Impact of COVID-19 social distancing recommendations on pulmonary function, nutritional status, and morbidity in patients with cystic fibrosis

OBJECTIVE

To evaluate the impact of COVID-19 social distancing recommendations on nutritional status, pulmonary function, and morbidity in patients with cystic fibrosis (CF).

METHODS

A retrospective cohort study including patients older than six years with a diagnosis of CF was performed. Demographic and clinical data, anthropometric measurements, pulmonary function, days of antibiotic use, and length of hospital stay were recorded. Variables were recorded at three time points relative to the baseline for implementation of social distancing measures: T-1 (14 months before implementation), T0 (baseline), and T1 (14 months after implementation). Delta (Δ) was calculated for each period: Δ1 (pre-pandemic T0-T-1) and Δ2 (pandemic T1-T0).

RESULTS

The study included 25 patients, with a mean age of 11.7±4.3 years. The mean forced expiratory volume in the first second (FEV1) was 85.6±23.6%, and body mass index (BMI) was 17.5±3.0 kg/m2. When comparing the two periods (Δ1 and Δ2), there was a significant increase in the FEV1/forced vital capacity (FVC) ratio (p=0.013) and in the forced expiratory flow between 25 and 75% of vital capacity (FEF25-75%) (p=0.037) in the pandemic period. There was also a significant reduction (p=0.005) in the use of antibiotics in the pandemic period compared with the pre-pandemic period. The Δ1 and Δ2 values did not differ significantly for BMI, FEV1, or length of hospital stay.

CONCLUSIONS

COVID-19 social distancing recommendations had a positive impact (decrease) on morbidity (use of antibiotics) and small airway obstruction (FEF25-75%) in patients with CF.

Peripheral muscle strength is associated with aerobic fitness and use of antibiotics in patients with cystic fibrosis

AIMS

Individuals with cystic fibrosis (CF) may develop muscle abnormalities, although little is known on its clinical and functional impact. This study aimed to evaluate the association of peripheral muscle strength with aerobic fitness, habitual physical activity, lung function and the use of antibiotics (ATB) in patients with CF.

METHODS

A cross-sectional study where individuals aged ≥6 years underwent peripheral muscle strength evaluation (biceps, quadriceps and hamstrings) and performed a cardiopulmonary exercise test. Demographic, anthropometric, genetic, lung function and total days of ATB use within 1 year of tests were also collected.

RESULTS

Correlation was found for biceps (r = .45; P = .002) strength with the peak oxygen consumption (VO₂ peak). Muscle strength (biceps and quadriceps) also correlated with the ventilatory equivalent for oxygen consumption (V_E /VO₂ ) at anaerobic threshold (AT) and with the ventilatory equivalent for carbon dioxide production (V_E /VCO₂ ) both at AT and peak exercise. Negative correlations were found for quadriceps (r = -.39) and hamstrings (r = -.42) with the total days of ATB use in the following year. Patients needing to use ATB presented lower biceps strength (P = .05) and individuals with VO₂ peak lower than 37 mL·kg^-1 ·min^-1 presented lower muscle strength for both biceps (P = .01) and quadriceps (P = .02).

CONCLUSIONS

The results have shown that peripheral muscle strength is associated with aerobic fitness and the use of antibiotics in patients with CF.

Diagnostic performance of the physical activity-related question of the GINA questionnaire to detect exercise-induced bronchoconstriction in asthma

INTRODUCTION

The aim of the study was to evaluate the diagnostic performance of the item concerning physical activity of the Global Initiative for Asthma (GINA) asthma control questionnaire for detection of exercise-induced bronchoconstriction (EIB) in children and adolescents.

MATERIAL AND METHODS

We divided participants (aged 6-18 years) with a diagnosis of asthma into two groups according to the GINA severity classification: mild/moderate asthma (MMA) and severe therapy-resistant asthma (STRA). We collected anthropometric, clinical and functional data (spirometry) and performed an EIB test. We used item 4 of the GINA questionnaire regarding exercise-induced symptoms to assess the diagnostic power of this instrument.

RESULTS

We included 40 patients (17 with MMA and 23 with STRA) with a mean age of 11.3 years and a mean FEV₁z-score of -0.33, of who 13 (32.5%) were classified as having uncontrolled asthma. Of the patients with uncontrolled asthma, 7 (53.8%) exhibited a decrease in the FEV₁ after the EIB test. We found a higher frequency of EIB in participants with FEV₁ z-score values of less than -1.0 compared to those with a z-score of -1.0 or greater (P = .05). There were no significant differences in the frequency of EIB based on disease severity and control. We also found no association of item 4 (GINA) with EIB. The area under the ROC curve demonstrated that the discriminative power of the GINA questionnaire for the detection of EIB is inadequate (P = .41), with sensitivity of 42.1% and specificity of 57.1%.

CONCLUSIONS

The item concerning physical activity in the GINA questionnaire has insufficient diagnostic power to detect EIB in children and adolescents with asthma.

EFFECTS OF HAMMOCK POSITIONING ON CLINICAL PARAMETERS IN PRETERM INFANTS ADMITTED TO A NEONATAL INTENSIVE CARE UNIT: A SYSTEMATIC REVIEW

Objective:

To review the effects of the hammock positioning on clinical parameters of preterm newborn infants (PTNB) admitted to the Neonatal Intensive Care Unit (NICU).

