Validation of a web-based version of the asthma control test and childhood asthma control test.

RATIONALE: Recent guidelines focus on adjusting asthma treatment to the level of asthma control. The availability of a web-based asthma control questionnaire offers the possibility to assess asthma control without the need of outpatient clinic visits. The aim of this study was to evaluate the agreement between web-based and paper-based versions of the Asthma Control Test (ACT) and Childhood Asthma Control Test (C-ACT), short-term reproducibility and satisfaction with both versions. METHODS: One hundred seventy-three children with stable asthma and a normal lung function were randomized to fill in a web-based or paper-based version of the C-ACT (4-11 years) or ACT (12-18 years). According to a cross-over design, they completed the opposite version after 1 week. Reproducibility was evaluated by repeating the 2nd version (web- or paper-based) 7 days later. RESULTS: Eighty-eight children filled in the C-ACT, 68 children filled in the ACT. Intraclass Correlation Coefficient (ICC) for web-based versus paper-based C-ACT was 0.81 (95% confidence interval [95% CI] 0.72-0.87). For ACT this was 0.84 (95% CI 0.76-0.90). For web-based and paper-based C-ACT the reproducibility ICC was 0.82 (95% CI 0.67-0.90) and 0.75 (95% CI 0.59-0.85), respectively. The reproducibility ICC of the ACT for web- and paper-based versions was 0.93 (95% CI 0.87-0.97) and 0.77 (95% CI 0.59-0.88), respectively. Eighty-six percent of patients preferred the web-based version. CONCLUSION: The web-based version of the C-ACT and ACT is reproducible and comparable with the paper-based version in assessing asthma control. Most children and their parents prefer the web-based version.

Comparing Global Initiative for Asthma (GINA) criteria with the Childhood Asthma Control Test (C-ACT) and Asthma Control Test (ACT).

Several tools are useful in detecting uncontrolled asthma in children. The aim of this study was to compare Global Initiative for Asthma (GINA) guidelines with the Childhood Asthma Control Test (C-ACT) and the Asthma Control Test (ACT) in detecting uncontrolled asthma in children. 145 children with asthma filled in a web-based daily diary card for 4 weeks on symptoms, use of rescue medication and limitations of activities, followed by either the C-ACT or ACT. For predicting uncontrolled asthma, score cut-off points of 19 were used for C-ACT and ACT. According to GINA guidelines, asthma was uncontrolled in 71 (51%) children and completely controlled in 19 (14%) children. The area under the curve in the receiver operating characteristic curves for C-ACT and ACT versus GINA guidelines were 0.89 and 0.92, respectively. Cut-off points of 19 for C-ACT and ACT resulted in a sensitivity of 33% and 66% in predicting uncontrolled asthma, respectively. C-ACT and ACT correlate well with GINA criteria in predicting uncontrolled asthma, but commonly used cut-off points for C-ACT and ACT seem to underestimate the proportion of children with uncontrolled asthma as defined by GINA.

Participation in daily life of children with asthma.

Asthma can have a negative effect on psychological and social well-being in childhood. Sports participation, school attendance, and quality of life are important issues for children with asthma and their parents. However, a structural evaluation of these factors is not always incorporated in the routine medical approach of children with asthma. Moreover, goals in asthma treatment, such as minimal symptoms and normal activity levels, are achieved in a minority of children. This review describes determinants that are important for the well-being of children with asthma and their parents. Besides the control of symptoms, factors such as sports participation, socializing in peer groups, school attendance, and quality of life must be considered. These issues are relevant when evaluating the management of children and adolescents with asthma. A multidisciplinary evaluation by a pediatrician, school nurse, gym teacher, and psychologist might contribute to an important decrease in the impact of asthma on daily life.

[Guideline 'Treating asthma in children' for pediatric pulmonologists (2nd revised edition). II. Medical treatment]. / Richtlijn 'Astmabehandeling bij kinderen' van kinderlongartsen (2e herziening). II. Medicamenteuze behandeling.

The second revision of the guidelines for the treatment of asthma in children is largely based on the evidence of comparative studies. Short-acting beta 2-sympathicomimetics are the medication of choice for acute exacerbations and should therefore be prescribed to each patient. Inhaled corticosteroids (ICS) are the medication of choice for maintenance treatment. Starting with a high dose of ICS which is then reduced to a lower but effective level on the basis of the complaints (step-down approach) is no longer recommended, as this strategy is not more effective than a constant dosage schedule. If asthmatic symptoms persist despite ICS maintenance treatment then 3 therapeutic options are available in the following order: doubling the ICS dose, the addition of a long-acting beta 2-sympathicomimetic, and the addition of a leukotriene receptor antagonist.

