Electronic monitoring of symptoms and lung function to assess asthma control in children

Multivariate time series approaches to extract predictive asthma biomarkers from prospectively patient-collected diary data: a systematic review

OBJECTIVES

Longitudinal data are common in asthma studies, to assess asthma progression in patients and identify predictors of future outcomes, including asthma exacerbations and asthma control. Different methods can quantify temporal behaviour in prospective patient-collected diary variables to obtain predictive biomarkers of asthma outcomes. The aims of this systematic review were to evaluate methods for extracting biomarkers from longitudinally collected diary data in asthma and investigate associations between them and patient-reported outcomes (PROs) of patients with asthma.

DESIGN

Systematic review and narrative synthesis.

DATA SOURCES

MEDLINE, EMBASE, CINAHL and the Cochrane Library were searched for studies published between January 2000 and July 2023.

ELIGIBILITY CRITERIA

Included studies generated biomarkers from prospective patient-collected peak expiratory flow, symptom scores, reliever use and nocturnal awakenings, and evaluated their associations with asthma PROs, namely asthma exacerbations, asthma control, asthma-related quality of life and asthma severity.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers used standardised methods to screen and extract data from included studies. Study quality and risk of bias were assessed using the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) and the Prediction model Risk Of Bias ASessment Tool (PROBAST), respectively.

RESULTS

24 full-text articles met the inclusion criteria and were included in the review. Generally, higher levels of variability in the diary variables were associated with poorer outcomes, especially increased asthma exacerbation risk, and poor asthma control. There was increasing interest in non-parametric methods to quantify complex behaviour of diary variables (6/24). TRIPOD and PROBAST highlighted a lack of consistent reporting of model performance measures and potential for model bias.

CONCLUSION

Prospectively patient-collected diary variables aid in generating asthma assessment tools, including surrogate endpoints, for clinical trials and predictive biomarkers of adverse outcomes, warranting remote monitoring. Studies consistently lacked robust reporting of model performance. Future research should use diary variable-derived biomarkers.

Domiciliary monitoring of exhaled nitric oxide in the management of asthma: a pilot study

BACKGROUND

Whether asthma patients could benefit from home monitoring for fractional exhaled nitric oxide (flow of 50 mL/s, FeNO50) is unknown. We explore the application value of home monitoring FeNO50 in daily asthma management.

METHODS

Twenty-two untreated, uncontrolled asthma patients were selected. Medical history, blood and sputum samples, pulmonary function, Asthma Control Test (ACT), and other clinical data of the subjects were collected. All subjects underwent daily monitoring for four weeks using a FeNO50 monitor and mobile spirometry (mSpirometry). The diurnal differences and dynamic changes were described. Compare the effect-acting time and the relative plateau of treatment between FeNO50 and mSpirometry monitoring.

RESULTS

In the first two weeks, the morning median (IQR) level of FeNO50 was 44 (35, 56) ppb, which was significantly higher than the evening median level [41 (32, 53) ppb, P = 0.028]. The median (IQR) effect-acting time assessed by FeNO50 was 4 (3, 5) days, which was significantly earlier than each measure of mSpirometry (P < 0.05). FeNO50 reached the relative plateau significantly earlier than FEV1 (15 ± 2 days vs. 21 ± 3 days, P < 0.001). After treatment, the daily and weekly variation rates of FeNO50 showed a gradually decreasing trend (P < 0.05). The ACT score, sputum eosinophils, and blood eosinophils also significantly improved (P ≤ 0.01).

CONCLUSIONS

The daily home monitoring of FeNO50 in asthmatic patients showed significant circadian rhythm, and the sensitivity of FeNO50 in evaluating the response to treatment was higher than mSpirometry. The daily and weekly variation rates of FeNO50 change dynamically with time, which may be used to assess the condition of asthma.

Telemonitoring of pediatric asthma in outpatient settings: A systematic review

Telemonitoring technologies are rapidly evolving, offering a promising solution for remote monitoring and timely management of asthma acute episodes. We aimed to describe current pediatric asthma telemonitoring technologies. A systematic review was conducted until September 2023 on Medline, Scopus, and Web of Science. We included studies of children (0-18 years) with asthma or recurrent wheezing whose respiratory condition was telemonitored outside the healthcare setting. A narrative synthesis was performed. We identified 40 telemonitoring technologies described in 40 studies. The more frequently used technologies for telemonitoring were mobile applications (n = 21) and web-based systems (n = 14). Telemonitoring duration varied between 2 weeks and 32 months. Data collection included asthma symptoms (n = 30), patient-reported outcome measures (PROMs) (n = 11), spirometry/peak flow readings (n = 20), medication adherence (n = 17), inhaler technique (n = 3), air quality (n = 2), and respiratory sounds (n = 2). Both parents and children were the technology target users in most studies (n = 23). Technology training was reported in 23 studies of which 3 provided ongoing support. Automatic feedback was found in 30 studies, mostly related with asthma control. HCP were involved in data management in 27 studies. Technologies were tested in samples from 4 to 327 children, with most studies including school-aged children and/or adolescents (n = 38) and eight including preschool children. This review provides an overview of existing technologies for the outpatient telemonitoring of pediatric asthma. Specific technologies for preschool children represent a gap in the literature that needs to be specifically addressed in future research.

