Benefits of combining inspiratory muscle with 'whole muscle' training in children with cystic fibrosis: a randomised controlled trial.

BACKGROUND: The purpose of this study (randomised controlled trial) was to assess the effects of an 8-week combined 'whole muscle' (resistance+aerobic) and inspiratory muscle training (IMT) on lung volume, inspiratory muscle strength (PImax) and cardiorespiratory fitness (VO2 peak) (primary outcomes), and dynamic muscle strength, body composition and quality of life in paediatric outpatients with CF (cystic fibrosis, secondary outcomes). We also determined the effects of a detraining period. METHODS: Participants were randomly allocated with a block on gender to a control (standard therapy) or intervention group (initial n=10 (6 boys) in each group; age 10±1 and 11±1 years). The latter group performed a combined programme (IMT (2 sessions/day) and aerobic+strength exercises (3 days/week, in-hospital)) that was followed by a 4-week detraining period. All participants were evaluated at baseline, post-training and detraining. RESULTS: Adherence to the training programme averaged 97.5%±1.7%. There was a significant interaction (group×time) effect for PImax, VO2peak and five-repetition maximum strength (leg-press, bench-press, seated-row) (all (p<0.001), and also for %fat (p<0.023) and %fat-free mass (p=0.001), with training exerting a significant beneficial effect only in the intervention group, which was maintained after detraining for PImax and leg-press. CONCLUSION: The relatively short-term (8-week) training programme used here induced significant benefits in important health phenotypes of paediatric patients with CF. IMT is an easily applicable intervention that could be included, together with supervised exercise training in the standard care of these patients.

Comparison of physical fitness between healthy and mild-to-moderate asthmatic children with exercise symptoms: A cross-sectional study.

OBJECTIVE: Asthma is a chronic disease that may affect physical fitness, although its primary effects on exercise capacity, muscle strength, functionality and lifestyle, in children and adolescents, are still poorly understood. This study aimed to evaluate the differences in cardiorespiratory fitness, muscle strength, lifestyle, lung function, and functionality between asthmatics with exercise symptoms and healthy children. In addition, we have analyzed the association between clinical history and the presence of asthma. STUDY DESIGN: Cross-sectional study including 71 patients with a diagnosis of asthma and 71 healthy children and adolescents (7-17 years of age). Anthropometric data, clinical history, disease control, lifestyle (KIDMED and physical activity questionnaires), lung function (spirometry), exercise-induced bronchoconstriction test, aerobic fitness (cardiopulmonary exercise test), muscle strength and functionality (timed up and go; timed up and down stairs) were evaluated. RESULTS: Seventy-one patients with asthma (mean age 11.5 ± 2.7) and 71 healthy subjects (mean age 10.7 ± 2.5) were included. All asthmatic children had mild to moderate and stable asthma. EIB occurred in 56.3% of asthmatic children. Lung function was significantly (p < .05) lower in the asthmatic group when compared to healthy peers, as well as the cardiorespiratory fitness, muscle strength, lifestyle and functionality. Moreover, asthmatic children were more likely to have atopic dermatitis, allergic reactions, food allergies, and a family history of asthma when compared to healthy children. CONCLUSIONS: Children with mild-to-moderate asthma presenting exercise symptoms show a reduction in cardiorespiratory fitness, muscle strength, lung function, functionality, and lifestyle when compared to healthy peers. The study provides data for pediatricians to support exercise practice aiming to improve prognosis and quality of life in asthmatic children.

Prevalence of sleep-disordered breathing in children with Down syndrome: polygraphic findings in 108 children.

STUDY OBJECTIVES: To assess the prevalence of sleep-disordered breathing in a nonselected group of children with Down syndrome and to determine significant predisposing factors for this condition. DESIGN: Prospective study. SETTING: Tertiary care university hospital in Madrid, Spain. PATIENTS: The study population included 108 consecutive children with Down syndrome (mean [SD] age, 7.9 [4.5] years; range, 1-18 years) independently of whether or not suggestive clinical features of sleep-disordered breathing were present. INTERVENTIONS: In addition to history, physical examination, and lateral radiographs of the nasopharynx, all participants underwent an overnight cardiorespiratory polygraphy at the hospital using a portable ambulatory device (Apnoescreen II plus). An apnea-hypopnea index of at least 3 was required for defining the presence of sleep-disordered breathing. RESULTS: The prevalence of sleep-disordered breathing was 54.6%, with a significantly higher prevalence in boys (64.7%) than in girls (38.5%) (P < .05). The group with sleep-disordered breathing was significantly younger (6.4 [3.9] years) than those with normal polysomnographic recordings (9.6 [4.6] years) (P < .001). In the multivariate analysis, age (less than 8 years old) (odds ratio [OR], 3.36; 95% confidence interval [CI], 1.40, 8.06); male sex (OR, 3.32; 95% CI, 1.32, 8.12); and tonsillar hyperplasia (OR, 5.24; 95% CI, 1.52, 19.03) were significantly associated with sleep-disordered breathing. Body mass index, adenoid hyperplasia, previous tonsillectomy or adenoidectomy, congenital heart disease, malocclusion, and macroglossia did not affect the prevalence of sleep-disordered breathing. CONCLUSIONS: The prevalence of sleep-disordered breathing in children with Down syndrome is very high, particularly in boys. Tonsillar hyperplasia may play a role in the pathophysiology of sleep-disordered breathing in these patients. Adenoid hyperplasia, obesity, and congenital heart disease were not important risk factors for sleep-disordered breathing.

