RT Journal Article
SR Electronic
T1 Peak oxygen uptake and mortality in children with cystic fibrosis
JF Thorax
JO Thorax
FD BMJ Publishing Group Ltd and British Thoracic Society
SP 50
OP 54
DO 10.1136/thx.2003.008102
VO 60
IS 1
A1 Pianosi, P
A1 LeBlanc, J
A1 Almudevar, A
YR 2005
UL http://thorax.bmj.com/content/60/1/50.abstract
AB Background: Single measurements of peak oxygen uptake (V˙o2) have been shown to predict mortality in patients with cystic fibrosis (CF) although no longitudinal study of serial measurements has been reported in children. A study was undertaken to determine whether the initial, final, or the rate of fall of forced expiratory volume in 1 second (FEV1) or peak V˙o2 was a better predictor of mortality. Methods: Twenty eight children aged 8–17 years with CF performed annual pulmonary function and maximal exercise tests over a 5 year period to determine FEV1 and peak V˙o2, magnitude of their change over time, and survival over the subsequent 7–8 years. Analysis was done using Kaplan-Meier curves and Cox proportional hazard model. Results: Peak V˙o2 fell during the observation period in 70% of the patients, with a mean annual decline of 2.1 ml/min/kg. Initial peak V˙o2 was not predictive of mortality but rate of decline and final peak V˙o2 of the series were significant predictors. Patients with peak V˙o2 less than 32 ml/min/kg exhibited a dramatic increase in mortality, in contrast to those whose peak V˙o2 exceeded 45 ml/min/kg, none of whom died. The first, last, and rate of decline in FEV1 over time were all significant predictors of mortality. Conclusions: Higher peak V˙o2 is a marker for longer survival in CF patients.