Mannitol Challenge to Assess Therapy Response in Asthmatic Children: An Interventional Cohort Study.

Bronchial provocation tests, such as the mannitol challenge, can be performed to identify and quantify the severity of bronchial hyperresponsiveness in asthmatic patients. Studies of the mannitol challenge as a monitoring tool in asthmatic children are limited. Our primary aim was to compare the bronchial hyperresponsiveness to mannitol in treatment-naive asthmatic children between baseline and three months after receiving the indicated asthma prophylaxis. Twenty-three asthmatic patients aged 4-16 years were analyzed in this prospective cohort study. All subjects underwent the mannitol challenge at baseline and after three months of treatment with budesonide ± formoterol. The difference in the provocative dose of mannitol to induce a 15% drop in FEV1 (PD15) between baseline and follow-up, as well as its association with the presence of exercise-induced or nocturnal asthma symptoms, were evaluated. The PD15 value increased significantly post-treatment (228.5 mg [4.50-458.15]; p = 0.04). Independently of the evaluation time point, the PD15 values were significantly lower in the presence of nocturnal asthma symptoms (490 mg [122-635] vs. 635 mg [635-635]; p = 0.03), whereas there was no association between the PD15 value and the presence of exercise-induced asthma (p = 0.73). These results suggest that bronchial hyperresponsiveness to mannitol may be a potential monitoring tool in the pediatric asthmatic population, reflecting therapy response in children receiving prophylactic treatment.

The Fitter the Better? Cardiopulmonary Exercise Testing Can Predict Pulmonary Exacerbations in Cystic Fibrosis.

BACKGROUND: The role of cardiopulmonary exercise testing (CPET) in the assessment of prognosis in CF (cystic fibrosis) is crucial. However, as the overall survival of the disease becomes better, the need for examinations that can predict pulmonary exacerbations (PEx) and subsequent deterioration becomes evident. METHODS: Data from a 10-year follow up with CPET and spirometry of CF patients were used to evaluate whether CPET-derived parameters can be used as prognostic indexes for pulmonary exacerbations in patients with CF. Pulmonary exacerbations were recorded. We used a survival analysis through Cox Regression to assess the prognostic role of CPET parameters for PeX. CPET parameters and other variables such as sputum culture, age, and spirometry measurements were tested via multivariate cox models. RESULTS: During a 10-year period (2009-2019), 78 CF patients underwent CPET. Cox regression analysis revealed that VO2peak% (peak Oxygen Uptake predicted %) predicted (hazard ratio (HR), 0.988 (0.975, 1.000) p = 0.042) and PetCO2 (end-tidal CO2 at peak exercise) (HR 0.948 (0.913, 0.984) p = 0.005), while VE/VO2 and (respiratory equivalent for oxygen at peak exercise) (HR 1.032 (1.003, 1.062) p = 0.033) were significant predictors of pulmonary exacerbations in the short term after the CPET. Additionally, patients with VO2peak% predicted <60% had 4.5-times higher relative risk of having a PEx than those with higher exercise capacity. CONCLUSIONS: CPET can provide valuable information regarding upcoming pulmonary exacerbation in CF. Patients with VO2peak <60% are at great risk of subsequent deterioration. Regular follow up of CF patients with exercise testing can highlight their clinical image and direct therapeutic interventions.

Cardiorespiratory Fitness Predicted by Fibrinogen and Leptin Concentrations in Children with Obesity and Risk for Diabetes: A Cross-Sectional Study and a ROC Curve Analysis.

Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health. The ability to exercise is affected by adiposity, and this mechanism involves low-grade chronic inflammation and homeostatic stress produced mainly in adipocytes, which can result in abnormal adipokine secretion. To date, the gold standard for cardiorespiratory fitness assessment is considered to be the maximum oxygen uptake (VO2max). The aim of the present study was to assess the prognostic value of hematological parameters of childhood obesity, as potential predictors of cardiorespiratory fitness (VO2max), using a sample of children and adolescents with obesity and risk for diabetes. A total of 84 clinically healthy children and adolescents were recruited, of which 21 were considered lean, 22 overweight and 41 obese, with a mean age of 12.0 ± 1.9, 11.4 ± 2.0, and 11.2 ± 2.1 years old, in each weight status category, respectively. Age and sex did not differ between groups. Hematologic testing was performed after 12 h of fasting including glucose, serum lipids, insulin, hc-CRP, adiponectin, leptin and fibrinogen levels. Cardiorespiratory capacity for exercise was assessed to determine VO2max, using a cycle ergometer. The VO2max was negatively correlated with progressive strength to the BMIz (-0.656, p ≤ 0.001), hs-CRP (r = -0.341, p ≤ 0.002), glucose (r = -0.404, p ≤ 0.001) and insulin levels (r = -0.348, p ≤ 0.001), the homeostasis model assessment of insulin resistance (HOMA-IR) (r = -0.345, p ≤ 0.002), as well as to the leptin (r = -0.639, p ≤ 0.001) and fibrinogen concentrations (r = -0.520, p ≤ 0.001). The multivariate analysis revealed that only leptin and fibrinogen concentrations could predict the VO2max adjusted for the BMIz of participants. The receiver operating characteristic (ROC) curve for the diagnostic accuracy of leptin, hs-CRP and fibrinogen concentrations for the prediction of VO2max revealed a good diagnostic ability for all parameters, with leptin being the most promising one (area under the curve (AUC): 99%). The results verify that in children with obesity, VO2max may be predicted from hematological parameters (leptin and fibrinogen), possibly bypassing more invasive methods.

