The Correlation Between Static Fatigue Testing and the Quantitative Myasthenia Gravis Score and Activities of Daily Living Profile

Fatigue is a common symptom in myasthenia gravis (MG), but both objective and subjective measures of fatigue are poorly studied in the disease.  We conducted a pilot study of static fatigue testing (SFT) in a group of MG patients, using an isometric quantified muscle analysis computer system.  Results from sustained isometric contraction of 5 muscle groups in 77 patients were correlated to the Quantitative MG Score (QMG) and the Activities of Daily Living Profile (MG-ADL), two commonly used outcome measures.  Pearson correlation coefficients for the SFT were highest (0.33) for hand grip for both the QMG and MG-ADL.  Correlations were quite poor for the proximal muscle groups and ankle dorsiflexion.  More work is needed to develop objective and subjective measures of fatigue in MG.  &nbsp