title: Increased postural sway in persons with multiple sclerosis during short-term exposure to warm ambient temperatures.
abstract: Multiple sclerosis (MS) is a neurological disease marked by demyelination and axonal loss. Individuals with MS experience increases in clinical signs and symptoms during heat exposure.
  
  
  
  To test the hypothesis that moderate heat exposure adversely affects postural sway in individuals with MS.
  
  
  
  Ten individuals with relapsing-remitting MS (50±8y) and nine controls (47±10y) were examined under a Thermal and a Time Control trial. Following a 30min thermoneutral baseline (25°C, 30% relative humidity (RH)), stand tests randomized with eyes open and closed, were performed. For Thermal, subjects were first exposed to 60min of heating (40°C, 30%RH) followed by 60min of cooling (20°C, 30%RH). For Time Control, subjects remained in a thermoneutral environment throughout. Stand tests were repeated at consistent times in both trials.
  
  
  
  No difference in skin and core temperatures between groups were observed for any trial (P>0.05). During heating, postural sway was higher in MS relative to control subjects (eyes open, P=0.03; eyes closed, P=0.011). No differences in postural sway, regardless of eye status, were observed during the Time Control trial for either group (P>0.05).
  
  
  
  These data demonstrate that exposure to a moderate heating environment increases postural sway in patients with MS.
authors.affiliation: Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital and UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Paula Y S
authors.initials: PYS
authors.lastname: Poh
authors.affiliation: Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital and UT Southwestern Medical Center, Dallas, TX, USA.
authors.forename: Amy N
authors.initials: AN
authors.lastname: Adams
authors.affiliation: Department of Applied Physiology and Wellness, Southern Methodist University, Dallas, TX, USA.
authors.forename: Mu
authors.initials: M
authors.lastname: Huang
authors.affiliation: Department of Applied Physiology and Wellness, Southern Methodist University, Dallas, TX, USA.
authors.forename: Dustin R
authors.initials: DR
authors.lastname: Allen
authors.affiliation: Department of Applied Physiology and Wellness, Southern Methodist University, Dallas, TX, USA.
authors.forename: Scott L
authors.initials: SL
authors.lastname: Davis
authors.affiliation: Neurology Consultants of Dallas, Texas Health Presbyterian Hospital, Dallas, TX, USA.
authors.forename: Anna S
authors.initials: AS
authors.lastname: Tseng
authors.affiliation: Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital and UT Southwestern Medical Center, Dallas, TX, USA. Electronic address: craigcrandall@texashealth.org.
authors.forename: Craig G
authors.initials: CG
authors.lastname: Crandall
mesh_terms: D001833:Body Temperature Regulation; D016022:Case-Control Studies; D005260:Female; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology*; D004856:Postural Balance
keywords: Balance; Environmental chamber; Force plate; Hyperthermia; Multiple sclerosis; Postural sway