title: Cross-sectional retrospective study of muscle function in patients with glycogen storage disease type III.
abstract: Glycogen storage disease type III is an inherited metabolic disorder characterized by liver and muscle impairment. This study aimed to identify promising muscle function measures for future studies on natural disease progression and therapeutic trials. The age-effect on the manual muscle testing (MMT), the hand-held dynamometry (HHD), the motor function measure (MFM) and the Purdue pegboard test was evaluated by regression analysis in a cross-sectional retrospective single site study. In patients aged between 13 and 56 years old, the Purdue pegboard test and dynamometry of key pinch and knee extension strength were age-sensitive with annual losses of 1.49, 1.10 and 0.70% of the predicted values (%pred), respectively. The MFM score and handgrip strength were also age-sensitive but only in patients older than 29 and 37 years old with annual losses of 1.42 and 1.84%pred, respectively. Muscle strength assessed by MMT and elbow extension measured by HHD demonstrated an annual loss of less than 0.50%pred and are thus unlikely to be promising outcome measures for future clinical trials. In conclusion, our results identified age-sensitive outcomes from retrospective data and may serve for future longitudinal studies in which an estimation of the minimal number of subjects is provided.
authors.affiliation: Institut de Myologie, APHP - GH Pitié-Salpêtrière, Bd de l'Hôpital, Paris 75651 Cedex 13, France. Electronic address: v.decostre@institut-myologie.org.
authors.forename: Valérie
authors.initials: V
authors.lastname: Decostre
authors.affiliation: Paris-Est Neuromuscular Center , APHP - GH Pitié-Salpêtrière, Paris, France; INSERM UMRS 974, Paris, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Laforêt
authors.affiliation: Centre de référence des maladies neuromusculaires Nantes/Angers, Service de Neurologie, CHU Angers, Angers, France.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Nadaj-Pakleza
authors.affiliation: INSERM U1138-team22, Centre de Recherche des Cordeliers, Paris Descartes and UPMC University, Paris, France.
authors.forename: Marie
authors.initials: M
authors.lastname: De Antonio
authors.affiliation: INSERM U1138-team22, Centre de Recherche des Cordeliers, Paris Descartes and UPMC University, Paris, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Leveugle
authors.affiliation: Institut de Myologie, APHP - GH Pitié-Salpêtrière, Bd de l'Hôpital, Paris 75651 Cedex 13, France.
authors.forename: Gwenn
authors.initials: G
authors.lastname: Ollivier
authors.affiliation: Institut de Myologie, APHP - GH Pitié-Salpêtrière, Bd de l'Hôpital, Paris 75651 Cedex 13, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Canal
authors.affiliation: Paris-Est Neuromuscular Center , APHP - GH Pitié-Salpêtrière, Paris, France.
authors.forename: Kahina
authors.initials: K
authors.lastname: Kachetel
authors.affiliation: Laboratoire de Génétique moléculaire, APHP - GH Antoine Béclère, Clamart, France.
authors.forename: François
authors.initials: F
authors.lastname: Petit
authors.affiliation: Paris-Est Neuromuscular Center , APHP - GH Pitié-Salpêtrière, Paris, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Eymard
authors.affiliation: Paris-Est Neuromuscular Center , APHP - GH Pitié-Salpêtrière, Paris, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Behin
authors.affiliation: Institut de Myologie, APHP - GH Pitié-Salpêtrière, Bd de l'Hôpital, Paris 75651 Cedex 13, France; Département de Cardiologie, APHP, Hôpital Cochin, Paris, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Wahbi
authors.affiliation: APHP, Hôpital Antoine Béclère, Centre de Référence Maladies Héréditaires du Métabolisme Hépatique, Hôpitaux Universitaires Paris Sud, Clamart, France; Université Paris Sud, Orsay, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Labrune
authors.affiliation: Institut de Myologie, APHP - GH Pitié-Salpêtrière, Bd de l'Hôpital, Paris 75651 Cedex 13, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Hogrel
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D001132:Arm / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D006010:Glycogen Storage Disease Type III / Q000235:genetics / Q000503:physiopathology*; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D053581:Muscle Strength Dynamometer; D018908:Muscle Weakness / Q000209:etiology / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000503:physiopathology*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Debranching enzyme deficiency; Glycogen storage disease type III; Metabolic myopathy; Outcome measures