Data sources:

This was a systematic review performed by searching the Pubmed, Lilacs, SciELO and PEDro databases. Intervention studies in English, Portuguese and Spanish that evaluated the effects of hammock positioning on clinical parameters of PTNB admitted to the NICU were selected. Three search strategies were used: 1) hammock positioning OR patient positioning AND intensive care units AND infant, newborn; 2) hammock positioning OR patient positioning AND intensive care units; 3) hammock positioning OR patient positioning AND intensive care units, neonatal. There was no restriction on the year of publication of the articles. Methodological quality was assessed by the PEDro scale.

Data synthesis:

Among 597 articles, only six were included and 139 neonates with gestational ages between 26 and 37 weeks and an average gestational weight <2240g were analyzed. Four studies included patients without any associated pathology and most of them placed the PTNB supine in hammock positioning. The duration of the intervention ranged from 15 to 180 minutes and most applied it at just one moment. There was an improvement in heart rate (HR), respiratory rate (RR) and pain (3/4 studies), as well as gains in peripheral oxygen saturation (SpO2) (2/4 studies). Only one study reported worsening of SpO2 with the intervention. The methodological quality of the studies was classified as low.

Conclusions:

Although this review suggests improvement with hammock positioning in HR, RR and pain in PTNB, the low methodological quality makes the results inconsistent.

[Diagnostic performance of the physical activity related question of the GINA questionnaire to detect exercise-induced bronchoconstriction in asthma]

INTRODUCTION

The aim of the study was to evaluate the diagnostic performance of the item concerning physical activity of the Global Initiative for Asthma (GINA) asthma control questionnaire for detection of exercise-induced bronchoconstriction (EIB) in children and adolescents.

MATERIAL AND METHODS

We divided participants (aged 6 to 18 years) with a diagnosis of asthma into two groups according to the GINA severity classification: mild/moderate asthma (MMA) and severe therapy-resistant asthma (STRA). We collected anthropometric, clinical and functional data (spirometry) and performed an EIB test. We used item 4 of the GINA questionnaire regarding exercise-induced symptoms to assess the diagnostic power of this instrument.

RESULTS

We included 40 patients (17 with MMA and 23 with STRA) with a mean age of 11.3 years and a mean FEV₁z-score of -0.33, of who 13 (32.5%) were classified as having uncontrolled asthma. Of the patients with uncontrolled asthma, 7 (53.8%) exhibited a decrease in the FEV₁ after the EIB test. We found a higher frequency of EIB in participants with FEV₁ z-score values of less than -1.0 compared to those with a z-score of -1.0 or greater (p = 0.05). There were no significant differences in the frequency of EIB based on disease severity and control. We also found no association of item 4 (GINA) with EIB. The area under the ROC curve demonstrated that the discriminative power of the GINA questionnaire for the detection of EIB is inadequate (p = 0.41), with sensitivity of 42.1% and specificity of 57.1%.

CONCLUSIONS

The physical activity related question of GINA has insufficient diagnostic power to detect EIB in children and adolescents with asthma.

Determinants of exercise capacity in children and adolescents with severe therapy-resistant asthma

OBJECTIVE

To evaluate the exercise capacity of children and adolescents with severe therapy resistant asthma (STRA) aiming to identify its main determinants.

METHODS

Cross-sectional study including individuals aged 6-18 years with a diagnosis of STRA. Clinical (age and gender), anthropometric (weight, height and body mass index) and disease control data were collected. Lung function (spirometry), cardiopulmonary exercise testing (CPET) and exercise-induced bronchoconstriction (EIB) test were performed.

RESULTS

Twenty-four patients aged 11.5 ± 2.6 years were included. The mean forced expiratory volume in one second (FEV₁) was 91.3 ± 9.2%. EIB occurred in 54.2% of patients. In CPET, the peak oxygen uptake (VO_2peak) was 34.1 ± 7.8 mL kg^-1 min^-1. A significant correlation between ventilatory reserve and FEV₁ (r = 0.57; p = 0.003) was found. Similarly, there was a significant correlation between CPET and percent of FEV₁ fall in the EIB test for both V_E/VO₂ (r = 0.47; p = 0.02) and V_E/VCO₂ (r = 0.46; p = 0.02). Patients with FEV₁<80% had lower ventilatory reserve (p = 0.009). In addition, resting heart rate correlated with VO_2peak (r=-0.40; p = 0.04), V_E/VO₂ (r = 0.46; p = 0.02) and V_E/VCO₂ (r = 0.48; p = 0.01).

CONCLUSIONS

Exercise capacity is impaired in approximately 30% of children and adolescents with STRA. The results indicate that different aspects of aerobic fitness are influenced by distinct determinants, including lung function and EIB.

EFFECTS OF PHYSICAL EXERCISE DURING HOSPITALIZATION IN CHILDREN AND ADOLESCENTS WITH CANCER: A SYSTEMATIC REVIEW

Objective:

To identify the effects of exercise programs during hospitalization on children and adolescents with cancer.

Data source:

This is a systematic review, carried out in PubMed/ Medical Literature Analysis and Retrieval System Online (MEDLINE), Latin American and Caribbean Health Sciences Literature (LILACS), Scientific Electronic Library Online (SciELO), Latin American and Caribbean Center on Health Sciences Information (BIREME), and Physiotherapy Evidence Database (PEDro). We selected studies that included children and adolescents diagnosed with cancer (solid or hematologic) and submitted to exercise protocols during hospitalization. Studies involving patients with other pathologies or with a medical contraindication for exercise were excluded. We used the following search strategy: Neoplasm OR Leukemia OR Cancer OR Tumor OR Medical Oncology AND Hospitalization OR Inpatient Care Units OR Intrahospital AND Exercise. The methodological quality of the studies was analyzed by the PEDro scale.