Aerobic fitness is associated with lower risk of hospitalization in children with cystic fibrosis.

BACKGROUND: Children with cystic fibrosis (CF) often have to be hospitalized because of acute exacerbation of their respiratory symptoms. Given the fact that improved peak oxygen uptake (VO2peak ) is positively associated with lung function and overall health in children with CF, this study examined the association between VO2peak and the need for hospitalization in a cohort of pediatric CF patients. METHODS: In a 3-year study, 77 CF children with mild-to-moderately severe CF (forced expiratory volume in 1 sec [FEV1 ] ≥ 50%) underwent a maximal exercise test to determine VO2peak . Anthropometric, lung function and muscle strength measurements were also conducted and dates of hospitalization were recorded for the study period. Associations were then determined between the variables recorded and hospitalization by univariate and multivariate Cox proportional hazards regression analyses. RESULTS: VO2peak was 38.6 ± 6.7 ml kg(-1) min(-1) for boys and 31.9 ± 6.9 ml kg(-1) min(-1) for girls. In multivariate analyses, VO2peak was the only variable significantly associated with time to hospitalization (hazard ratio 0.91, P = 0.03). CONCLUSION: A significant association was detected between greater aerobic fitness, and lower risk of hospitalization. Because hospitalization due to respiratory exacerbation is a powerful prognostic factor, our findings provide further support for the importance of aerobic fitness evaluation in the management of children with mild-to-moderately severe CF.

Right ventricular dysfunction in adolescents with mild cystic fibrosis.

BACKGROUND: In cystic fibrosis (CF) patients the right ventricle (RV) suffers a progressive deterioration, but it is not clear when these changes begin. The aim of this study was to analyze the RV function in CF patients with mild respiratory disease. METHODS: Color-Doppler-Echocardiographic studies were prospectively performed in CF adolescent patients and an age-matched control group. Findings were correlated with pulmonary function tests (PFT), genotype, chronic bacterial colonization, pancreatic status and clinical scores. Only patients with mild CF were selected. RESULTS: Thirty seven CF patients and 40 healthy controls were recruited. In CF patients all echocardiographic parameters were abnormal compared to controls. Doppler analysis showed slightly elevated pulmonary artery pressure values, and abnormal relaxation and systolic function for all indexes. No correlation was found with any of the features studied. CONCLUSIONS: In CF patients, abnormalities in the structure and function of the RV may be present at early stages of the disease. These abnormalities are subclinical and do not correlate with clinical scores, PFT, genotype, chronic bacterial colonization or pancreatic insufficiency.

Intrahospital weight and aerobic training in children with cystic fibrosis: a randomized controlled trial.

PURPOSE: The purpose of our study was to assess the effects of an 8-wk intrahospital combined circuit weight and aerobic training program performed by children with cystic fibrosis (of low-moderate severity and stable clinical condition) on the following outcomes: cardiorespiratory fitness (VO2peak) and muscle strength (five-repetition maximum (5RM) bench press, 5RM leg press, and 5RM seated row) (primary outcomes) and pulmonary function (forced vital capacity, forced expiratory volume in 1 s), weight, body composition, functional mobility (Timed Up and Down Stairs and 3-m Timed Up and Go tests), and quality of life (secondary outcomes). We also determined the effects of a detraining period (4 wk) on the aforementioned outcomes. METHODS: We performed a randomized controlled trial design. Eleven participants in each group (controls: 7 boys, age = 11 ± 3 yr, body mass index = 17.2 ± 0.8 kg · m(-2) (mean ± SEM); intervention: 6 boys, age = 10 ± 2 yr, body mass index = 18.4 ± 1.0 kg · m(-2)) started the study. RESULTS: Adherence to training averaged 95.1% ± 7.4%. We observed a significant group × time interaction effect (P = 0.036) for VO2peak. In the intervention group, VO2peak significantly increased with training by 3.9 mL · kg(-1) · min(-1) (95% confidence interval = 1.8-6.1 mL · kg(-1) · min(-1), P = 0.002), whereas it decreased during the detraining period (-3.4 mL · kg(-1) · min(-1), 95% confidence interval = -5.7 to -1.7 mL · kg(-1) · min(-1), P = 0.001). In contrast, no significant changes were observed during the study period within the control group. Although significant improvements were also observed after training for all 5RM strength tests (P < 0.001 for the interaction effect), the training improvements were not significantly decreased after the detraining period in the intervention group (all P > 0.1 for after training vs detraining). We found no significant training benefits in any of the secondary outcomes. CONCLUSIONS: A short-term combined circuit weight and aerobic training program performed in a hospital setting induces significant benefits in the cardiorespiratory fitness and muscle strength of children with cystic fibrosis.