Applicability of interrupter resistance measurements using the MicroRint in daily practice.

This study was performed to evaluate the applicability of a simple device (MicroRint) for measuring airway resistance, to derive normal values and to compare values with maximal expiratory flow volume (MEFV) parameters in asthmatic and healthy children. Repetitive R(int) measurements were performed in 125 healthy children and 107 asthmatic children (age range 0.8-16.8 years). In 42 asthmatic patients R(int) and MEFV values were compared and in 29 asthmatic children bronchodilation testing was performed. Successful R(int) measurements were possible in 91% of the children. The mean coefficient of variation of repeated measurements was 7.1 (+/-6.1)%. R(int) values of healthy children showed a significant curvilinear correlation with age (r=-0.80, P < 0.001) and height (r=-0.81, P < 0.001). In asthmatic and healthy children R(int) values were comparable. A significant inverse correlation was found between R(int) and MEFV values (for FEV1 and R(int) r=-0.80, P < 0.001). After bronchodilation there was a significant increase in FEV1 and decrease in R(int), but changes between the two parameters did not correlate. In conclusion, the interrupter technique is feasible and repeatable in children and has a significant correlation with other parameters of airway caliber. Baseline values do not discriminate healthy from asthmatic children.

Children with mild asthma: do they benefit from inhaled corticosteroids?

In children with mild asthma, who show hardly any abnormalities in pulmonary function, objective measurement of the effect of inhaled corticosteroids is difficult. The short term effect of fluticasone propionate (FP) in these children was evaluated, using both subjective and objective parameters. A total of 68 children (5-10 yrs old) were randomly assigned to either FP 250 microg or placebo twice daily as metered-dose inhaler via spacer during 12 weeks. Symptom scores, use of rescue medication, wheezing, parent global evaluation and pulmonary function tests including forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) and bronchial responsiveness (provocation dose of methacholine causing a 20% fall in FEV1 (PD20)) were evaluated. FP-treated versus placebo-treated children showed significant changes in percentage symptom-free days, use of beta2-mimetics, morning and evening PEF, FEV1 % pred and wheezing. No significant improvements were found in parent global evaluation, absolute values of FEV1 nor PD20. These findings show that inhaled corticosteroids are effective in children with mild asthma. This effect can be assessed by both objective and subjective parameters. Early start of inhaled corticosteroids should be considered even when pulmonary function is normal.

Lung function abnormalities in children with type I diabetes.

Recent developments in intrabronchial administration of insulin raise lung function in patients with type I diabetes as important issue. Several studies in adults report abnormalities of lung function of these patients. The aim of this study was to investigate lung function in children with type I diabetes. Twenty-seven children with type I diabetes performed measurement of airway obstruction (forced flow-volume curves), lung volumes and airway resistance (bodyplethysmography) and of pulmonary carbon monoxide diffusion capacity Mean age (+/- SD) of the children was 12.8 +/- 5 years. Mean time between the detection of type I diabetes and the lung function tests was 5.5 years with a variation from I to 17 years. The total airway resistance (Raw) was significantly higher compared to the reference values (P < 0.001). The other lung function parameters were not significantly different from reference values (P > 0.05). In this relatively small study no relationship between lung function abnormalities and age, the duration of disease or level of HbA1c was observed. Our data show that increase of airway resistance do occur in children withtype I diabetes. Progressive abnormalities in lung function might interfere with the promising results of treatment with intrabronchial administration of insulin.

Forced expiratory manoeuvres in children: do they meet ATS and ERS criteria for spirometry?

The aim of this study was to evaluate the applicability of American Thoracic Society and European Respiratory Society criteria for spirometry in children. Maximal expiratory flow/volume (MEFV) measurements from 446 school-age children, experienced in performing MEFV manoeuvres, were studied and acceptability (start-of-test (backward extrapolated volume as a percentage of forced vital capacity (FVC) ([Vbc%FVC) or as an absolute value (Vbe), end-of-test (forced expiratory time (FET)) and reproducibility criteria (absolute and percentage difference between best and second-best FVC and forced expiratory volume in one second (FEV1) (deltaFVC, deltaFVC %, deltaFEV1 and deltaFEV1 %)) were applied to these manoeuvres. The Vbe%FVC criterion was met by 91.5%, the Vbe <0.15 L criterion by 94.8% and the Vbe <0.10 L by 60.1% of children. Vbe <0.15 L appeared to be a more useful parameter than Vbe%FVC. The FET criterion was met by only 15.3% of children. deltaFVC <0.2 L and deltaFEV1 <0.2 L were met by 97.1% and 98.4%, and deltaFVC <0.1 L and deltaFEV1 <0.1 L by 79.8% and 84.3% of the children, respectively. These criteria appeared to be less useful compared to percentage criteria (deltaFVC % and deltaFEV1 %). Even experienced children did not meet all international criteria for spirometry. However, most of their MEFV curves are useful for interpretation. Based on the performance of these children, a re-evaluation of criteria for maximal expiratory flow/volume measurements in children is proposed.