Data synthesis:

Among the 626 articles found, only 9 fulfilled the inclusion criteria, obtaining a regular methodological quality. The samples had 172 participants, aged 4 to 18 years. Only 6 studies presented both intervention group and control group. The intervention group received strength, aerobic, and muscle stretching exercises, and games, among others. The control group received the standard treatment. The studies varied regarding time, frequency, intensity, and type of exercise. Most studies showed an increase in muscle strength (4/5), followed by an improvement in physical fitness (2/3) and functional capacity (2/4). No adverse events were reported during the interventions. The methodological quality was considered regular.

Conclusions:

The findings suggest that. during hospitalization of children and adolescents with cancer, exercise improves muscle strength, physical fitness, and functionality.

Effect of an interdisciplinary intervention with motivational approach on exercise capacity in obese adolescents: a randomized controlled clinical trial

Objective

To evaluate the effect of an interdisciplinary intervention with a motivational approach on exercise capacity and usual physical activity levels in overweight and obese adolescents.

Methods

This is a randomized, controlled clinical trial with single blinding of subjects. Adolescents aged 15 to 18 years with overweight and obesity (body mass index ≥ 85 percentile) were included. The adolescents were randomized into two groups: interdisciplinary intervention or control − traditional approach aiming at lifestyle modifications. The initial evaluations were carried out, including the cardiopulmonary exercise test and the physical activity level measurement by using the International Physical Activity Questionnaire and a pedometer. The evaluations were performed in two moments: time zero (time of inclusion in the study) and after 3 months (end of intervention). There were 12 sessions with weekly meetings.

Results

A total of 37 participants were included, 19 in the Intervention Group. There were no significant differences in the baseline demographic, anthropometric and physical activity characteristics between groups, with mean age of 17.3±1.0 years in the Control Group, and 16.8±0.9 years in the Intervention Group (p=0.14). The motivational intervention did not cause significant differences (p>0.05) in the comparison of the variables of exercise capacity and usual physical activity (questionnaire and pedometer) between groups.

Conclusion

The intervention with a motivational approach did not alter exercise capacity and levels of usual physical activity in overweight and obese adolescents.

Clinical Trial Registry: NCT02455973 and REBEC: RBR-234nb5.

Evaluation of the exercise intensity generated by active video gaming in patients with cystic fibrosis and healthy individuals

BACKGROUND

Adherence of patients with cystic fibrosis (CF) to exercise is challenging. Here we compared the physiological responses during the use of interactive video games (VG) with the cardiopulmonary exercise test (CPET) in healthy and CF subjects.

METHODS

Cross-sectional study including CF and healthy (CON) subjects older than 6 years. Individuals were evaluated in two visits. At visit one, anthropometric measures, spirometry and CPET were performed. In the second visit, a physical activity questionnaire was applied and gas analyses performed during the use (10 min) of both Nintendo Wii (Wii Fit Plus: (1) Obstacle Course, (2) Rhythm Boxing and (3) Free Run) and Xbox One (Just Dance 2015: (1) Love Me Again, (2) Summer and (3) Happy).

RESULTS

Twenty-five CON and 30 CF patients were included. The mean FEV₁ (%) was significantly lower in the CF group compared to CON. There were no differences between groups at peak exercise (CPET) for heart rate (HR), oxygen consumption (VO₂) and minute ventilation (V_E). In the CON group, games 2 and 3 (Xbox) and game 3 (Nintendo) increased HR to values similar to the anaerobic threshold (AT), while for the CF group this occurred for games 2 (Xbox) and 3 (Nintendo). As for VO₂ and V_E, both groups obtained similar responses as compared to AT values in games 2 (Xbox) and 3 (Nintendo).

CONCLUSION

The use of VG generated a cardiorespiratory response similar to AT levels found during CPET, indicating that it may be an alternative for exercise training of CF individuals.

Modified Shuttle Test Distance Correlates With Peak Oxygen Uptake in Children and Adolescents With Severe Therapy-Resistant Asthma

Introduction

Several tests may be used to assess exercise intolerance in severe therapy-resistant asthma (STRA), including the gold standard cardiopulmonary exercise test (CPET) and the modified shuttle test (MST).

Objective

To correlate the distance achieved in the MST with peak oxygen uptake (VO₂peak) and to compare the maximal heart rate (HRmax) obtained in both tests in children and adolescents with STRA.

Methods

This is a cross-sectional study, with 19 children and adolescents with STRA. Demographic, anthropometric, clinical data, and spirometric values were collected. CPET and the MST were performed in two consecutive visits. HRmax, pulse oxygen saturation, and dyspnea were compared between tests. The distance achieved in the MST was correlated with VO₂peak.

Results

Nineteen patients with a mean age of 11.5 ± 2.5 years were included. The mean HRmax (bpm) achieved was 180.8 ± 12.10 for the MST and 187.6 ± 9.35 for CPET, whereas the mean HRmax as a percentage of predicted (HRmax%) was 90.7 ± 6.5 for the MST and 93.8 ± 4.5 for CPET. A difference of only 6 bpm was found for HRmax (p = 0.10) and of 3% for HRmax% (p = 0.06) between tests. A strong correlation was found between the MST (r = 0.79; p = 0.001) and VO₂peak measured through CPET. However, there were no correlations between the MST and both body mass index (r = -0.14; p = 0.564) and forced expiratory volume in the first second - FEV₁ (r = -0.02; p = 0.917).

