurements. The predictive accuracy of bioelectrical impedance analysis-based prediction equations for FFM was improved by addition of weight.

Nutritional assessment

Hospital-based malnutrition continues to be an important comorbidity affecting clinical outcomes. Knowledge of performing an appropriate nutrition assessment and implementing a rational nutrition therapy should be part of any patient's hospital plan of care. Familiarity with nutrition assessment scoring systems and nutrition assessment tools should be part of any gastroenterologist's expertise. Assessment of a patient's caloric and protein needs should be part of any hospital patient's clinical evaluation.

Early enteral nutrition in severe acute pancreatitis: a prospective randomized controlled trial comparing nasojejunal and nasogastric routes

PURPOSE

Enteral nutrition (EN) is effective, easy to provide, cheaper, and associated with fewer complications in comparison with parenteral nutrition in severe acute pancreatitis (SAP). However, the nasogastric (NG) route for enteral supplements still remains to be established, and most studies have used the nasojejunal (NJ) route. The purpose of this study was to compare early NJ with NG feeding in SAP.

PATIENTS AND METHODS

A total of 31 patients with SAP were randomized to feeding by either NG (15 patients) or NJ (16 patients). A semi-elemental formula was used through an enteral tube in both groups. Nutritional parameters (anthropometry, serum prealbumin and albumin levels) were recorded at baseline and after 7 days. Recurrence of pain and tolerance of feeding was noted.

RESULTS

Recurrence of pain occurred in only 1 patient each in the 2 groups. Diarrhea occurred in 3 and 4 patients in the NJ and NG groups, respectively. There were 4 deaths in the NJ group and 5 in the NG group. Two patients in the NJ group and 1 in the NG group underwent surgery. There was no difference in the outcome measures (ie, discharge, surgery, and death). There was a decline in nutritional parameters in both groups.

CONCLUSIONS

EN at a slow infusion is well tolerated by both NJ and NG routes in patients with SAP. Neither NJ nor NG feeding leads to recurrence or worsening of pain in SAP. Nutritional parameters remained unaffected because of inadequate calorie intake during the first week of feeding.

ESPEN Guidelines on Enteral Nutrition: Pancreas

The two major forms of inflammatory pancreatic diseases, acute and chronic pancreatitis, require different approaches in nutritional management, which are presented in the present guideline. This clinical practice guideline gives evidence-based recommendations for the use of ONS and TF in these patients. It was developed by an interdisciplinary expert group in accordance with officially accepted standards and is based on all relevant publications since 1985. The guideline was discussed and accepted in a consensus conference. In mild acute pancreatitis enteral nutrition (EN) has no positive impact on the course of disease and is only recommended in patients who cannot consume normal food after 5-7 days. In severe necrotising pancreatitis EN is indicated and should be supplemented by parenteral nutrition if needed. In the majority of patients continuous TF with peptide-based formulae is possible. The jejunal route is recommended if gastric feeding is not tolerated. In chronic pancreatitis more than 80% of patients can be treated adequately with normal food supplemented by pancreatic enzymes. 10-15% of all patients require nutritional supplements, and in approximately 5% tube feeding is indicated.

Reduced body protein in children with spastic quadriplegic cerebral palsy

BACKGROUND

No studies have directly measured body protein or validated skinfold-thickness anthropometry and dual-energy X-ray absorptiometry (DXA) to assess body protein in children with spastic quadriplegic cerebral palsy (SQCP).

OBJECTIVE

We aimed to measure and evaluate body protein and to determine whether skinfold-thickness anthropometry and DXA can predict body protein in children with SQCP.

DESIGN

This was a cross-sectional study of 59 children (22 girls, 37 boys) aged 3.9-19.5 y with SQCP. The children underwent measurements of anthropometric indexes, lean tissue mass by DXA (LTM(DXA)), and total body protein by neutron activation analysis (TBP(NAA)). In addition, TBP was estimated from both skinfold-thickness anthropometry (TBP(SKIN)) and DXA (TBP(DXA)). The agreement of TBP(SKIN) and TBP(DXA) was tested against TBP(NAA) by using Bland and Altman plot analysis.

