title: Adults with Down syndrome have reduced cardiac response after light exercise testing.
abstract: OBJECTIVE
  Physical fitness is reduced in adults with Down syndrome (DS). The present study was conducted to elucidate the exercise response in adults with DS.
  
  
  METHODS
  Case controlled before-after trial.
  
  
  METHODS
  Residential centre for people with intellectual disabilities.
  
  
  METHODS
  96 Adults with DS, 25 non-DS adults with an intellectual disability, 33 controls.
  
  
  METHODS
  Echocardiography to exclude heart defects and to measure cardiac index (CI) in the supine position, supine position with raised legs, and following ten knee bends.
  
  
  METHODS
  Exercise testing
  
  
  RESULTS
  At rest, mean CI was not significantly different between persons with DS and controls (2.3 vs. 2.4 l/min/m(2), p = 0.3). However, mean CI after exercise was significantly lower in DS (2.9 vs. 3.7 l/min/m(2), p < 0.001) and mean CI increase from rest to exercise was more than 50% lower in DS. On the contrary, CI after exercise was similar among controls and non-DS adults with an intellectual disability. Significantly lower stroke volumes in DS were found with insufficient heart rate response.
  
  
  CONCLUSIONS
  CI at rest was similar in adults with DS and controls; however persons with DS have a diminished cardiac response to exercise. Stroke volumes were significantly lower in DS during exercise and a compensated heightened heart rate was absent.
authors.affiliation: Department of Cardiology, Academic Medical Centre, Meibergdreef 9, 1105 AZ, Amsterdam, the Netherlands.
authors.forename: J C
authors.initials: JC
authors.lastname: Vis
authors.forename: H A C M
authors.initials: HA
authors.lastname: De Bruin-Bon
authors.forename: B J
authors.initials: BJ
authors.lastname: Bouma
authors.forename: S A
authors.initials: SA
authors.lastname: Huisman
authors.forename: L
authors.initials: L
authors.lastname: Imschoot
authors.forename: K
authors.initials: K
authors.lastname: van den Brink
authors.forename: B J M
authors.initials: BJ
authors.lastname: Mulder