Self-reported exercise and longitudinal outcomes in cystic fibrosis: a retrospective cohort study

Abstract

BackgroundCystic fibrosis (CF) is characterized by recurrent respiratory infections and progressive lung disease. Whereas exercise may contribute to preserving lung function, its benefit is difficult to ascertain given the selection bias of healthier patients being more predisposed to exercise. Our objective was to examine the role of self-reported exercise with longitudinal lung function and body mass index (BMI) measures in CF.MethodsA total of 1038 subjects with CF were recruited through the U.S. CF Twin-Sibling Study. Questionnaires were used to determine exercise habits. Questionnaires, chart review, and U.S. CF Foundation Patient Registry data were used to track outcomes.ResultsWithin the study sample 75% of subjects self-reported regular exercise. Exercise was associated with an older age of diagnosis (p = 0.002), older age at the time of ascertainment (p < 0.001), and higher baseline FEV1 (p = 0.001), but not CFTR genotype (p = 0.64) or exocrine pancreatic function (p = 0.19). In adjusted mixed models, exercise was associated with both a reduced decline in FEV1 (p < 0.001) and BMI Z-score (p = 0.001) for adults, but not children aged 10–17 years old.ConclusionsIn our retrospective study, self-reported exercise was associated with improved longitudinal nutritional and pulmonary outcomes in cystic fibrosis for adults. Although prospective studies are needed to confirm these associations, programs to promote regular exercise among individuals with cystic fibrosis would be beneficial.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2466-14-159) contains supplementary material, which is available to authorized users.

Perspective on cystic fibrosis and physical activity: Is there a difference compared to healthy individuals?

“…Interestingly, regular exercise was associated with a reduced FEV1 decline in the adult participants but not in children aged 10-17 years old. 29 Schneidermann et al 4 nicely reproduced this positive effect of regular physical activity on lung function decline in a longitudinal study. The Habitual Activity Estimation Scale (HAES) was completed at each quarterly clinical visit in 212 children aged 7-17 years over a period of 9 years.…”

“…Participation in regular exercise was associated with older age at the time of study and a higher FEV1 but not with CFTR genotype or exocrine pancreatic function. Interestingly, regular exercise was associated with a reduced FEV1 decline in the adult participants but not in children aged 10–17 years old . Schneidermann et al nicely reproduced this positive effect of regular physical activity on lung function decline in a longitudinal study.…”

“…By including patients in a large age range we expected larger ranges of disease state (i.e., lung function) and a greater variability in the time spent in strenuous and very strenuous physical activity leading to a higher likelihood of associations to become stronger. Most of the previous work was done in school‐aged children and adolescents with ages ranging between 6 and 19 years with heterogeneous results. All but one of these studies did not differentiate between different age groups.…”

Cystic fibrosis lung environment and Pseudomonas aeruginosa infection

“…Exercise has been shown to influence lung function positively in CF patients if carried out in a beneficial, safe and monitored environment [191, 192]. Spiritual factors interestingly have been shown to contribute positively on treatment adherence in CF patients [193].…”

Accumulating physical activity in at least 10-minute bouts predicts better lung function after 3-years in adults with cystic fibrosis

“…Very few studies have reported on the long-term relationship between physical activity and clinical outcomes, in particular lung function, in people with CF. C ollaco et al [ 11 ], using US CF Foundation patient registry data, found adults who self-reported any exercise participation had a slower rate of decline in FEV 1 over 5 years. In a predominantly paediatric cohort, participants who were categorised as having higher levels of activity, based on self-report using the Habitual Activity Estimation Scale, had a slower rate of decline in FEV 1 over an average of 5-years of follow-up [ 2 ].…”