Conclusion

The results demonstrate that the MST distance strongly correlates with VO₂peak, measured through CPET, and the main physiological variable responses were similar between both tests. Our results provide additional data for the use of the MST to assess exercise capacity in children and adolescents with STRA.

EXERCISE CAPACITY IN CHILDREN AND ADOLESCENTS WITH POST-INFECTIOUS BRONCHIOLITIS OBLITERANS: A SYSTEMATIC REVIEW

Objective:

To evaluate exercise capacity in children and adolescents with post-infectious bronchiolitis obliterans.

Data source:

This is a systematic review based on data from PubMed, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Scientific Electronic Library Online (SciELO), and Physiotherapy Evidence Database (PEDro). We used the following search strategy: “Exercise capacity OR Exercise Test OR Physical fitness OR Functional capacity OR Six-minute walk test OR Shuttle walk test OR Cardiopulmonary exercise test AND Bronchiolitis obliterans.” We selected studies that evaluated exercise capacity through maximal/submaximal testing in children and adolescents with post-infectious bronchiolitis obliterans, and no other associated disease. We searched articles in English, Portuguese, and Spanish, without restrictions regarding the period of publication. The methodological quality was assessed by the Agency for Healthcare Research and Quality (AHRQ) protocol.

Data synthesis:

Out of the 81 articles found, only 4 were included in this review. The studies totaled 135 participants (121 with post-infectious bronchiolitis obliterans and 14 healthy), with sample sizes between 14 and 58 subjects. All patients underwent spirometry to evaluate pulmonary function, indicating an obstructive ventilatory pattern. Among them, 3/4 had their physical performance assessed by the six-minute walk test and 2/4 by the cardiopulmonary exercise testing. These test results were compared to those of a control group (1/4) and presented as percentage of predicted and/or in meters (3/4). Lastly, 3/4 of the studies showed reduced exercise capacity in this population. The studies included were classified as having high methodological quality.

Conclusions:

Findings of the study demonstrate that children and adolescents with post-infectious bronchiolitis obliterans have reduced exercise capacity.

THE USE OF ULTRASONOGRAPHY TO EVALUATE MUSCLE THICKNESS AND SUBCUTANEOUS FAT IN CHILDREN AND ADOLESCENTS WITH CYSTIC FIBROSIS

Objective:

To compare muscle thickness and subcutaneous fat in cystic fibrosis (CF) patients and healthy controls using ultrasonography (US), and to correlate US findings with nutritional, clinical and functional variables.

Methods:

Patients aged 6 to 18 years old with a diagnosis of CF and healthy controls were included. Participants underwent anthropometric measurements, an ultrasonographic evaluation of muscle thickness and subcutaneous fat in the triceps, quadriceps, and gastrocnemius regions, and skinfold thickness measurements. Body fat percentage was estimated using skinfold measurement. Subjects with CF also underwent a pulmonary function assessment using spirometry.

Results:

We studied 39 CF patients and 45 controls. Alower body mass index was observed in CF patients (p=0.011). Body composition and muscle thickness were similar between the groups. Only calf (p=0.023) circumference and femur diameter (p<0.001) were lower in CF patients. Although there were no significant between-group differences in the comparison of US measurements of subcutaneous fat, CF patients exhibited decreased skinfold thickness in the triceps (p=0.031) and quadriceps (p=0.019). Moreover, there were weak and moderate correlations of US quadricep thickness with forced vital capacity (FVC) and lean mass, respectively. Moderate correlations of the triceps, quadriceps and gastrocnemius between US subcutaneous fat and skinfold measurements were found.

Conclusions:

Patients with CF presented a reduction in subcutaneous fat content. Muscle thickness correlated with FVC and nutritional parameters. In addition, US findings correlated positively with skinfold measurements.

Exercise Capacity Assessment by the Modified Shuttle Walk Test and its Correlation with Biochemical Parameters in Obese Children and Adolescents

OBJECTIVES

To evaluate exercise capacity of obese children and adolescents compared with normal-weight individuals and to investigate possible correlations with blood biochemical parameters.

METHODS

In this study, children and adolescents between 6 and 18 y were included and divided into control (eutrophic) and obese groups according to body mass index (BMI). Data were collected regarding demographic, anthropometric, waist circumference and exercise capacity through the Modified Shuttle Walk Test (MSWT). In the obese group, biochemical parameters in the blood (total cholesterol, HDL, LDL, triglycerides and glucose) were evaluated, and a physical activity questionnaire was applied.

RESULTS

Seventy seven participants were included; 27 in the control group and 50 obese. There was no significant difference between the two groups regarding sample characteristics, except for body weight, BMI and waist circumference. Most obese children presented results of biochemical tests within the desirable limit, though none were considered active. There was a significant exercise capacity reduction (p < 0.001) in the obese group compared to control subjects. Positive correlations were identified for the MSWT with age and height, and a negative correlation with BMI. However, there were no correlations with the biochemical parameters analyzed.

CONCLUSIONS

Obese children and adolescents have reduced exercise capacity when compared to normal individuals. The MSWT performance seems to have a negative association with BMI, but is not correlated with blood biochemical parameters.

