title: Assessment of physical fatigability and fatigue perception in myasthenia gravis.
abstract: Fatigue includes both performance fatigability and fatigue perception.
  
  
  
  In 32 stable patients with generalized myasthenia gravis (MG) and 17 controls, time-dependent physical performance was assessed by the arm movement test (AMT) and 6-minute walk test (6MWT). MG patients presented with low quantitative MG scores (mean 0.5, SD 0.5) and without pathologic decrement. Fatigability was based on calculation of linear trend (LT) reflecting dynamic performance within subsequent constant time intervals. Perception of physical fatigue was analyzed using fatigue questionnaires.
  
  
  
  MG patients showed a negative LT in both AMT and 6MWT, significantly differing from stable performance in controls. LT inversely correlated with elevation of acetylcholine receptor antibodies (r = -0.59, P < 0.005) but not with quantitative MG score and fatigue perception.
  
  
  
  LT allows quantification of fatigability as an objective measurement of decline in individual performance, even in patients without obvious neuromuscular deficits in routine testing. The missing correlation of experienced fatigue supports the multidimensional fatigue model. Muscle Nerve 55: 657-663, 2017.
authors.affiliation: Department of Neurology, Martin Luther University Halle, Ernst-Grube-Strasse 40, 06120, Halle, Germany.
authors.forename: Berit
authors.initials: B
authors.lastname: Jordan
authors.affiliation: Department of Neurology, Martin Luther University Halle, Ernst-Grube-Strasse 40, 06120, Halle, Germany.
authors.forename: Theresa
authors.initials: T
authors.lastname: Mehl
authors.affiliation: Institute of Psychology, Martin Luther University Halle, Halle/Saale, Germany.
authors.forename: Tabea L K
authors.initials: TLK
authors.lastname: Schweden
authors.affiliation: Institute of Psychology, Martin Luther University Halle, Halle/Saale, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Menge
authors.affiliation: Department of Neurology, Martin Luther University Halle, Ernst-Grube-Strasse 40, 06120, Halle, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Zierz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood; D005080:Exercise Test; D005221:Fatigue / Q000276:immunology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018763:Muscle Fatigue / Q000502:physiology*; D009157:Myasthenia Gravis / Q000276:immunology / Q000503:physiopathology*; D010465:Perception / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D011950:Receptors, Cholinergic / Q000276:immunology; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D011950:Receptors, Cholinergic
keywords: antibody; fatigability; fatigue perception; linear trend; myasthenia gravis; pathologic decrement; physical fatigue; weakness