Quality of life is associated with physical activity and fitness in cystic fibrosis.

BACKGROUND: Health-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. METHODS: Baseline (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. RESULTS: Peak 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). CONCLUSIONS: HRQoL 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 REGISTRATION: ClinicalTrials.gov, NCT00231686.

Effect of supervised training on FEV1 in cystic fibrosis: a randomised controlled trial.

BACKGROUND: Long-term exercise interventions have been shown to improve vital capacity in cystic fibrosis (CF). Yet, no data are available indicating positive effects of long-term exercise training on FEV1. METHODS: 39 Swiss patients with CF were randomly divided into strength training (ST, n=12), endurance training (AT, n=17) and controls (CON(CH), n=10), and also compared with age-matched Swiss (n=35) and German (n=701) CF registry data. A partially supervised training of 3×30 min/week for 6 months took place with measurements at baseline and after 3, 6, 12 and 24 months. Primary outcome was FEV1 at 6 months. RESULTS: FEV1 increased significantly in both training groups compared with CON(CH) (AT:+5.8±0.95, ST:+7.4±2.5, CON(CH):-11.5±2.7% predicted, p<0.001) and both registry groups at 6 months. At 24 months, changes in favour of the training groups persisted marginally compared with CONCH, but not compared with registry data. CONCLUSIONS: 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.