Six minute walk test in type III spinal muscular atrophy: A 12 month longitudinal study E. Mazzone a , F. Bianco a , M. Main b , M. van den Hauwe c , M. Ash b , R. de Vries d , J. Fagoaga Mata e , S. Stein f , R. De Sanctis a , A. D’Amico g,h , C. Palermo a , L. Fanelli a , M.C. Scoto b , A. Mayhew i , M. Eagle i , M. Vigo e , A. Febrer e , R. Korinthenberg f , M. de Visser d , K. Bushby i , F. Muntoni b , N. Goemans c , M.P. Sormani j , E. Bertini g,h , M. Pane a , E. Mercuri a,⇑ a Department of Paediatric Neurology, Catholic University, Rome, Italy b Dubowitz Neuromuscular Centre, Institute of Child Health, University College, London, UK c Child Neurology, University Hospitals Leuven, Leuven, Belgium d Department of Neurology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands e Service of Physical Medicine and Rehabilitation, University Hospital Sant Joan de Deu, Barcelona, Spain f Department of Neuropediatrics and Muscular Disorders, University Medical Centre, Freiburg, Germany g Child and Adolescence Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesu ` Hospital, Rome, Italy h Department of Laboratory Medicine, Unit of Molecular Medicine, Bambino Gesu ` Hospital, Rome, Italy i Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK j Biostatistics Unit, Department of Health Sciences, University of Genoa, Italy Received 18 March 2013; received in revised form 28 May 2013; accepted 6 June 2013 Abstract The aim of our longitudinal multicentric study was to establish the changes on the 6 min walk test (6MWT) in ambulant SMA type III children and adults over a 12 month period. Thirty-eight ambulant type III patients performed the 6MWT at baseline and 12 months after baseline. The distance covered in 6 min ranged between 75 and 510 m (mean 294.91, SD 127) at baseline and between 50 and 611 m (mean 293.41 m, SD 141) at 12 months. The mean change in distance between baseline and 12 months was À1.46 (SD 50.1; range: À183 to 131.8 m). The changes were not correlated with age or baseline values (p > .05) even though younger patients reaching puberty, had a relatively higher risk of showing deterioration of more than 30 m compared to older patients. Our findings provide the first longitudinal data using the 6MWT in ambulant SMA patients. Ó 2013 Elsevier B.V. All rights reserved. Keywords: Spinal muscular atrophy; Outcome measures; 6MWT 1. Introduction Spinal muscular atrophy (SMA) is a neuromuscular disease characterized by degeneration of alpha motor neurons in the spinal cord. In the last years the prospective of clinical trials has highlighted the need for identifying methods of assessments that could be used as outcome measures and to collect natural history data [1–3]. A recent study has suggested that 6MWT can be reliably used in ambulant SMA patients, is sensitive to fatigue- related changes and could be a suitable outcome measure in clinical trials [4]. 0960-8966/$ - see front matter Ó 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.nmd.2013.06.001 ⇑ Corresponding author. Address: Department of Child Neurology, Policlinico Gemelli, Largo Gemelli, Roma 00168, Italy. Tel.: +39 06 30155340; fax: +39 06 30154363. E-mail address: mercuri@rm.unicatt.it (E. Mercuri). www.elsevier.com/locate/nmd Available online at www.sciencedirect.com Neuromuscular Disorders 23 (2013) 624–628