Central airways behave more stiffly during forced expiration in patients with asthma.

Chronic inflammation and extracellular remodeling of the airway wall characterize asthma. The purpose of this study was to examine whether these features cause a change in airway mechanical properties. We examined 14 healthy and 10 young adults with long-lasting asthma, the latter treated with inhaled bronchodilators and corticosteroids. To obtain area-versus-transmural pressure (A-Ptm) curves during forced expiration (Pedersen, O. F., et al. J. Appl. Physiol. 1982;52:357-369), we used an esophageal balloon and a Pitot static probe positioned at five locations between the right lower lobe and midtrachea. Cross-sectional area (A), airway compliance (Caw = dA/dPtm), and specific airway compliance (sCaw = Caw/A) were obtained from the A-Ptm curves. Results showed that: (1) A was larger in males than in females; (2) Caw and sCaw decreased with a more downstream position; and (3) Caw and sCaw were significantly lower in the patients with asthma, with the differences between the asthmatic patients and the healthy subjects becoming smaller toward the trachea. The lower Caw and sCaw in the patients with long-lasting asthma support the concept that chronic inflammation and remodeling of the airway wall may result in stiffer dynamic elastic properties of the asthmatic airway.

Outpatient exercise training in children with cystic fibrosis: physiological effects, perceived competence, and acceptability.

Exercise training is currently advocated as part of the treatment of patients with cystic fibrosis (CF). However, data are few that document physiologic benefits or changes in patients' perceptions of long-term training programs in children with CF. The aim of this study was to investigate the effects and acceptability of a home cycling program in children with CF. Fourteen patients (9 boys, 5 girls) with CF, mean (SD) age 14.1 (2.0) years, with mild to moderate impairment of lung function (forced expiratory volume in 1 s, mean (SD) 58.3 (16.3)% of predicted) were studied for 1 year. The first half of the study year was used to obtain baseline values at 0 and 6 months. During the second half of the year, a cycle program was carried out 5 times a week, for 20 min each day at a level of work that resulted in a heart rate of 140-160 beats/min. Once a week the cycle program was supervised by a physiotherapist. Measurements were repeated at 12 months. Effects of the exercise program were measured in terms of lung function, nutritional status, growth, muscle strength, exercise performance, perceived competence, and attitude towards the training program. Differences between the changes during the 6-month training period as compared to the 6-month control period were analyzed by multivariate statistics and nonparametric tests. Statistically significant differences (P < 0.05) between the two periods were found with respect to muscle strength of knee extensors and ankle dorsiflexors, and with respect to maximal oxygen consumption per kg body weight as well as per kg fat free mass. All changes were positive. No adverse effects were found. Perceived competence showed significant positive changes in feelings about physical appearance, general self-worth, and Total Perceived Competence Score. Scores concerning perceived acceptability of the program were significantly lower at the end of the training period; however, patients reported that they did want to continue with other sorts of training. We conclude that an exercise training program in the home can produce beneficial effects on oxygen consumption, muscle force, and perceived competence in children with CF. However, acceptability of the program was low, suggesting that long-term adherence would be poor, and hence, other sorts of training need to be identified.

Handling of a spacer (Babyhaler) for inhalation therapy in 0- to 3-year-old children.

The handling of the Babyhaler spacer for inhalation therapy in children 0-3 years old with asthma was tested and the perceptions of the investigators with the instruction of this device to the parents was investigated. It was an open, multicenter study of 182 patients with a treatment period of 2 weeks and a 2-week follow-up period. Thirty pediatricians in Dutch local and university hospitals participated. Using a standardized instruction, the purpose and the application of the Babyhaler were explained and demonstrated, and parents were asked to use the Babyhaler on their own child. The quality of the demonstration was scored and, if necessary, additional instruction was given. In the following treatment period of 2 weeks record card was completed; the convenience score of the Babyhaler and the symptom score were recorded. At the following evaluation visit the handling of the Babyhaler by the parents was re-evaluated. Eighty-nine percent of the parents could use the Babyhaler correctly after one instruction. The instructions of the Babyhaler were considered to be easy in 83% of the cases by the parents and the investigators. During the treatment period the handling score (6 = impossible to use, 1 = very easy) improved from 2.4 to 1.7. At the evaluation visit the correct use was similar to the result at the instruction visit (87%). No differences were found in the ease of handling between the three age groups (0-1, 1-2, and 2-3 years). The application of inhalation therapy via the Babyhaler was favored by 92% of the parents as compared to the former treatment method. We demonstrated that the Babyhaler is easy to use by the parents and that the instruction of the device by practitioners is also perceived as easy.