RESULTS

Height and weight SD scores (x +/- SD: -3.1 +/- 1.6 and -4.8 +/- 5.3, respectively) were significantly lower than reference data in the children with SQCP (P < 0.001). TBP(NAA) for age and height was low in the children with SQCP (P < 0.001): 56.1 +/- 17.3% and 81.5 +/- 15.7%, respectively, of the values predicted from control data. TBP(SKIN) and TBP(DXA) were both highly correlated with TBP(NAA): r = 0.90, P < 0.001, and r = 0.91, P < 0.001, respectively. Despite these significant correlations, agreement analyses showed wide variation of up to 33.3% of the mean for both methods.

CONCLUSIONS

Body protein in children with SQCP is significantly reduced for age and height. Skinfold anthropometry and DXA show wide variation in estimation of body protein compared with NAA in this group of children.

The impact of parenteral nutrition on the body composition of patients with acute pancreatitis

BACKGROUND

Nutrition support by the enteral route is now the preferred modality in patients with severe acute pancreatitis. Parenteral nutrition is now required to supplement enteral nutrition when the latter is not able to provide the full nutritional requirement. We report the changes in body composition, plasma proteins, and resting energy expenditure (REE) during 14 days of parenteral nutrition (PN) in patients with acute pancreatitis.

METHODS

Total body protein (TBP), total body water (TBW), and total body fat (TBF) were measured by neutron activation analysis and tritium dilution before and after PN. Fat-free mass (FFM) was derived as the difference between body weight and TBF. REE was measured by indirect calorimetry. Protein index (PI) was the ratio of measured TBP to TBP, calculated from healthy volunteers.

RESULTS

Fifteen patients with acute pancreatitis (11 men, 4 women; median age 56, range 30-80 years) were studied. Thirteen patients had severe acute pancreatitis (Atlanta criteria), and 1 patient died. The gains in body weight (1.05 +/- 0.77 kg), TBW (0.49 +/- 0.87 kg), TBP (0.20 +/- 0.22 kg), FFM (0.73 +/- 0.92 kg), TBF (0.32 +/- 0.95 kg), and REE (146 +/- 90 kcal/d) after 14 days of PN were not significant. Plasma prealbumin increased by 46.5% (p = .020). When patients (n = 6) with intercurrent sepsis and recent surgery were excluded, there were significant increases in TBP (0.65 +/- 0.17 kg, p = .005) and PI (0.060 +/- 0.011, p = .0006).

CONCLUSIONS

Body composition is preserved in acute pancreatitis during 14 days of PN. In patients without sepsis or recent surgery, PN is able to significantly increase body protein stores.

Relationships between structural and functional measures of nutritional status in a normally nourished population

BACKGROUND AND AIMS

Both anthropometric and functional measurements have been used in nutritional assessment and monitoring. Hand dynamometry is a predictor of surgical outcome and peak expiratory flow rate has been used as an index of respiratory muscle function. This study aims to measure in normal subjects the relationship between anthropometric measurements, voluntary muscle strength by hand grip dynamometry and respiratory muscle function by peak expiratory flow rate.

METHODS

Ninety-eight subjects (46 male, 52 female) with a mean age of 45.9 years were studied. Hand grip strength was measured in the dominant and non-dominant hands with a portable strain-gauge dynamometer. Peak expiratory flow rate was measured using a mini-Wright peak flow meter. Three readings were taken, each 1 min apart, and the average recorded. Midarm muscle circumference (MAMC) was derived from triceps skin fold thickness and midarm circumference (MAC) using standard anthropometric techniques. Statistical relationships were measured with Pearson's coefficient of correlation.

RESULTS

In both sexes there was significant correlation between hand grip strength in the dominant and non-dominant hands and peak expiratory flow rate (P<0.001). In men, there was a positive correlation between MAMC, hand grip strength (P<0.001) and peak expiratory flow rate (P<0.001). In women muscle function correlated with height (P<0.001) but not MAMC (P>0.05).

CONCLUSIONS

In normal subjects bedside tests of skeletal and respiratory muscle function correlated with each other in both sexes, and with muscle mass in men but not in women.

Guidelines for nutritional support in intensive care unit patients: a critical analysis

PURPOSE OF REVIEW

Guidelines are supposed to be helpful in clinical practice. Guidelines are also supposed to rest upon the evidence that there is. In the field of clinical nutrition the problem is that many clinical trials are not conclusive because they are underpowered and sometimes have an inferior design.

RECENT FINDINGS

The publication of the Canadian guidelines one year ago initiated a lively debate. The Canadian guidelines used meta-analysis as a tool to review the literature. This resulted in both a sound evaluation of studies as well as some controversial recommendations. The Canadian guidelines are here put in a perspective in which the older type of guidelines are compared, and some of the points of recommendation are scrutinized.

