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

This is the peer reviewed version of the following article: S, Smith & A. M. Madden (2016) ‘Body Composition and functional assessment of nutritional status in adults: a narrative review of imaging, impedance, strength and functional techniques’, Journal of Human Nutrition and Dietetics, 29 (6): 714-732, which has been published in final form at https://dx.doi.org/10.1111/jhn.12372. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.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.Peer reviewe

Assessment of body composition in health and disease using bioelectrical impedance analysis (bia) and dual energy x-ray absorptiometry (dxa): A critical overview

The measurement of body composition (BC) represents a valuable tool to assess nutritional status in health and disease. The most used methods to evaluate BC in the clinical practice are based on bicompartment models and measure, directly or indirectly, fat mass (FM) and fat-free mass (FFM). Bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) (nowadays considered as the reference technique in clinical practice) are extensively used in epidemiological (mainly BIA) and clinical (mainly DXA) settings to evaluate BC. DXA is primarily used for the measurements of bone mineral content (BMC) and density to assess bone health and diagnose osteoporosis in defined anatomical regions (femur and spine). However, total body DXA scans are used to derive a three-compartment BC model, including BMC, FM, and FFM. Both these methods feature some limitations: the accuracy of BIA measurements is reduced when specific predictive equations and standardized measurement protocols are not utilized whereas the limitations of DXA are the safety of repeated measurements (no more than two body scans per year are currently advised), cost, and technical expertise. This review aims to provide useful insights mostly into the use of BC methods in prevention and clinical practice (ambulatory or bedridden patients). We believe that it will stimulate a discussion on the topic and reinvigorate the crucial role of BC evaluation in diagnostic and clinical investigation protocols

Assessment of Body Composition in Health and Disease Using Bioelectrical Impedance Analysis (BIA) and Dual Energy X-Ray Absorptiometry (DXA): A Critical Overview

The measurement of body composition (BC) represents a valuable tool to assess nutritional status in health and disease. The most used methods to evaluate BC in the clinical practice are based on bicompartment models and measure, directly or indirectly, fat mass (FM) and fat-free mass (FFM). Bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) (nowadays considered as the reference technique in clinical practice) are extensively used in epidemiological (mainly BIA) and clinical (mainly DXA) settings to evaluate BC. DXA is primarily used for the measurements of bone mineral content (BMC) and density to assess bone health and diagnose osteoporosis in defined anatomical regions (femur and spine). However, total body DXA scans are used to derive a three-compartment BC model, including BMC, FM, and FFM. Both these methods feature some limitations: the accuracy of BIA measurements is reduced when specific predictive equations and standardized measurement protocols are not utilized whereas the limitations of DXA are the safety of repeated measurements (no more than two body scans per year are currently advised), cost, and technical expertise. This review aims to provide useful insights mostly into the use of BC methods in prevention and clinical practice (ambulatory or bedridden patients). We believe that it will stimulate a discussion on the topic and reinvigorate the crucial role of BC evaluation in diagnostic and clinical investigation protocols

Body composition in clinical practice

Nutritional status is the results of nutrients intake, absorption and utilization, able to influence physiological and pathological conditions. Nutritional status can be measured for individuals with different techniques, such as CT Body Composition, quantitative Magnetic Resonance Imaging, Ultrasound, Dual-Energy X-Ray Absorptiometry and Bioimpendance. Because obesity is becoming a worldwide epidemic, there is an increasing interest in the study of body composition to monitor conditions and delay in development of obesity-related diseases. The emergence of these evidence demonstrates the need of standard assessment of nutritional status based on body weight changes, playing an important role in several clinical setting, such as in quantitative measurement of tissues and their fluctuations in body composition, in survival rate, in pathologic condition and illnesses. Since body mass index has been shown to be an imprecise measurement of fat-free and fat mass, body cell mass and fluids, providing no information if weight changes, consequently there is the need to find a better way to evaluate body composition, in order to assess fat-free and fat mass with weight gain and loss, and during ageing. Monitoring body composition can be very useful for nutritional and medical interventional. This review is focused on the use of Body Composition in Clinical Practice

Comparison of various methods of measuring body composition to underwater weighing in adult men and women

Nine different methods of measuring body composition were compared to underwater weighing in average Caucasian adult men and women, to determine which method correlated highest with UWW. Fifty participants were tested on underwater weighing, air displacement plethysmoghraphy, Dual Energy X-Ray Absorptiometry, bioelectrical impedance analysis, ultrasound, near infrared reactance, and skinfolds---sum of 7, 4, and 3 sites; All correlations for both genders were high at the .05 level. For men the highest correlation was between UWW and the sum of 4 skinfolds at .971 and the lowest between UWW and BIA of .748. For women the highest correlation was between UWW and the sum of 4 skinfolds at .962 and the lowest between UWW and ultrasound of .778; This study concluded that accuracy of different techniques would depend on population specific limitations. For the present sample accuracy of methods differed slightly between genders, but did not differ significantly from UWW

Comparison between Dual-X-ray Absorptiometry and Bioelectrical Impedance Analyses in dietary practice

Body composition assessment is an essential part of assessing overall health, training progress, nutritional status, and monitoring the level of body fat and lean tissue content. This article is a review made to compare body composition analysis methods with the help of BIA and DXA as a dieticians’ working tool. The practical advantages of the bioimpedance method enable the wide application of this method in dietary practice. BIA can be a safe and helpful method for monitoring patient progression in terms of changes in body composition. Although DXA is currently the gold standard for measuring body composition in clinical trials, the use of this method is associated with numerous limitations resulting from the high cost of the technique, limited availability of this type of equipment and time consumption

Measuring Muscle Mass and Strength in Obesity:A Review of Various Methods

Lower muscle mass in populations with obesity is associated obesity-related diseases like hypertension and type 2 diabetes mellitus. Bariatric surgery leads to sustained weight loss. During the weight reduction, loss of muscle should be minimized. Thus reliable quantification of muscle mass is much needed and therefore the also the need for validated methods. Imaging methods, magnetic resonance imaging and computed tomography scan, have been the gold standard for many years. However, these methods are costly and have limitations such as the maximum weight. Dual-energy X-ray absorptiometry is currently the most used alternative. Other, less expensive methods are very limited in their validation in populations with morbid obesity. This narrative review summarizes the current knowledge regarding measuring muscle mass and strength in obesity