Maximal work capacity in relation to nutritional status in children with cystic fibrosis.

In children with cystic fibrosis, objective parameters of exercise tolerance are needed which are easy to measure in nonspecialized centres. We investigated maximal workload (W'max) in children with cystic fibrosis in relation to body weight and fat-free mass, and compared this with results for maximal oxygen consumption (V'O2,max). Fourteen patients with cystic fibrosis performed an incremental maximal exercise test on a bicycle ergometer. W'max, V'O2,max, body weight and fat-free mass were measured. W'max and V'O2,max were significantly correlated (r = 0.91; p < 0.001). Using standard deviation scores in relation to reference values, W'max and V'O2,max per kilogram body weight were significantly higher than uncorrected W'max and V'O2,max (mean difference (95% CI) 0.63 (0.24-1.01) and 0.91 (0.32-1.49) SD units, respectively). There was no such difference after correction for fat-free mass. Standardized V'O2,max was significantly higher than standardized W'max (mean difference (95% CI): 1.59 (1.14-2.04)), also after correction for body weight and fat-free mass. In children with mild-to-moderate cystic fibrosis, maximal workload per kilogram fat-free mass, but not per kilogram body weight, is a useful parameter to correct for diminished nutritional status. In these patients, maximal workload is consistently lower than maximal oxygen consumption. Taking into account this difference, maximal workload and maximal workload per kilogram fat-free mass can be used for follow-up of paediatric patients with cystic fibrosis in nonspecialized settings.

Correlates of disablement in systemic onset juvenile chronic arthritis. A cross sectional study.

The impact of systemic onset JCA on functional outcome was studied in a multidimensional construct. Twenty-one patients were subjected to auxologic evaluation, a laboratory check, pulmonary and cardiac function tests, radiographic evaluation, joint count on tenderness, swelling and function, ADL, health assessment (CHAQ), and psychosocial evaluation. Six of 21 patients had active systemic disease. Restrictive pulmonary function was found in 8/17 patients, 1/21 had pericarditis. Joint impairment was moderate. Functional limitations were mild. Self-esteem was positive. Parental report on functional limitation correlated significantly with joint impairment. Performance of daily activities correlated strongly with perceived competence. Active inflammatory disease did not correlate with joint impairment and functional limitation. Patients with systemic onset JCA develop mild functional limitations, which partially correlate with the more serious impairments. Pulmonary function disorders are a common impairment. Active inflammatory disease might influence functional outcome, but there is no evidence that it influences joint impairment outcome.

Wave-speed-determined flow limitation at peak flow in normal and asthmatic subjects.

The purpose of this study was to examine whether peak expiratory flow is determined by the wave-speed flow-limiting mechanism. We examined 17 healthy subjects and 11 subjects with stable asthma, the latter treated with inhaled bronchodilators and corticosteroids. We used an esophageal balloon and a Pitot-static probe positioned at five locations between the right lower lobe and midtrachea to obtain dynamic area-transmural pressure (A-Ptm) curves as described (O. F. Pedersen, B. Thiessen, and S. Lyager. J. Appl. Physiol. 52: 357-369, 1982). From these curves we obtained cross-sectional area (A) and airway compliance (Caw = dA/dPtm) at PEF, calculated flow at wave speed (Vws = A[A/(Caw*rho)0.5], where rho is density) and speed index is (SI = V/Vws). In 13 of 15 healthy and in 4 of 10 asthmatic subjects, who could produce satisfactory curves, SI at PEF was > 0.9 at one or more measured positions. Alveolar pressure continued to increase after PEF was achieved, suggesting flow limitation somewhere in the airway in all of these subjects. We conclude that wave speed is reached in central airways at PEF in most subjects, but it cannot be excluded that wave speed is also reached in more peripheral airways.

Assessment of accuracy and applicability of a portable electronic diary card spirometer for asthma treatment.

