Relationship between lung function and Modified Shuttle Test performance in adult patients with cystic fibrosis: a cross-sectional, retrospective study.
OBJECTIVE
To investigate the relationship between lung function and exercise capacity in adults with cystic fibrosis (CF), and to develop a CF-specific equation to predict Modified Shuttle Test (MST) performance from baseline data.


METHODS
Cross-sectional, retrospective study.


METHODS
Adult CF centre.


METHODS
One hundred and twenty-seven patients with CF [61 male; mean age 25 years (range 17 to 52 years), mean forced expiratory volume in 1second (FEV1) 56% predicted (range 15 to 124%)].


METHODS
MST and FEV1.


RESULTS
Overall, a moderate-to-good relationship was found between lung function and MST performance (walking distance vs FEV1% predicted: r=0.64, P=0.01). This relationship between FEV1 and MST shows an obvious threshold at an FEV1 of 67% predicted. Above this threshold, no significant association was observed between FEV1 and MST performance. However, a strong relationship (MST vs FEV1% predicted: r≥0.74, P<0.01 for men and r=0.79, P<0.01 for women) was found below an FEV1 of 67% predicted.


CONCLUSIONS
This study suggests that a strong association exists between lung function (FEV1% predicted) and MST (walking distance) in adult patients with moderate-to-severe CF (FEV1<67% predicted). A reference equation for MST performance was developed for those patients with FEV1 ≤67% predicted, providing a tool to make an a-priori prediction of MST walking distance.
University Medical Centre Utrecht, Rehabilitation, Nursing Science and Sport, University Hospital Utrecht, Utrecht, The Netherlands. Electronic address: W.R.Doeleman@umcutrecht.nl.
W R
WR
Doeleman
University Medical Centre Utrecht, Child Development and Exercise Centre, Wilhelmina Children's Hospital Utrecht, Utrecht, The Netherlands.
T
T
Takken
University Medical Centre Utrecht, Department of Pulmonology, Utrecht, The Netherlands.
I
I
Bronsveld
University Medical Centre Utrecht, Child Development and Exercise Centre, Wilhelmina Children's Hospital Utrecht, Utrecht, The Netherlands.
E H J
EH
Hulzebos
D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D055815:Young Adult
Cystic fibrosis; Exercise; Exercise test; Modified Shuttle Test