Exercise responses are related to structural lung damage in CF pulmonary disease.

INTRODUCTION: Early detection of lung disease is a primary objective in monitoring patients with Cystic Fibrosis (CF); High-Resolution-Computed-Tomography (HRCT) assesses structural damage. Spirometry and cardiopulmonary exercise testing are used for functional evaluation of CF lung disease. AIM: To evaluate the deterioration of exercise testing parameters over a 2-year period compared to the change of spirometry and HRCT parameters among CF patients. METHODS: Twenty-eight CF patients were evaluated with HRCT, spirometry, and exercise testing; 15 had two assessments with an interval of 2 years. Correlation analyses between Bhalla score parameters and functional measures were performed. RESULTS: Twenty-eight patients with CF (mean age 14.9 years, mean forced expiratory volume in 1 sec [FEV1 ] 83.2%) were evaluated. FEV1 was not found to change significantly in the 2-year period (P = 0.612). Both mean Bhalla score and mean peak oxygen consumption (VO2 peak %) deteriorated significantly (P = 0.014 and P = 0.026, respectively). VO2 peak and respiratory equivalents for O2 and CO2 at peak exercise were found to be significant predictors of Bhalla score (r = -0.477, P = 0.010; r = 0.461, P = 0.018; r = 0.402; P = 0.042, respectively). Anaerobic threshold was associated with changes in Bhalla score over the following 2 years. CONCLUSIONS: Exercise testing is more sensitive than spirometry to detect structural changes in CF lungs. Pediatr Pulmonol. 2016; 51:914-920. © 2016 Wiley Periodicals, Inc.

Long-term outcome of parapneumonic effusions in children: Lung function and exercise tolerance.

OBJECTIVES: a: To evaluate the long-term outcome of parapneumonic effusions (PPE) in children regarding lung function and exercise tolerance, (b) to investigate the role of bronchial asthma in the outcome of PPE. METHODS: The design of the study included 51 children with PPE, at least 2 years after the initial infection. They were divided in two groups. Group A (38 children) consisted of children with PPE but without asthma prior initial infection. Group B (13 children) included children with PPE and asthma prior infection. Thirty-six children were taken as healthy controls (group C). All children performed spirometry and a maximal incremental cardiopulmonary exercise test on cycle ergometer. RESULTS: Children of both groups (A and B) showed statistically significant lower values in FVC%, FEV1%, and FEV1 /FVC compared to controls (group C). Children of group B had also significant lower FEF(25-75%) values compared to controls. Children of group B had significant lower FEV1 /FVC values compared to group A. All children of the three groups showed no differences in maximal exercise capacity (VO2max). Children of group A had higher respiratory equivalent to oxygen (VE/VO2) during exercise compared to healthy subjects. CONCLUSIONS: There are small effects on lung function and exercise capacity in the long-term, among children with PPE, but of no clinical importance. Pre-existing bronchial asthma doesn't influence the outcome significantly.

Reduced exercise capacity in Greek children with mild to moderate obstructive sleep apnea syndrome.

INTRODUCTION: Obstructive sleep apnea syndrome (OSAS) is a common disease that is increasingly recognized among pediatric population. The exercise capacity of adults with OSAS has been demonstrated to be impaired, but there are no data about pediatric exercise response. AIM: The aim of this study was to evaluate cardiopulmonary response to exercise in children with OSAS and to correlate exercise capacity and severity of OSAS. METHODS: Twenty-seven children with habitual snoring (Group A) (mean age 10.5 ± 1.8 years) referred for overnight polysomnography and 13 apparently healthy controls (mean age 11 ± 1.5 years) were recruited. According to the apnea hypopnea index (AHI) group A consisted of 15 (55.6%) children with mild OSAS and 12 (44.4%) with moderate-severe OSAS. All children completed a maximal ramping cardiopulmonary exercise test (CPET) on cycle ergometer. RESULTS: According to CPET children with OSAS had significantly lower VO2max (40.3 ± 8.4 ml/kg/min vs. 47.6 ± 7.9 ml/kg/min, P = 0.013) significantly lower VO2max (%) (77.7 ± 15 vs. 92.9 ± 10.5, P = 0.002), lower maximum heart-rate at peak exercise (86.6 ± 8.8 beat/min vs. 90.6 ± 7.2 beat/min) and higher systolic blood pressure level at peak exercise (145 ± 27.4 mmHg vs. 143.92 ± 20 mmHg) compared to control group. CONCLUSION: The present study demonstrates that young patients with OSAS, even with mild OSAS, had reduced exercise capacity as compared to control group.