ABSTRACT
OBJECTIVE: As aerobic exercise capacity, as defined by VO2max, is associated with patient functioning and possibly prognosis in cystic fibrosis (CF), correlations between VO2max phenotype and genotype may be of value. DESIGN: Retrospective clinical series. SETTING: Cystic fibrosis referral clinic. PATIENTS: Convenience sample of 35 patients with CF consecutively referred for exercise testing. MAIN OUTCOME MEASURES: Blood samples were examined for mutations of cystic fibrosis transmembrane regulator (CFTR), Height, wight, pulmonary function, resting-energy expenditure, VO2max, and other exercise variables were assessed in each referred patient. RESULTS: Statistical comparison of 10 patients who were homozygous for the dF508 mutation of CFTR with 20 patients heterozygous for dF508 revealed no significant differences for height, weight, pulmonary function, resting-energy expenditure, VO2max, or any other exercise variables. CONCLUSIONS: These results imply a limited effect of the mutation status on overall patient functioning and prognosis. Future identification of more rare CFTR mutations and other genes and subsequent classification of patients in a manner reflective of the cellular physiology may lead to different results.
