title: Observational study of spinal muscular atrophy type 2 and 3: functional outcomes over 1 year.
abstract: OBJECTIVE
  To characterize the short-term course of spinal muscular atrophy (SMA) in a genetically and clinically well-defined cohort of patients with SMA.
  
  
  METHODS
  A comprehensive multicenter, longitudinal, observational study.
  
  
  METHODS
  The Pediatric Neuromuscular Clinical Research Network for SMA, a consortium of clinical investigators at 3 clinical sites.
  
  
  METHODS
  Sixty-five participants with SMA types 2 and 3, aged 20 months to 45 years, were prospectively evaluated.
  
  
  METHODS
  We collected demographic and medical history information and determined the SMN 2 copy number.
  
  
  METHODS
  Clinical outcomes included measures of motor function (Gross Motor Function Measure and expanded Hammersmith Functional Motor Scale), pulmonary function (forced vital capacity), and muscle strength (myometry). Participants were evaluated every 2 months for the initial 6 months and every 3 months for the subsequent 6 months. We evaluated change over 12 months for all clinical outcomes and examined potential correlates of change over time including age, sex, SMA type, ambulatory status, SMN2 copy number, medication use, and baseline function.
  
  
  RESULTS
  There were no significant changes over 12 months in motor function, pulmonary function, and muscle strength measures. There was evidence of motor function gain in ambulatory patients, especially in those children younger than 5 years. Scoliosis surgery during the observation period led to a subsequent decline in motor function.
  
  
  CONCLUSIONS
  Our results confirm previous clinical reports suggesting that SMA types 2 and 3 represent chronic phenotypes that have relatively stable clinical courses. We did not detect any measurable clinical disease progression in SMA types 2 and 3 over 12 months, suggesting that clinical trials will have to be designed to measure improvement rather than stabilization of disease progression.
authors.affiliation: Department of Neurology, Columbia University, 710 W 168th St, 2nd Floor, New York, NY 10032, USA.
authors.forename: Petra
authors.initials: P
authors.lastname: Kaufmann
authors.forename: Michael P
authors.initials: MP
authors.lastname: McDermott
authors.forename: Basil T
authors.initials: BT
authors.lastname: Darras
authors.forename: Richard
authors.initials: R
authors.lastname: Finkel
authors.forename: Peter
authors.initials: P
authors.lastname: Kang
authors.forename: Maryam
authors.initials: M
authors.lastname: Oskoui
authors.forename: Andrei
authors.initials: A
authors.lastname: Constantinescu
authors.forename: Douglas Michael
authors.initials: DM
authors.lastname: Sproule
authors.forename: A Reghan
authors.initials: AR
authors.lastname: Foley
authors.forename: Michele
authors.initials: M
authors.lastname: Yang
authors.forename: Rabi
authors.initials: R
authors.lastname: Tawil
authors.forename: Wendy
authors.initials: W
authors.lastname: Chung
authors.forename: Bill
authors.initials: B
authors.lastname: Martens
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Montes
authors.forename: Jessica
authors.initials: J
authors.lastname: O'Hagen
authors.forename: Sally
authors.initials: S
authors.lastname: Dunaway
authors.forename: Jean M
authors.initials: JM
authors.lastname: Flickinger
authors.forename: Janet
authors.initials: J
authors.lastname: Quigley
authors.forename: Susan
authors.initials: S
authors.lastname: Riley
authors.forename: Allan M
authors.initials: AM
authors.lastname: Glanzman
authors.forename: Maryjane
authors.initials: M
authors.lastname: Benton
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Ryan
authors.forename: Carrie
authors.initials: C
authors.lastname: Irvine
authors.forename: Christine L
authors.initials: CL
authors.lastname: Annis
authors.forename: Hailly
authors.initials: H
authors.lastname: Butler
authors.forename: Jayson
authors.initials: J
authors.lastname: Caracciolo
authors.forename: Megan
authors.initials: M
authors.lastname: Montgomery
authors.forename: Jonathan
authors.initials: J
authors.lastname: Marra
authors.forename: Benjamin
authors.initials: B
authors.lastname: Koo
authors.forename: Darryl C
authors.initials: DC
authors.lastname: De Vivo
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D014897:Spinal Muscular Atrophies of Childhood / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology*; D055815:Young Adult