title: The role of DXA in sarcopenia.
abstract: Sarcopenia is a condition characterized by progressive and generalized reduction in skeletal muscle mass and muscle strength, associated with an increased risk of adverse outcomes (disability, hospitalization, death). The growing attention in the last years, aiming to establish a consensus definition and treatment, reflects the interest of the scientific community toward this complex condition, which has many implications in clinical practice and public health. Dual-energy X-ray absorptiometry (DXA) is the gold-standard technique in the analysis of body composition at molecular level, providing assessment and quantification of fat mass, lean mass and bone mineral content, both in a single body region of interest and at whole-body level. In particular, through the assessment of non-bone lean mass parameters, such as appendicular lean mass adjusted for BMI or height (ALM/BMI and ALM/ht2, respectively), it is possible to discriminate subjects with "physiological" loss of muscle mass from those with "pathological" impoverishment of this compartment, referring to specific cutoff values validated in the literature, but keeping in mind the lack of standardization of DXA measures. In addition, it is useful in treatment planning, estimating resting energy expenditure, and in follow-up, because it allows quantifying with high reproducibility the modifications in BC, distinguishing when the change is biological (deterioration due to a progression of the disease or improvement due to treatment). Due to DXA favorability in terms of accuracy, simplicity, availability, low cost and low radiation exposure, its role in sarcopenia diagnosis is becoming increasingly important, emerging as reference assessment technique in muscle mass evaluation.
authors.affiliation: Department of Radiology, University of Foggia, Viale Luigi Pinto 1, 71100, Foggia, Italy. giuseppe.guglielmi@unifg.it.|Department of Radiology, Scientific Institute "Casa Sollievo della Sofferenza" Hospital, Viale Cappuccini 1, 71013, San Giovanni Rotondo, Foggia, Italy. giuseppe.guglielmi@unifg.it.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Guglielmi
authors.affiliation: Department of Specialized, Diagnostic, and Experimental Medicine, Sant'Orsola - Malpighi Hospital, University of Bologna, Via G. Massarenti 9, 40138, Bologna, Italy.|Diagnostic and Interventional Radiology, The "Rizzoli" Orthopaedic Institute, Via G. C. Pupilli 1, 40136, Bologna, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Ponti
authors.affiliation: Department of Specialized, Diagnostic, and Experimental Medicine, Sant'Orsola - Malpighi Hospital, University of Bologna, Via G. Massarenti 9, 40138, Bologna, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Agostini
authors.affiliation: Department of Specialized, Diagnostic, and Experimental Medicine, Sant'Orsola - Malpighi Hospital, University of Bologna, Via G. Massarenti 9, 40138, Bologna, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Amadori
authors.affiliation: Department of Specialized, Diagnostic, and Experimental Medicine, Sant'Orsola - Malpighi Hospital, University of Bologna, Via G. Massarenti 9, 40138, Bologna, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Battista
authors.affiliation: Diagnostic and Interventional Radiology, The "Rizzoli" Orthopaedic Institute, Via G. C. Pupilli 1, 40136, Bologna, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bazzocchi
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000368:Aged; D000375:Aging / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D015519:Bone Density / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000503:physiopathology; D015203:Reproducibility of Results; D055948:Sarcopenia / Q000175:diagnosis / Q000503:physiopathology
keywords: Absorptiometry; Aging; Body composition; Diagnosis; Muscle; Photon; Sarcopenia