Predictive maximal heart rate equations in child and adolescent athletes: a systematic review

Abstract Introduction: The maximal heart rate (HRmax) is considered the highest value of HR achieved during a physical effort close to exhaustion. Objective: To evaluate the applicability of the predictive HRmax equations during exercise tests in child and adolescent athletes through a systematic review. Methods: It is a systematic review, through Scopus, Pubmed, Lilacs, Scielo and PEDro. The included studies compared the measured and estimated HRmax predictive equations during exercise tests in child and adolescent athletes. The following search strategy was used: “Exercise test OR Exercise testing OR Cardiopulmonary exercise test OR Cardiopulmonary exercise testing OR Peak oxygen uptake OR Maximal oxygen consumption OR Exercise capacity OR Heart rate OR Heart rate OR Pulse rate OR Pulse rates OR Heart rate control OR Cardiac chronotropic OR Predictive value test AND Predictive equations”. Results: From a total of 1,664 articles, only 4 were included. All compared the measured HRmax values with those estimated by the “220 - age” equation; 3 used the formula “208 - (0.7 x age)”, and only 1 used the “223 - (1.44 x age)” equation. Although all of them stated that the “220 - age” equation overestimates HRmax, the formula “208 - (0.7 x age”) underestimated (2 articles) and overestimated (1 study) the measured results, while the equation “213 - (1.44 x age) was also not adequate. Conclusion: The use of predictive HRmax equations for child and adolescent athletes does not seem to be recommended. The use of cohort points for these estimates is carefully recommended.

MAXIMUM HEART RATE MEASURED VERSUS ESTIMATED BY DIFFERENT EQUATIONS DURING THE CARDIOPULMONARY EXERCISE TEST IN OBESE ADOLESCENTS

OBJECTIVE

To compare the values of measured maximum heart rate (HRmax) and maximum heart rate estimated by different equations during the cardiopulmonary exercise test (CPET) in obese adolescents.

METHODS

This is a cross-sectional study. Adolescents aged between 15 and 18 years old, with obesity (BMI Z-score>2.0) were included. Demographic and anthropometric data were collected, followed by CPET, recording HRmax. The highest heart rate reached at peak exercise was considered as HRmax. The comparison between measured and estimated HRmax values was performed using four previous equations. Descriptive statistics and the ANOVA test (Bonferroni post-test) were used.

RESULTS

Fifty-nine obese adolescents were included, 44% of them male. The mean age was 16.8±1.2 years old and the BMI (Z-score) was 3.0±0.7. At peak exercise, the mean HRmax (bpm) was 190.0±9.2, the respiratory coefficient was 1.2±0.1, and the VO2max (mL/kg/min) was 26.9±4.5. When comparing the measured values of HRmax with those estimated by the different formulas, the equations "220-age", "208-0.7 x age" and "207-0.7 x age" were shown to overestimate (p<0.001) the measured HRmax results in obese adolescents. Only the "200-0.48 x age" equation presented similar results (p=0.103) with the values measured in the CPET.

CONCLUSIONS

The findings of the present study demonstrate that the equation "200-0.48 x age" seems to be more adequate to estimate HRmax in obese adolescents.

Growth, lung function, and physical activity in schoolchildren who were very-low-birth-weight preterm infants

Objective:

To compare somatic growth, lung function, and level of physical activity in schoolchildren who had been very-low-birth-weight preterm infants (VLBWPIs) or normal-birth-weight full-term infants.

Methods:

We recruited two groups of schoolchildren between 8 and 11 years of age residing in the study catchment area: those who had been VLBWPIs (birth weight < 1,500 g); and those who had been normal-birth-weight full-term infants (controls, birth weight ≥ 2,500 g). Anthropometric and spirometric data were collected from the schoolchildren, who also completed a questionnaire regarding their physical activity. In addition, data regarding the perinatal and neonatal period were collected from the medical records of the VLBWPIs.

Results:

Of the 93 schoolchildren screened, 48 and 45 were in the VLBWPI and control groups, respectively. No significant differences were found between the groups regarding anthropometric characteristics, nutritional status, or pulmonary function. No associations were found between perinatal/neonatal variables and lung function parameters in the VLBWPI group. Although the difference was not significant, the level of physical activity was slightly higher in the VLBWPI group than in the control group.

Conclusions:

Among the schoolchildren evaluated here, neither growth nor lung function appear to have been affected by prematurity birth weight, or level of physical activity.

Reference Values for Inspiratory Muscle Endurance in Healthy Children and Adolescents

Aims

To generate reference values for two inspiratory muscle endurance (IME) protocols in healthy children and adolescents.

Materials and methods

This is an observational, cross-sectional study, in healthy children and adolescents from 4 to 18 years of age. Weight, height, maximal inspiratory pressure (MIP) and IME were measured using two protocols. A fixed load of 30% of MIP with a 10% increment every 2 minutes was used in the incremental threshold loading protocol. As for the maximal loading protocol, a fixed load of 70% of MIP was used and the time limit (Tlim) achieved until fatigue was measured.

Results

A total of 462 participants were included, 281 corresponding to the incremental loading protocol and 181 to maximal loading. There were moderate and positive correlations between IME and age, MIP, weight and height in the incremental threshold loading. However, the regression model demonstrated that MIP and age were the best variables to predict the IME. Otherwise, weak and positive correlations with age, weight and height were found in the maximal loading. Only age and height influenced endurance in the regression model. The predictive power (r²) of the incremental threshold loading protocol was 0.65, while the maximal loading was 0.15. The reproducibility measured by the intraclass correlation coefficient (ICC) was higher in the incremental loading (0.96) compared to the maximal loading test (0.69).