A pocked-sized turbine flowmeter and spirometer device, integrated with an electronic diary card (EDC-spirometer, Micro Medical, U.K.), was tested with a mechanical calibrator, in an outpatient clinic and in the home situation. A screen pneumotachometer was used as flow and volume reference. Ten devices were tested; interdevice variability was small with a mean variation coefficient of 1.1% for both forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) (SD 0.5 and 0.4, respectively) for eight settings of the calibrator. Mean difference from reference was -0.13 l (SD 0.04) for FEV1 (range 0.38-3.16) and 0.09 l s-1 (SD 0.09) for PEF (range 4.2-11.7). No significant deviation from linearity was present. Results obtained in the outpatient clinic confirmed the accuracy of FEV1 and PEF data obtained with the calibrator. However, linear regression analysis showed a mean underestimation of 0.45 l (SD of estimate 0.29) for forced vital capacity over the whole measurement range, probably due to a restricted integration time. In 10 optimally-treated chronic obstructive pulmonary disease patients in a family practice, PEF measurements were done in the home situation, both with the EDC spirometer and a mini-Wright peak flow meter. No significant differences in the diurnal variation of PEF were found. The PEF data from the mini-Wright meter were corrected for earlier reported flow-dependent systematic deviations. In the home situation, patients preferred the EDC spirometer. It is concluded that this device is applicable in the follow-up and treatment of asthma at home.

Improvement of tidal breathing pattern analysis in children with asthma by on-line automatic data processing.

The time taken to achieve peak tidal expiratory flow as a proportion of total expiratory time (t PTEF/t E) during tidal breathing (TB) is used as a parameter of airway obstruction in children with asthma. Curve selection bias is one of the most important limitations to the method. This study evaluates three curve selection methods, including a computer program, which on-line selects and analyses TB curves (Masterscreen Paediatric; Jaeger, Germany). TB analysis was performed in 26 children (aged 4-7 yrs) with asthma, before and after methacholine provocation and after subsequent bronchodilatation. Levels and stability of TB parameters derived from computer-selected, unselected and unbiased eye-selected curves were compared. t PTEF/t E ratios of the computer-selected curves agreed well with the unbiased eye-selected curves (limits of agreement -4.8 and +5.8%), but were significantly different from the ratios of unselected curves. Computer-derived t PTEF/t E ratios had the highest level of stability: the reliability coefficient of baseline measurements was 0.96 for computer selection, 0.84 for eye selection and 0.87 for no selection (reliability index = 1 at maximal stability). Tidal volume, respiratory rate, inspiratory and expiratory time were also assessed accurately by the computer program. The mean t PTEF/t E ratio (computer selection) dropped after methacholine provocation (from 30 +/- 9 to 22 +/- 9% at provocative dose at which forced expiratory volume in one second had dropped > or = 20% from baseline (FEV1-PD20 level), p < 0.001) and was restored after bronchodilation (30 +/- 6%; p < 0.001). We conclude that on-line computer analysis is preferable to no selection and to by-eye selection. The use of the program avoids curve selection bias and enhances the applicability of tidal breathing analysis as a measure of airflow obstruction in young children.

Tidal breathing analysis as a measure of airway obstruction in children three years of age and older.

This study was designed to evaluate the value and applicability of tidal breathing pattern analysis to assess airflow obstruction in young children. The time needed to reach maximal tidal expiratory flow (TME) divided by total expiratory time (TE) was measured in 228 healthy children 3 to 11 yr of age, 64 patients with asthma, and 12 children with cystic fibrosis. In 70 patients both TME/TE and forced maximal expiratory flow volume (MEFV) parameters were measured. The mean TME/TE in healthy subjects was 43.0 +/- 7.6%. The within-subject reproducibility was high (repeatability index, 5.3%). In the asthmatic patients the mean TME/TE was significantly lower (30.0 +/- 8.2%, p < 0.001), and it increased to 36.5 +/- 7.9% after bronchodilation (n = 44, p < 0.001). The TME/TE level of the subgroup of patients with asthma and FEV1/FVC > or = 0.80 was lower when compared with age-matched normal subjects (30.9 +/- 8.5, p < 0.0001), but it was in a higher range when compared with asthmatics with FEV1/FVC < 0.80 (25.9 +/- 7.9, p < 0.001). In the cystic fibrosis group the mean TME/TE was 27.4 +/- 10.7% without a significant change after bronchodilation. TME/TE correlated significantly with MEFV parameters. Tidal breathing analysis proved easy to perform in children older than 3 yr of age. The TME/TE ratio may be a reliable and simple indicator for airway obstruction.

[Inhalation therapy in children with asthma]. / Inhalatietherapie bij kinderen met astma.

Inhalation therapy for childhood asthma is safe and effective. It has the advantages of a low dose, a rapid effect and a wide therapeutic range. For the majority of children the available medications make it possible now to treat asthma optimally, provided that special care is taken to select the appropriate inhalation devices, and repeated practical instructions are given.