title: Role of the cardio-pulmonary exercise test and six-minute walking test in the evaluation of exercise performance in patients with late-onset Pompe disease.
abstract: In patients with late-onset Pompe disease, we explored the role of the Cardiopulmonary Exercise Test (CPET) and the Six-Minute Walking Test (6MWT) in the assessment of exercise capacity and in the evaluation of the effects of enzyme replacement therapy (ERT). Eight patients affected by late-onset Pompe disease, followed up at the Centre for Neuromuscular Diseases and treated with ERT, underwent a baseline evaluation with a spirometry, a CPET and a 6MWT. Four of them were restudied after 36 months of treatment. Three patients showed a reduction in exercise capacity as evaluated by peak oxygen uptake (VO2) measured at the CPET and Distance Walked (DW) measured at the 6MWT (median % predicted: 67.1 [range 54.3-99.6] and 67.3 [56.6-82.6], respectively). Cardiac and respiratory limitations revealed by the CPET were correlated to peak VO2, but not to the DW. Nevertheless, percent of predicted values of peak VO2 and DW were strongly correlated (rho = 0.85, p = 0.006), and close to identity. In the longitudinal evaluation forced vital capacity decreased, while peak VO2 and DW showed a trend to a parallel improvement. We concluded that although only the CPET revealed causes of exercise limitation, which partially differed among patients, CPET and 6MWT showed a similar overall degree of exercise impairment. That held true in the longitudinal assessment during ERT, where both tests demonstrated similar small improvements, occurring despite deterioration in forced vital capacity.
authors.affiliation: Italian National Research Council, Institute of Biomedicine and Molecular Immunology, Palermo, Italy; Department of Pneumology, Villa Sofia - Cervello Hospital, Palermo, Italy. Electronic address: grazia.crescimanno@ibim.cnr.it.
authors.forename: G
authors.initials: G
authors.lastname: Crescimanno
authors.affiliation: Department of Pneumology, Villa Sofia - Cervello Hospital, Palermo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Modica
authors.affiliation: Department of Cardiology, Villa Sofia - Cervello Hospital, Palermo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Lo Mauro
authors.affiliation: Department of Neurosciences, Reference Centre for Rare Neuromuscular Disorders, University of Messina, Italy.
authors.forename: O
authors.initials: O
authors.lastname: Musumeci
authors.affiliation: Department of Neurosciences, Reference Centre for Rare Neuromuscular Disorders, University of Messina, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Toscano
authors.affiliation: Italian National Research Council, Institute of Biomedicine and Molecular Immunology, Palermo, Italy.
authors.forename: O
authors.initials: O
authors.lastname: Marrone
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006009:Glycogen Storage Disease Type II / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D013147:Spirometry; D016896:Treatment Outcome; D014797:Vital Capacity; D016138:Walking / Q000502:physiology
keywords: 6MWT; Cardiopulmonary exercise test; Enzyme replacement therapy; Exercise capacity; Late onset Pompe disease