Donna L. Wilkes

Exercise and physical activity in children with cystic fibrosis

Regular exercise and habitual physical activity are important for patients with cystic fibrosis (CF). Research has demonstrated the benefits of aerobic, anaerobic, and strength exercise training programs for health and quality of life, however, the CF patient is faced with unique barriers and challenges to participation. Recently, increased levels of habitual physical activity have been shown to slow the decline in lung function in patients with CF, and regular participation in a variety of activities may result in greater adherence in the long term. Research is now available to justify the incorporation of exercise into the routine care of patients with CF. This paper provides the background and rationale for the implementation of exercise and habitual physical activity recommendations by the health care team. Education of health care providers regarding the importance of exercise and habitual physical activity for patients with CF is needed in order for exercise and physical activity to be incorporated as key components of clinical practice and into the lives of patients with CF.

Reliability and validity of the habitual activity estimation scale (HAES) in patients with cystic fibrosis

To understand potential benefits of exercise in the cystic fibrosis (CF) population, there needs to be accurate methods to quantify it. The Habitual Activity Estimation Scale (HAES) questionnaire has been shown to be a feasible tool to measure physical activity however the reliability and validity have yet to be determined in the CF population.

Skeletal Muscle Metabolism in Cystic Fibrosis and Primary Ciliary Dyskinesia

Previous studies have reported differences in muscle function and metabolism between patients with cystic fibrosis (CF) and healthy controls (HC), but it is currently unknown whether these abnormalities are specific to CF or also seen in other airway diseases. In this study, we used magnetic resonance spectroscopy (MRS) during exercise to assess muscle metabolism in CF patients. Twenty patients with CF and 20 age, gender, and habitual activity-matched HCs and a respiratory disease comparison group with primary ciliary dyskinesia (PCD; n = 10) were studied. 31Phosphorus MRS (31P-MRS) was used to characterize muscle bioenergetic metabolism at rest and after high-, moderate-, and low-intensity exercise. CF patients exhibited lower resting ATP/phosphocreatine (PCr) ratio and significantly higher end-exercise pH values compared with both HC and PCD patients. Both CF and PCD patients demonstrated significantly slower PCr recovery time constants after high-intensity exercise. Our results suggest that not only there are specific abnormalities of muscle metabolism in CF patients but also there is a nonspecific impact of respiratory disease on muscle function.

Longitudinal Relationship between Physical Activity and Lung Health in Patients with Cystic Fibrosis

Exercise is beneficial for patients with cystic fibrosis (CF) but long-term effects of physical activity on lung function evolution are unknown. We evaluated the longitudinal relationship between changes in habitual physical activity (HPA) and rate of decline in lung function in patients with CF. We tracked HPA using the Habitual Activity Estimation Scale, forced expiratory volume in 1 s (FEV1) and Stage I exercise tests in 212 patients with CF over a 9-year period. Adjusting for sex, baseline age and FEV1, mucoid Pseudomonas aeruginosa and CF-related diabetes, mean±sd FEV1 % predicted decreased by 1.63±0.08% per year (p<0.0001) while mean±sd HPA increased by 0.28±0.03 h·day−1 per year (p<0.0001) over the study period. A greater increase in HPA was associated with a slower rate of decline in FEV1 (r=0.19, p<0.0069). Dividing subjects into “high” and “low” activity (above or below the mean rate of change of activity, respectively), a steeper rate of FEV1 decline was observed for low (-1.90% per year) compared to high (-1.39% per year) (p=0.002). Increases in HPA are feasible despite progression of lung disease and are associated with a slower rate of decline in FEV1, highlighting the benefit of regular physical activity, and its positive impact on lung function in patients with CF. FEV1 declines at a lesser rate in patients with cystic fibrosis who increase their activity levels http://ow.ly/rETZc

Assessment of Body Composition in Pediatric Patients With Cystic Fibrosis

Cystic fibrosis (CF) leads to pathological changes in organs that express the cystic fibrosis transmembrane conductance regulator (CFTR), including secretory cells of the digestive tract and the pancreas. Maintaining nutritional sufficiency is challenging for CF patients and therefore accurate monitoring is important for their clinical management.

Physiological correlates of pulmonary function in children with cystic fibrosis

Although peak aerobic capacity (VO2peak) has been linked to outcome in patients with cystic fibrosis (CF), measuring is time consuming, and requires expensive equipment and expertise that is not readily available in all centers. Other fitness parameters such as peak anaerobic power, measures of power and strength may be simpler to deliver in the clinic. The relationship between these measures and established outcomes such as forced expiratory volume in one second (FEV1) and peak aerobic power (VO2peak) in CF remains unclear. Therefore we evaluated (a) aerobic fitness, (b) anaerobic fitness, and (c) upper and lower body muscle strength to determine their relationship to FEV1 and VO2peak in children with CF.