SUMMARY

What all guidelines agree upon is the shortage of solid knowledge, the conviction that complications related to nutritional therapy in the intensive care unit are not acceptable, and that enteral nutrition is preferable if it can be given without risk. Beyond that, many controversies remain and the need for high quality prospective studies must be emphasized. In addition, such studies must address the clinically important questions that the guidelines try to answer.

Can bioelectrical impedance analysis identify malnutrition in preoperative nutrition assessment?

OBJECTIVE

Malnutrition is characterized by changes in cellular membrane integrity and alterations in fluid balance, both of which can be detected by bioelectrical impedance analysis (BIA). We investigated whether BIA-measured variables could detect malnutrition, as defined by the Subjective Global Assessment (SGA), in preoperative surgical patients.

METHODS

We prospectively evaluated 279 patients hospitalized for elective gastrointestinal surgery during the first 72 h after admission. BIA estimates were used to derive body cell mass, ratio of extracellular mass to body cell mass, and phase angle. Malnutrition diagnosed with these measures was compared with the SGA score. Receiver operating characteristic curves also were formulated to explore alternative cutoff points for one measure, phase angle.

RESULTS

A linear trend for means across SGA categories was found for all indicators used, except percentage of body cell mass. However, there was only fair overall agreement between SGA and BIA estimates. The receiver operating characteristic curves for phase angle suggested that the test was too sensitive or too specific. No alternative cutoff points resulted in suitable tests that could provide an alternative to SGA.

CONCLUSIONS

Although not in close agreement with SGA, the results suggested that there are some alterations in tissue electrical properties with malnutrition that can be detected by BIA. New cutoff points may be needed for application of BIA as a complementary method in the nutrition assessment of surgical patients.

Development of bioelectrical impedance analysis prediction equations for body composition with the use of a multicomponent model for use in epidemiologic surveys

BACKGROUND

Previous studies to develop and validate bioelectrical impedance analysis (BIA) equations to predict body composition were limited by small sample sizes, sex specificity, and reliance on reference methods that use a 2-component model.

OBJECTIVE

This study was designed to develop sex-specific BIA equations to predict total body water (TBW) and fat-free mass (FFM) with the use of a multicomponent model for children and adults.

DESIGN

Data from 5 centers were pooled to create a sample of 1474 whites and 355 blacks aged 12-94 y. TBW was measured by dilution, and FFM was estimated with a multicomponent model based on densitometry, isotope dilution, and dual-energy X-ray absorptiometry.

RESULTS

The final race-combined TBW prediction equations included stature(2)/resistance and body weight (R(2) = 0.84 and 0.79 and root mean square errors of 3.8 and 2.6 L for males and females, respectively; CV: 8%) and tended to underpredict TBW in black males (2.0 L) and females (1.4 L) and to overpredict TBW in white males (0.5 L) and females (0.3 L). The race-combined FFM prediction equations contained the same independent variables (R(2) = 0.90 and 0.83 and root mean square errors of 3.9 and 2.9 kg for males and females, respectively; CV: approximately 6%) and tended to underpredict FFM in black males (2.1 kg) and females (1.6 kg) and to overpredict FFM in white males (0.4 kg) and females (0.3 kg).

CONCLUSION

These equations have excellent precision and are recommended for use in epidemiologic studies to describe normal levels of body composition.

[Subjective nutrition assessment: Part 1 - A review of its validity after two decades of use]

BACKGROUND

The subjective global assessment is a clinical method for nutritional assessment that considers not only body composition alterations but also changes in physiological function. The method is simple, inexpensive and non-invasive, and it can be performed at bedside, and its use was described for the first time almost two decades ago.

AIM

To review the validity studies of subjective global assessment described in literature in the last two decades of its use.

METHODS

It was performed a systematic review in MEDLINE, using "subjective global assessment" as search term and the most relevant papers were selected.

RESULTS

Being a subjective method, its precision depends on the observer's experience. Nevertheless, the method showed a good diagnostic precision when performed by trained observers. Subjective global assessment was validated by convergent validity, when this method was compared to other objective nutritional assessment methods, and by predictive validity, showing that subjective global assessment could identify patients who were at high risk for developing postoperative complications.

CONCLUSIONS

Subjective global assessment has been a good option in nutritional assessment in surgical patients and some modifications have been suggested to adjust the method to other clinical situations. The observer experience is of extreme importance, since the precision of the method depends on it.