Cardiopulmonary Exercise Testing Provides Additional Prognostic Information in Cystic Fibrosis.

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 ( V. o2peak) following rigorous adjustment for other predictors. METHODS: Data from 10 CF centers in Australia, Europe, and North America were collected retrospectively. A total of 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 was analyzed using Cox proportional hazards regression. In addition, phenotyping using hierarchical Ward clustering was performed to characterize high-risk subgroups. MEASUREMENTS AND MAIN RESULTS: Cox regression showed, even after adjustment for sex, FEV1% predicted, body mass index (z-score), age at CPET, Pseudomonas aeruginosa status, and CF-related diabetes as covariates in the model, that V. o2peak in % predicted (hazard ratio [HR], 0.964; 95% confidence interval [CI], 0.944-0.986), peak work rate (% predicted; HR, 0.969; 95% CI, 0.951-0.988), ventilatory equivalent for oxygen (HR, 1.085; 95% CI, 1.041-1.132), and carbon dioxide (HR, 1.060; 95% CI, 1.007-1.115) (all P < 0.05) were significant predictors of death or lung transplantation at 10-year 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: CPET provides additional prognostic information to established predictors of death/lung transplantation in CF. High-risk patients may especially benefit from regular monitoring of exercise capacity and exercise counseling.

Cardiopulmonary data in response to 6 months of training in physically active adult patients with classic cystic fibrosis.

BACKGROUND: The optimal training mode for cystic fibrosis (CF) patients has not been defined. OBJECTIVE: This study aimed to investigate cardiopulmonary function before and after endurance (ET) or resistance training (RT) for 6 months. METHODS: Twenty physically active adult patients (8 females) with classic CF were enrolled for ET or RT for 3 months followed by 3 months of mixed training. Training was recorded by telemetry and in diaries and lasted 30-45 min, three times a week. Lung function and peak oxygen uptake (VO(2)) were measured. Mean +/- SD predicted percentage of forced expiratory volume in 1 s (FEV(1) %) was 91 +/- 21%; maximal workload (W) was 170 +/- 31 in females and 273 +/- 54 in males. RESULTS: Nineteen patients completed the program, 3 at a lower and 1 at a higher training frequency than required. Maximal heart rate remained unchanged during the 6 months. Maximal VO(2)(liters x min(-1)) was significantly correlated to FEV(1) in males at baseline and 6 months (p = 0.006 and p = 0.04, respectively). Changes in maximal workload and maximal VO(2) improved significantly with ET compared with RT. CONCLUSIONS: Physically active CF patients preserve good cardiopulmonary function into adulthood. The controlled training program did not lead to further improvement although ET induced larger changes than RT.

Muscular strength and function in patients with cystic fibrosis.

BACKGROUND: For 20 years, physical activity has been an important component in the treatment of cystic fibrosis (CF) patients in Sweden. Data concerning physical performance in terms of muscular strength in these patients are limited OBJECTIVE: To compare muscular strength and function in patients with CF with those aspects in a healthy control group (CG). DESIGN: Thirty-three patients with CF (16 women) aged 16 to 35 years and 20 healthy individuals matched for age and gender were included in the study. All participants had undertaken regular physical training two to three times per week. The following tests were performed: vertical jumping ability; hand-grip strength; abdominal strength; arm/shoulder strength; quadriceps muscle strength; and a functional test of leg muscle endurance. RESULTS: Patients with CF showed decreased muscle strength and function compared to control subjects (women: maximal hand-grip strength in the right [p = 0.02] and the left hand [p = 0.001]; sustained hand-grip strength in the left hand [p = 0.002]; and in leg muscle endurance [p = 0.02]; men: the number of sit-ups performed within 30 s [p = 0.03]; and left leg isokinetic quadriceps strength at 180 degrees per second [p = 0.02]). The differences were not related to pancreatic or pulmonary function. There was no significant difference between the CF group and the CG in any other test results. CONCLUSIONS: Our study showed few differences in muscular performance between patients with CF and healthy control subjects. Both groups had regular moderate-to-high activity levels. Further studies are needed to evaluate whether the small but significant differences might be related to metabolic abnormalities in skeletal muscles in CF patients.

Lung function in the aging Swedish cystic fibrosis population.

Swedish Cystic Fibrosis (CF) care follows international guidelines in general. The only difference in our CF care package since 25 years is the physiotherapy regimen. Airway clearance therapy has since the early 1980s, from the day of diagnosis, been based upon daily physical exercise in conjunction with techniques for transporting and evacuating mucus. Postural Drainage+/-percussion and vibration has not been used in any age. The aim of this study was to evaluate our CF care package. Lung function data from the start of the study and with a 3-year interval were collected in the entire Swedish CF population > or =7 years old. Data were analysed for the age groups 7-17 and > or =18 years of age. Change of lung function over the study period was calculated. The impact of chronic Pseudomonas aeruginosa (Pa) colonisation and basal FEV(1)%p was also evaluated in a linear mixed model. Data from 99% of the country-wide CF population were available at inclusion. Mean FEV(1)%p was 90+/-21 vs 73+/-26 in the different age groups and mean VC%p was 94+/-18 vs 91+/-20. Forty percent of the adult group was > or =30 years old. Overall, 41% were chronically Pa colonised. Mean annual FEV(1)%p rate of decline was 0.77 and 0.64 in the different age groups. Lung function among Swedish CF patients is good and annual rate of decline low, even in an old cohort. The large proportion of adult patients emphasises future demands on CF care.