Conclusion

IME in healthy children and adolescents can be explained by age, height and MIP. The incremental threshold loading protocol showed more reliable results and should be the model of choice to evaluate IME in the pediatric age group.

Asthma and Obesity in Children Are Independently Associated with Airway Dysanapsis

BACKGROUND

An increase in the prevalence of overweight and asthma has been observed. Both conditions affect negatively lung function in adults and children. The aim of this study was to analyze the effect of overweight and asthma on lung function in children.

METHODS

We designed a case-control study of healthy and asthmatic subjects nested within an epidemiological asthma prevalence study in children between 8 and 16 years of age. The effect of asthma and overweight on lung function was assessed by impulse oscillometry and spirometry obtained at baseline and 10-15 min after salbutamol.

RESULTS

188 children were recruited, 114 (61%) were asthmatics and 72 (38%) were overweight or obese. Children with asthma and overweight had a higher FVC (+1.16 z scores, p < 0.001) and higher FEV₁ (+0.79 z scores, p = 0.004) and lower FEV₁/FVC (-0.54 z scores, p = 0.008) when compared to healthy controls. Compared to normal weight asthmatics, the overweight had higher FVC (+0.78 z scores, p = 0.005) and lower FEV₁/FVC (-0.50 z scores, p = 0.007). In the multivariate analysis, overweight was associated with an increase of 0.71 and 0.44 z scores in FVC and FEV₁, respectively, and a reduction in FEV₁/FVC by 0.40 z scores (p < 0.01 for all). Overweight had no effect on maximal flows and airway resistance at baseline, and this was not modified by inhalation of a bronchodilator. Asthma was also associated with higher post-BD FVC (0.45 z scores, p = 0.012) and FEV₁ (0.35 z scores, p = 0.034) but not with FEV₁/FVC and FEF_25-75%. Two-way analysis of variance did not detect any interaction between asthma and overweight on lung function variables before or after bronchodilator.

CONCLUSION

Our results suggest that asthma and overweight are independently associated with airway dysanaptic growth in children which can be further scrutinized using impulse oscillometry. Overweight contributed more to the reduction in FEV₁/FVC than asthma in children without increasing airway resistance. Spirometry specificity and sensitivity for obstructive diseases may be reduced in populations with high prevalence of overweight. Adding impedance oscillometry to spirometry improves our understanding of the ventilatory abnormalities in overweight children.

Inspiratory muscle training in pediatrics: main indications and technical characteristics of the protocols

Abstract Introduction: Inspiratory muscle training (IMT) is a resource widely used in pediatrics. However, there is great variability in relation to the characteristics of the protocols used. Objective: To identify the main clinical conditions and IMT protocols used in the pediatric age group. Methods: Integrative review of the literature by searching on Pubmed, Scielo, PEDro and EMBASE databases using the following strategy: threshold OR inspiratory muscle training OR muscle endurance OR muscle resistance OR endurance training OR maximal inspiratory pressure AND respiratory muscle. We have selected clinical trials that performed IMT in children and adolescents (0 to 18 years old), with a clinical diagnosis, and published in English, Portuguese and Spanish. Results: 17 studies were included. From these, 11 underwent IMT in patients with some neuromuscular disorder, being Duchenne Muscular Dystrophy the most common. The selected articles included a total sample of 327 participants. As for the characteristics of the protocols, 7 performed strength training, 5 endurance and 5 strength and endurance. The training load ranged from 30 to 80% of maximal inspiratory pressure. Moreover, 8 studies performed IMT twice daily and the session duration and the training period varied between 10 and 30 minutes, and from 3 weeks to 24 months, respectively. Conclusion: The IMT was used more frequently in patients with some neuromuscular disorder. Although there is no consensus as to the characteristics of the protocols, the choice of the load should take into account the purpose of IMT and the disease severity.

Variation in lung function is associated with worse clinical outcomes in cystic fibrosis

OBJECTIVE

To determine whether the variation in lung function over one year is associated with worse clinical outcomes, as well as with a decline in lung function in the following years, in patients with cystic fibrosis (CF).

METHODS

This was a retrospective study involving CF patients (4-19 years of age), evaluated over a three-year period. We evaluated demographic characteristics, chronic Pseudomonas aeruginosa infection, antibiotic use, hospitalization, six-minute walk distance (6MWD), and lung function. The inclusion criterion was having undergone pulmonary function testing at least three times in the first year and at least once in each of the next two years.

RESULTS

We evaluated 35 CF patients. The variation in FEV1 in the first year (ΔFEV1) was greater among those who, in the third year, showed reduced FEV1, had a below-average 6MWD, or were hospitalized than among those with normal FEV1, normal 6MWD, or no hospital admissions, in that same year (p < 0.05), although no such difference was found for antibiotic use in the third year. Subjects showing a ΔFEV1 ≥ 10% also showed a greater decline in FEV1 over the two subsequent years (p = 0.04). The ΔFEV1 also showed an inverse correlation with absolute FEV1 in the third year (r = -0.340, p = 0.04) and with the rate of FEV1 decline (r = -0.52, p = 0.001). Linear regression identified ΔFEV1 as a predictor of FEV1 decline (coefficient of determination, 0.27).

CONCLUSIONS

Significant variation in lung function over one year seems to be associated with a higher subsequent rate of FEV1 decline and worse clinical outcomes in CF patients. Short-term ΔFEV1 might prove useful as a predictor of CF progression in clinical practice.

