title: Walking capacity evaluated by the 6-minute walk test in spinal and bulbar muscular atrophy.
abstract: Spinal and bulbar muscular atrophy (SBMA) is an adult-onset motor neuron disease caused by a CAG repeat expansion in the androgen receptor gene. Because the progression of SBMA is slow, it is plausible to identify biomarkers that monitor disease course for therapeutic development. To verify whether the 6-min walk test (6MWT) is a biomarker of SBMA, we performed the 6MWT in 35 genetically confirmed patients and in 29 age-matched healthy controls. The walk distance covered within 6 min (6MWD) was significantly less in SBMA than it was in controls (323.3 +/- 143.9 m and 637.6 +/- 94.2 m, respectively; P < 0.001). In test-retest analysis, the intraclass correlation coefficient for the 6MWD was high in SBMA patients (r = 0.982). In a 1-year follow-up the 6MWD significantly decreased at a rate of 11.3% per year. Our observations suggest that the 6MWT is a biomarker that can be used to monitor progression of motor impairment in SBMA.
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: Masahisa
authors.initials: M
authors.lastname: Katsuno
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Banno
authors.forename: Keisuke
authors.initials: K
authors.lastname: Suzuki
authors.forename: Motoshi
authors.initials: M
authors.lastname: Kawashima
authors.forename: Naoki
authors.initials: N
authors.lastname: Atsuta
authors.forename: Mizuki
authors.initials: M
authors.lastname: Ito
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Watanabe
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Tanaka
authors.forename: Gen
authors.initials: G
authors.lastname: Sobue
mesh_terms: D000328:Adult; D000368:Aged; D010244:Bulbar Palsy, Progressive / Q000235:genetics / Q000503:physiopathology*; D005069:Evaluation Studies as Topic; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000235:genetics / Q000503:physiopathology*; D011944:Receptors, Androgen / Q000235:genetics; D015203:Reproducibility of Results; D019680:Trinucleotide Repeat Expansion; D016138:Walking / Q000502:physiology*
chemical_list: D011944:Receptors, Androgen