title: Evaluation of C-terminal Agrin Fragment as a marker of muscle wasting in patients after acute stroke during early rehabilitation.
abstract: C-terminal Agrin Fragment (CAF) has been proposed as a novel biomarker for sarcopenia originating from the degeneration of the neuromuscular junctions. In patients with stroke muscle wasting is a common observation that predicts functional outcome. We aimed to evaluate agrin sub-fragment CAF22 as a marker of decreased muscle mass and physical performance in the early phase after acute stroke.
  
  
  
  Patients with acute ischaemic or haemorrhagic stroke (n = 123, mean age 70 ± 11 y, body mass index BMI 27.0 ± 4.9 kg/m(2)) admitted to inpatient rehabilitation were studied in comparison to 26 healthy controls of similar age and BMI. Functional assessments were performed at begin (23 ± 17 days post stroke) and at the end of the structured rehabilitation programme (49 ± 18 days post stroke) that included physical assessment, maximum hand grip strength, Rivermead motor assessment, and Barthel index. Body composition was assessed by bioelectrical impedance analysis (BIA). Serum levels of CAF22 were measured by ELISA.
  
  
  
  CAF22 levels were elevated in stroke patients at admission (134.3 ± 52.3 pM) and showed incomplete recovery until discharge (118.2 ± 42.7 pM) compared to healthy controls (95.7 ± 31.8 pM, p < 0.001). Simple regression analyses revealed an association between CAF22 levels and parameters of physical performance, hand grip strength, and phase angle, a BIA derived measure of the muscle cellular integrity. Improvement of the handgrip strength of the paretic arm during rehabilitation was independently related to the recovery of CAF22 serum levels only in those patients who showed increased lean mass during the rehabilitation.
  
  
  
  CAF22 serum profiles showed a dynamic elevation and recovery in the subacute phase after acute stroke. Further studies are needed to explore the potential of CAF22 as a serum marker to monitor the muscle status in patients after stroke.
authors.affiliation: Center for Stroke Research CSB Charite Universitätsmedizin Berlin Germany; German Centre for Cardiovascular Research (DZHK), partner site Berlin Germany.
authors.forename: Nadja
authors.initials: N
authors.lastname: Scherbakov
authors.affiliation: Center for Stroke Research CSB Charite Universitätsmedizin Berlin Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Knops
authors.affiliation: Innovative Clinical Trials, Department of Cardiology and Pneumology University Medicine Göttingen Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Ebner
authors.affiliation: Innovative Clinical Trials, Department of Cardiology and Pneumology University Medicine Göttingen Germany; 1st Department of Internal Medicine Comenius University Bratislava Slovak Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Valentova
authors.affiliation: Innovative Clinical Trials, Department of Cardiology and Pneumology University Medicine Göttingen Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Sandek
authors.affiliation: Center for Stroke Research CSB Charite Universitätsmedizin Berlin Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Grittner
authors.affiliation: Neurotune AG Wagistrasse 27a Schlieren Switzerland.
authors.forename: Pius
authors.initials: P
authors.lastname: Dahinden
authors.affiliation: Neurotune AG Wagistrasse 27a Schlieren Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hettwer
authors.affiliation: Department of Intensive Care Medicine Inselspital, University Hospital of Bern Switzerland.
authors.forename: Jörg C
authors.initials: JC
authors.lastname: Schefold
authors.affiliation: Innovative Clinical Trials, Department of Cardiology and Pneumology University Medicine Göttingen Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: von Haehling
authors.affiliation: Innovative Clinical Trials, Department of Cardiology and Pneumology University Medicine Göttingen Germany.
authors.forename: Stefan D
authors.initials: SD
authors.lastname: Anker
authors.affiliation: Department of Neurology Brandenburgklinik Bernau Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Joebges
authors.affiliation: Center for Stroke Research CSB Charite Universitätsmedizin Berlin Germany; German Centre for Cardiovascular Research (DZHK), partner site Berlin Germany; Department of Cardiology Charite Universitätsmedizin Berlin Germany.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Doehner
keywords: C‐terminal Agrin Fragment; Muscle wasting; Physical performance; Post‐stroke rehabilitation; Skeletal muscle mass; Stroke