Frequência de sucesso de pré-escolares e escolares com e sem sintomas respiratórios nos testes de função pulmonar

RESUMO O objetivo deste estudo foi avaliar a frequência de sucesso de pré-escolares e escolares com e sem sintomas respiratórios nos testes de função pulmonar. Foram incluídas crianças e adolescentes com idade entre quatro e 12 anos com e sem sintomas respiratórios, baseados no questionário de doenças respiratórias. Os participantes foram recrutados em duas escolas e classificados, de acordo com sua faixa etária, em pré-escolares (4-6 anos) e escolares (7-12 anos). Foram coletados dados demográficos e antropométricos, além das variáveis dos testes de manovacuometria (PIMAX e PEMAX) e de espirometria (VEF1, CVF, VEF1/CVF e FEF25-75%). Os testes de função pulmonar foram considerados bem-sucedidos quando os participantes preenchiam os critérios de aceitabilidade e reprodutibilidade das diretrizes nacionais e internacionais. Para fins estatísticos, utilizou-se o teste de qui-quadrado e correlação de Pearson. Foram incluídos 148 participantes, com média de idade de 8,1±1,7 anos, sendo 51,4% do sexo feminino e 85,1% saudáveis. A taxa de sucesso no teste de manovacuometria e de espirometria foi de 91,9% e 91,2%, respectivamente. Houve uma taxa de sucesso significativamente menor no grupo de pré-escolares em comparação aos escolares, tanto para o teste de manovacuometria (p=0,044) como para o exame espirométrico (p=0,015). As correlações entre as variáveis do teste de manovacuometria e do exame espirométrico mostraram-se positivas e moderadas entre a PIMAX e a CVF, e a PEMAX e o VEF1 e FEF25-75%. Os achados demonstram uma frequência de sucesso significativamente menor no grupo etário pré-escolar em comparação com os sujeitos escolares em ambos os testes de função pulmonar avaliados.

Inspiratory muscle function in asthmatic and healthy subjects: influence of age, nutrition and physical activity

OBJECTIVE

To compare inspiratory muscle function (strength and endurance) between asthmatics and healthy controls, and the influence of age, nutritional status and physical activity on them.

METHODS

This is a cross-sectional study. Asthmatic and healthy subjects, aged 6 to 18 years old, recruited from two public schools in Southern Brazil were included in the study. Asthmatic subjects were selected using the criteria presented by the International Study on Asthma and Allergies in Children and control subjects based on the absence of respiratory symptoms. Anthropometric data was measured, body mass index calculated and subjects classified as normal weight, overweight or obese. Physical activity levels, maximum inspiratory pressure (MIP) and inspiratory muscle endurance (IME) were also evaluated.

RESULTS

A total of 314 participants were included, separated into control group (181) and asthmatics (133), with a total mean age of 11 years. When both groups were compared, there were no significant differences in both MIP and IME. However, when groups were analyzed subdivided in children and adolescents, IME was significantly reduced (p = 0.003) in asthmatic adolescents. Indeed, when groups were also stratified considering the nutritional status, IME showed a reduction in asthmatic adolescents with overweight (p = 0.042) and obesity (p = 0.041) when compared to healthy controls. No effects of physical activity levels between groups were found.

CONCLUSIONS

Results demonstrate a reduction in the IME in asthmatic adolescents with overweight and obesity, indicating an association between asthma, nutritional status and respiratory muscle function.

Effects of obesity on lung volume and capacity in children and adolescents: a systematic review

OBJECTIVE

To assess the effects of obesity on lung volume and capacity in children and adolescents.

DATA SOURCE

This is a systematic review, carried out in Pubmed, Lilacs, Scielo and PEDro databases, using the following Keywords: Plethysmography; Whole Body OR Lung Volume Measurements OR Total Lung Capacity OR Functional Residual Capacity OR Residual Volume AND Obesity. Observational studies or clinical trials that assessed the effects of obesity on lung volume and capacity in children and adolescents (0-18 years) without any other associated disease; in English; Portuguese and Spanish languages were selected. Methodological quality was assessed by the Agency for Healthcare Research and Quality.

DATA SYNTHESIS

Of the 1,030 articles, only four were included in the review. The studies amounted to 548 participants, predominantly males, with sample size ranging from 45 to 327 individuals. 100% of the studies evaluated nutritional status through BMI (z-score) and 50.0% reported the data on abdominal circumference. All demonstrated that obesity causes negative effects on lung volume and capacity, causing a reduction mainly in functional residual capacity in 75.0% of the studies; in the expiratory reserve volume in 50.0% and in the residual volume in 25.0%. The methodological quality ranged from moderate to high, with 75.0% of the studies classified as having high methodological quality.

CONCLUSIONS

Obesity causes deleterious effects on lung volume and capacity in children and adolescents, mainly by reducing functional residual capacity, expiratory reserve volume and residual volume.

Effects of obesity on lung volume and capacity in children and adolescents: a systematic review

OBJECTIVE

To assess the effects of obesity on lung volume and capacity in children and adolescents.

DATA SOURCE

This is a systematic review, carried out in Pubmed, Lilacs, Scielo and PEDro databases, using the following Keywords: Plethysmography; Whole Body OR Lung Volume Measurements OR Total Lung Capacity OR Functional Residual Capacity OR Residual Volume AND Obesity. Observational studies or clinical trials that assessed the effects of obesity on lung volume and capacity in children and adolescents (0-18 years) without any other associated disease; in English; Portuguese and Spanish languages were selected. Methodological quality was assessed by the Agency for Healthcare Research and Quality.

