Can Dietitians Reliably Measure Muscle Mass with Ultrasound Compared to ‘expert’ Clinicians and What Sort of Training is Required? A Narrative Review.

OBJECTIVES:Sarcopenia and malnutrition have detrimental health related outcomes not limited to falls, weakness, fractures, increased hospital length of stay, increased risk of infections, morbidity and mortality. Ultrasound is an establishing imaging modality that can be utilized at point-of care to measure muscle mass and quality. It is cheaper, less invasive, and more accessible than other gold-standard measurements of muscle mass. It is proposed that dietitians can utilize this measurement in clinical practice to support both diagnosis and monitoring of malnutrition and sarcopenia, however current evidence has not been synthesized. METHODS:The search was completed in May 2024. MEDLINE, EMBASE, PubMed and Cochrane databases were searched. Search terms and search procedures were transposed across different databases based on known Booleen operators. Due to paucity of evidence in the area, a broad search strategy was employed. Simply the combination of synonyms of ultrasound and dietitian within any field was used to ensure any kind of ultrasound measured by a dietitian was captured. RESULTS:The initial search identified 946 titles for review from which 228 duplicates were removed, leaving 718 for screening. After screening, 55 papers remained for full-text review. Ten papers were included for appraisal. All peer-reviewed papers were observational, 441 participants in total were included (both healthy participants and patient cohorts). Study quality was low, with study design, documentation of training, timing of measurement and blinding poorly defined. The reference standard (if any) was inconsistent. All studies were basic research, none were translated into clinical practice. Quad muscle thickness was the most common measurement. Reliability of dietitians was reported in most, with intra-rater ICC ranges from 0.63 to 0.95 between dietitians and 'experts' (intensivists, trained clinicians or sonographers). Training undertaken was reported in half the papers reviewed but details were limited. CONCLUSION:Emerging evidence suggests dietitians have potential to develop skills in measuring muscles with ultrasound. Overall, there remains a paucity of publications in the area, particularly when considering dietitian training and reliability in various ultrasound measurements. There should be progress in Further studies with regard to verifying necessary training for dietitians to ensure accurate readings as an advanced scope of practice for dietitians.