title: Phase angle as bioelectrical marker to identify elderly patients at risk of sarcopenia.
abstract: Several markers have been associated with sarcopenia in the elderly, including bioelectrical indices. Phase angle (PhA) is an impedance parameter and it has been suggested as an indicator of cellular death. Thus, the relationship between PhA and muscle mass and strength was investigated in 207 consecutively elderly participants (mean age 76.2±6.7years) admitted for multidimensional geriatric evaluation. Muscle strength by grip strength using a hand-held dynamometer and muscle mass was measured by bioimpedentiometer. PhA was calculated directly with its arctangent (resistance/reactance×180°/π). Linear relationship among muscular mass and strength and with clinical and biochemical parameters, including PhA at uni- and multivariate analysis were performed. Linear regression analysis demonstrated that lower level of PhA is associated with reduction in grip strength (y=3.16+0.08x; r=0.49; p<0.001), and even more, with muscle mass (y=3.04+0.25x; r=0.60; p<0001). Multivariate analysis confirms these relationships (grip strength β=0.245, p=0.031; muscular mass β=0.623, p<0.01). Thus, PhA is inversely related to muscle mass and strength in elderly subjects and it may be considered a good bioelectrical marker to identify elderly patients at risk of sarcopenia.
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Basile
authors.affiliation: Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy; IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: David
authors.initials: D
authors.lastname: Della-Morte
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy; Division of Geriatrics, AON SS. Antonio e Biagio e Cesare Arrigo, Alessandria, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Cacciatore
authors.affiliation: IRCCS Salvatore Maugeri Foundation, Scientific Institute of Campoli/Telese, Benevento, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Gargiulo
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy; IRCCS Salvatore Maugeri Foundation, Scientific Institute of Veruno, Novara, Italy.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Galizia
authors.affiliation: Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Roselli
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Curcio
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Bonaduce
authors.affiliation: Department of Translational Medical Sciences, University of Naples "Federico II", Naples, Italy. Electronic address: p.abete@unina.it.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Abete
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D017097:Electric Impedance; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D018737:Hand Strength; D006801:Humans; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000473:pathology* / Q000503:physiopathology; D009929:Organ Size; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D055948:Sarcopenia / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology
keywords: Angle phase; Bioelectrical impedance; Elderly; Sarcopenia