title: Systemic inflammation, body composition, and physical performance in old community-dwellers.
abstract: BACKGROUND
  Chronic inflammation, changes in body composition, and declining physical function are hallmarks of the ageing process. The aim of the present study was to provide a preliminary characterisation of the relationship among these age-related phenomena via multivariate modelling.
  
  
  METHODS
  Thirty-five old adults (OAs) and 17 young adults (YAs) were enrolled. The volume of skeletal muscle, subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT) of the thigh was quantified by three-dimensional magnetic resonance imaging. Muscle strength was measured by knee extension strength testing. In OAs, physical performance was further assessed via the Short Physical Performance Battery (SPPB). Multi-block partial least squares-discriminant analysis (PLS-DA) was employed to explore the relationship among inflammatory profiles and functional and imaging parameters. Double cross-validation procedures were used to validate the predictive ability of the PLS-DA model.
  
  
  RESULTS
  The optimal complexity of the PLS-DA model was found to be two latent variables. The proportion of correct classification was 92.3% in calibration (94.1% in YAs and 91.4% in OAs), 84.6% in internal validation (95.3% in YAs and 78.5% in OAs), and 82.6% in external validation (94% in YAs and 76.9% in OAs). Relative to YAs, OAs were characterised by smaller muscle volume, greater IMAT volume, lower muscle strength, and higher levels of myeloperoxidase, P-selectin, soluble intercellular adhesion molecule 1, and vascular cell adhesion molecule 1. Compared with OAs with SPPB >8, those scoring ≤8 were characterised by smaller muscle volume, greater SAT volume, lower muscle strength, and higher levels of interleukin 1 beta, 6, 10, 12, 13, tumour necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor.
  
  
  CONCLUSIONS
  Multi-block PLS-DA identified distinct patterns of relationships among circulating cytokines and functional and imaging parameters in persons of different ages and varying levels of physical performance. The longitudinal implementation of such an innovative strategy could allow for the tracking of health status over time, the early detection of deviations in health trajectories, and the monitoring of response to treatments.
authors.affiliation: Department of Geriatrics, Neurosciences, and Orthopaedics, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Calvani
authors.affiliation: Department of Chemistry, 'Sapienza' University of Rome, Rome, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Marini
authors.affiliation: Gérontopôle, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.|Institut National de la Santé et de la Recherche Médicale (UMR1027), Université de Toulouse III Paul Sabatier, Toulouse, France.
authors.forename: Matteo
authors.initials: M
authors.lastname: Cesari
authors.affiliation: Department of Aging and Geriatrics, University of Florida, Gainesville, FL, USA.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Buford
authors.affiliation: Department of Aging and Geriatrics, University of Florida, Gainesville, FL, USA.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Manini
authors.affiliation: Department of Aging and Geriatrics, University of Florida, Gainesville, FL, USA.
authors.forename: Marco
authors.initials: M
authors.lastname: Pahor
authors.affiliation: Department of Aging and Geriatrics, University of Florida, Gainesville, FL, USA.
authors.forename: Christiaan
authors.initials: C
authors.lastname: Leeuwenburgh
authors.affiliation: Department of Geriatrics, Neurosciences, and Orthopaedics, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bernabei
authors.affiliation: Department of Geriatrics, Neurosciences, and Orthopaedics, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Landi
authors.affiliation: Department of Geriatrics, Neurosciences, and Orthopaedics, Catholic University of the Sacred Heart, Rome, Italy.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Marzetti
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000502:physiology*; D001823:Body Composition; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D057187:Independent Living; D007249:Inflammation / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology; D016018:Least-Squares Analysis; D008279:Magnetic Resonance Imaging; D008297:Male; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000502:physiology; D013848:Thigh / Q000000981:diagnostic imaging; D055815:Young Adult
chemical_list: D016207:Cytokines
keywords: Ageing; Cytokines; Inflammaging; Multi-block partial least squares - discriminant analysis; Muscle strength; Short Physical Performance Battery (SPPB)