DATA SYNTHESIS

Of the 1,030 articles, only four were included in the review. The studies amounted to 548 participants, predominantly males, with sample size ranging from 45 to 327 individuals. 100% of the studies evaluated nutritional status through BMI (z-score) and 50.0% reported the data on abdominal circumference. All demonstrated that obesity causes negative effects on lung volume and capacity, causing a reduction mainly in functional residual capacity in 75.0% of the studies; in the expiratory reserve volume in 50.0% and in the residual volume in 25.0%. The methodological quality ranged from moderate to high, with 75.0% of the studies classified as having high methodological quality.

CONCLUSIONS

Obesity causes deleterious effects on lung volume and capacity in children and adolescents, mainly by reducing functional residual capacity, expiratory reserve volume and residual volume.

Clinical characteristics of children and adolescents with severe therapy-resistant asthma in Brazil

OBJECTIVE

To describe the clinical characteristics, lung function, radiological findings, and the inflammatory cell profile in induced sputum in children and adolescents with severe therapy-resistant asthma (STRA) treated at a referral center in southern Brazil.

METHODS

We retrospectively analyzed children and adolescents (3-18 years of age) with uncontrolled STRA treated with high-dose inhaled corticosteroids and long-acting β2 agonists. We prospectively collected data on disease control, lung function, skin test reactivity to allergens, the inflammatory cell profile in induced sputum, chest CT findings, and esophageal pH monitoring results.

RESULTS

We analyzed 21 patients (mean age, 9.2 ± 2.98 years). Of those, 18 (86%) were atopic. Most had uncontrolled asthma and near-normal baseline lung function. In 4 and 7, induced sputum was found to be eosinophilic and neutrophilic, respectively; the inflammatory cell profile in induced sputum having changed in 67% of those in whom induced sputum analysis was repeated. Of the 8 patients receiving treatment with omalizumab (an anti-IgE antibody), 7 (87.5%) showed significant improvement in quality of life, as well as significant reductions in the numbers of exacerbations and hospitalizations.

CONCLUSIONS

Children with STRA present with near-normal lung function and a variable airway inflammatory pattern during clinical follow-up, showing a significant clinical response to omalizumab. In children, STRA differs from that seen in adults, further studies being required in order to gain a better understanding of the disease mechanisms.

Equações internacionais superestimam a força muscular ventilatória em crianças e adolescentes com fibrose cística

O objetivo deste estudo foi comparar os resultados da normalização dos dados de força muscular ventilatória utilizando-se três equações de referência internacionais e uma nacional em crianças e adolescentes com fibrose cística (FC). Estudo retrospectivo, no qual foram incluídos pacientes com FC, idade entre 8 e 12 anos e acompanhamento ambulatorial regular. Foram coletados dados demográficos e variáveis antropométricas. Todos os pacientes incluídos deveriam ter realizado teste de força muscular ventilatória e espirometria nos últimos 12 meses. A normalização dos resultados foi realizada utilizando-se as variáveis preditoras requeridas em cada equação estudada. Os dados foram comparados utilizando-se uma ANOVA de uma via. Foram incluídos 24 pacientes, 62,5% masculinos, média de idade 10,5±1,53 anos, estatura 138,0±0,08 cm, massa corporal 34,6±9,07 kg, VEF1 93,29±29,02% e CVF 103,78±26,12%. As pressões (cmH2O) inspiratória (PIMAX) e expiratória (PEMAX) máximas encontradas foram 92,1±22,8 e 98,9±24,5, respectivamente. Após a normalização pelas diferentes equações, demonstrou-se que as internacionais tendem a superestimar os achados para a nossa população. A equação nacional apresentou valores médios previstos significativamente (p<0,05) menores para PIMAX e PEMAX em comparação com as equações internacionais, sendo que estas classificariam a PIMAX como acima do normal (>100%) em 91,6, 79,1, e 75,0% dos sujeitos e a PEMAX em 66,6, 87,5 e 50%, enquanto a equação nacional estimaria apenas 50,0 e 37,5% dos indivíduos, respectivamente. A normalização dos resultados de força muscular ventilatória em crianças e adolescentes entre 8 e 12 anos com FC utilizando-se equações internacionais superestimam os valores das pressões respiratórias máximas.

Ventilatory muscle strength in cystic fibrosis patients: a literature review

The ventilatory mechanic changes that occur in cystic fibrosis (CF) patients may lead to alterations in the respiratory muscle strength levels. However, the findings regarding the strength profile in these patients are still contradictory.

OBJECTIVE

To evaluate, trough a literature review, the respiratory muscle strength behavior in CF patients. We have performed a search in Medline/Pubmed, Scielo, IBECS and LILACS databases selecting observational cross-sectional, prospective or retrospective studies, as well as randomized clinical trials, published between 1981 and 2011, using the following terms: cystic fibrosis, respiratory muscle strength, inspiratory maximal pressure and muscle training. The majority of the studies 71.24% have shown normal or above normal respiratory muscle strength, whilst 28.57% demonstrated reduced or near-normal values. Most of these findings were attributed to an increased work of breathing as a result of airway obstruction and chronic persistent cough. Taken together, the analyses of selected studies have showed conflicting findings regarding respiratory muscle strength behavior in these patients. However, most of the studies seem to indicate that CF patients presented maximum respiratory pressures normal or above predicted values.