Little is known about the long-term persistence of positive effects induced by a physical conditioning programme in cystic fibrosis. Therefore, this study determined the effects of a 6-month conditioning programme on peak oxygen uptake (primary outcome) and other markers of fitness, physical activity, anthropometry, lung function and quality of life (secondary outcomes), 18 and 24 months after the programme was initiated.Patients with cystic fibrosis aged 12-40 yrs were randomly assigned to an intervention (n523) and a control (n515) group. The intervention group consented to add 3 h of sports per week for o6 months to their previous activities. Controls were asked to maintain their level of activity for 12 months. Patients were seen at baseline and after 3, 6, 12, 18 and 24 months.There was no significant difference between groups at baseline. The intervention induced positive effects on peak oxygen uptake (difference in changes from baseline to the 18-and 24-month assessments between groups: 3.72¡1. ; p,0.05), forced vital capacity (6.06¡2.87% predicted; p,0.05) and perceived health (9.89¡4.72; p,0.05).A home-based partially supervised physical conditioning programme can improve physical fitness, lung function and perceived health long after the intervention has ended.

RATIONALE: The prognostic value of cardiopulmonary exercise testing (CPET) for survival in cystic fibrosis (CF) in the context of current clinical management, when controlling for other known prognostic factors is unclear. OBJECTIVES: To determine the prognostic value of CPET-derived measures beyond peak oxygen uptake (VO2peak) following rigorous adjustment for other predictors. MEASUREMENTS AND MAIN RESULTS: Data from 10 CF-centers in Australia, Europe and North America were collected retrospectively. 510 patients completed a cycle CPET between January 2000 and December 2007, of which 433 fulfilled the criteria for a maximal effort. Time to death/lung transplantation (LTx) was analyzed using Cox proportional hazards regression. In addition, phenotyping using hirarchical Ward's clustering was performed to characterize high risk subgroups. Cox regression showed-even after adjustment for sex, forced expiratory volume in 1s (%predicted), body mass index (z-score), age at CPET, Pseudomonas aeruginosa status, and CF-related diabetes as covariates in the model-that VO2peak in %predicted, hazard ratio (HR) 0.964 [95%-CI: 0.944-0.986], peak work rate (%predicted, HR 0.969 [0.951-0.988], ventilatory equivalent for oxygen (VE/VO2peak) HR 1.085 [1.041-1.132], and carbon dioxide (VE/VCO2peak), HR 1.060 [1.007-1.115], all P<0.05) were significant predictors of death or LTx at 10 years follow-up. Phenotyping revealed that CPET-derived measures were important for clustering. We identified a high risk cluster characterized by poor lung function, nutritional status and exercise capacity. CONCLUSIONS: In conclusion, CPET provides additional prognostic information to established predictors of death/LTx in CF. High risk patients may especially benefit from regular monitoring of exercise capacity and exercise counselling.

Indirect qualitative MRI of pulmonary function is feasible using the paramagnetic effects of oxygen physically dissolved in blood. In this study, a more quantitative oxygen-enhanced pulmonary function test based on the slope of a plot of R 1 vs. oxygen concentration-the oxygen transfer function (OTF)-was developed and tested in a pool of five healthy volunteers and five patients with cystic fibrosis (CF). The lung T 1 relaxation rate, R 1 , under normoxic conditions (room air, 21% O 2 ), and the response to various hyperoxic conditions (40%-100% O 2 ) were studied. Lung T 1 in healthy volunteers showed a relatively homogeneous distribution while they breathed room air, and a homogeneous decrease under hyperoxic conditions. Lung T 1 in CF patients showed an inhomogeneous distribution while they breathed room air, and the observed lung Oxygen plays a critical role in the physiology and pathophysiology of the lung. The ability to detect and characterize altered lung oxygen uptake is of great potential value for clinical diagnoses. Thus, in general, functional studies of the human lung address ventilation and gas exchange processes, particularly those of oxygen. The direct use of oxygen as a contrast agent (CA) in an imaging setting would be an interesting means of assessing pulmonary function.Indirect MRI of pulmonary function based on the paramagnetic effects of oxygen physically dissolved in pulmonary blood was demonstrated for the first time by Edelman et al. (1). This pulmonary function test exploits the fact that the amount of dissolved oxygen in the pulmonary blood increases during breathing pure oxygen, resulting in significant signal enhancement in T 1 -weighted lung images. Since the effect of oxygen on the proton spins of blood water, rather than the oxygen molecules themselves, is detected by this method, the diffusion of oxygen from the alveoli to the capillaries of the lungs can only be indirectly measured. However, the diffusion of oxygen is not the only parameter that specifies the observed MR signal in this method, since ventilation-perfusion inequalities also directly affect the observed signal changes. Thus, it has been proposed (2) that different mechanisms, such as ventilation, perfusion, and diffusion, are potentially responsible for the observed signal changes. The major advantage of this oxygen-enhanced approach is its relatively simple experimental setup, since only standard hardware for proton imaging, a ventilatory mask system, and oxygen (which is widely available) as a paramagnetic CA are required. The main current limitations of this approach are that no signal changes are visible at certain T 1 values (i.e., regions without signal changes could mimic pathology, since T 1 is not homogeneous across the entire lung (3,4)), and a quantitative assessment of the pulmonary function is critical because only relative signal changes in T 1 -weighted images are detected. Therefore, quantitative T 1 measurements of oxygen-enhanced MR images have a higher potential for the diagnosis of lung diseas...

A partially supervised training over 6 months improved FEV1 but effects were basically gone 18 months off training. Regular long-term training should be promoted as essential part of treatment in CF.

BackgroundHealth-related and disease-specific quality of life (HRQoL) has been increasingly valued as relevant clinical parameter in cystic fibrosis (CF) clinical care and clinical trials. HRQoL measures should assess – among other domains – daily functioning from a patient’s perspective. However, validation studies for the most frequently used HRQoL questionnaire in CF, the Cystic Fibrosis Questionnaire (CFQ), have not included measures of physical activity or fitness. The objective of this study was, therefore, to determine the cross-sectional and longitudinal relationships between HRQoL, physical activity and fitness in patients with CF.MethodsBaseline (n = 76) and 6-month follow-up data (n = 70) from patients with CF (age ≥12 years, FEV1 ≥35%) were analysed. Patients participated in two multi-centre exercise intervention studies with identical assessment methodology. Outcome variables included HRQoL (German revised multi-dimensional disease-specific CFQ (CFQ-R)), body composition, pulmonary function, physical activity, short-term muscle power, and aerobic fitness by peak oxygen uptake and aerobic power.ResultsPeak oxygen uptake was positively related to 7 of 13 HRQoL scales cross-sectionally (r = 0.30-0.46). Muscle power (r = 0.25-0.32) and peak aerobic power (r = 0.24-0.35) were positively related to 4 scales each, and reported physical activity to 1 scale (r = 0.29). Changes in HRQoL-scores were directly and significantly related to changes in reported activity (r = 0.35-0.39), peak aerobic power (r = 0.31-0.34), and peak oxygen uptake (r = 0.26-0.37) in 3 scales each. Established associates of HRQoL such as FEV1 or body mass index correlated positively with fewer scales (all 0.24 < r < 0.55).ConclusionsHRQoL was associated with physical fitness, especially aerobic fitness, and to a lesser extent with reported physical activity. These findings underline the importance of physical fitness for HRQoL in CF and provide an additional rationale for exercise testing in this population.Trial registrationClinicalTrials.gov, NCT00231686