Discrepancy between Lung Function Measurements at Home and in the Hospital in Children with Asthma and CF

The Coronavirus pandemic stresses the importance of eHealth techniques to monitor patients at home. Home monitoring of lung function in asthma and cystic fibrosis (CF) may help to detect deterioration of lung function at an early stage, but the reliability is unclear. We investigated whether lung function measurements at home were comparable to measurements during clinical visits. We analysed prospectively collected data of two one-year observational cohort studies in 117 children (36 with CF and 81 with asthma). All patients performed forced expiratory volume in one second (FEV₁) measurements with a monitor at home. Paired FEV₁ measurements were included if the measurement on the home monitor was performed on the same day as the FEV₁ measurement on the pneumotachometer during a two monthly clinical visit. Bland-Altman plots and linear mixed model analysis were used. The mean difference (home measurement was subtracted from clinical measurement) in FEV₁ was 0.18 L in CF (95% confidence interval (CI) 0.08–0.27 L; p < 0.001) and 0.12 L in asthma (95%CI 0.05–0.19 L; p < 0.001). FEV₁ measurements at home were significantly lower than clinically obtained FEV₁ measurements, which has implications for the application of this technique in the daily clinical situation.

Early detection of pulmonary exacerbations in children with Cystic Fibrosis by electronic home monitoring of symptoms and lung function

Pulmonary exacerbations (PEx) in Cystic Fibrosis (CF) are associated with an increased morbidity and even mortality. We investigated whether early detection of PEx in children with CF is possible by electronic home monitoring of symptoms and lung function. During this one-year prospective multi-centre study, 49 children with CF were asked to use a home monitor three times a week. Measurements consisted of a respiratory symptom questionnaire and assessment of Forced Expiratory Volume in one second (FEV1). Linear mixed-effects and multiple logistic regression analyses were used. In the 2 weeks before a PEx, the Respiratory Symptom Score (RSS) of the home monitor increased (p = 0.051). The FEV1 as percentage of predicted (FEV1%pred) did not deteriorate in the 4 weeks before a PEx. Nevertheless, the FEV1%pred at the start of exacerbation was significantly lower than the FEV1%pred in the non-exacerbation group (mean difference 16.3%, p = 0.012). The combination of FEV1%pred and RSS had a sensitivity to predict an exacerbation of 92.9% (CI 75.0-98.8%) and a specificity of 88.9% (CI 50.7-99.4%). The combination of home monitor FEV1%pred and RSS can be helpful to predict a PEx in children with CF at an early stage.

Introduction of a new paediatric asthma guideline: Effects on asthma control levels

BACKGROUND

In 2008, a new national paediatric asthma management guideline based on the international Global Initiative for Asthma (GINA) guideline was launched in the Netherlands. We studied whether asthma control and treatment regimens improved after introduction of the guideline by comparing survey data before and after the guideline introduction.

METHODS

Two comparable groups of children (6-16 years) with asthma were included before (2004) and after (2013) the introduction of the guideline. Children, parents and paediatricians completed questionnaires about asthma symptoms, medication and healthcare use. Spirometry was performed.

RESULTS

Data of 209 patients were analysed. Level of asthma control did not improve between 2004 and 2013 with a proportion of (partly) controlled asthmatics of 51% in 2004 and 59% in 2013 (p = 0.28). In 2013, paediatricians characterized 76% of children as (partly) controlled, while 59% of children was (partly) controlled according to GINA criteria (p < 0.05). Step-down treatment in controlled patients was more applied by paediatricians in 2013 compared to 2004 (from 8 to 40%, p < 0.05). Step-up treatment in uncontrolled patients did not improve.

CONCLUSIONS

Asthma control did not improve after the introduction of the new guideline. Compared to 2004, an improvement was observed in step-down treatment in patients with controlled disease.

Can exhaled volatile organic compounds predict asthma exacerbations in children?

BACKGROUND

Asthma control does not yet meet the goals of asthma management guidelines. Non-invasive monitoring of airway inflammation may help to improve the level of asthma control in children.

OBJECTIVES

(1) To identify a set of exhaled volatile organic compounds (VOCs) that is most predictive for an asthma exacerbation in children. (2) To elucidate the chemical identity of predictive biomarkers.

METHODS

In a one-year prospective observational study, 96 asthmatic children participated . During clinical visits at 2 month intervals, asthma control, fractional exhaled nitric oxide, lung function (FEV₁, FEV₁/VC) and VOCs in exhaled breath were determined by means of gas chromatography time-of-flight mass spectrometry. Random Forrest classification modeling was used to select predictive VOCs, followed by plotting of receiver operating characteristic-curves (ROC-curves).

RESULTS

An inverse relationship was found between the predictive power of a set of VOCs and the time between sampling of exhaled breath and the onset of exacerbation. The sensitivity and specificity of the model predicting exacerbations 14 days after sampling were 88% and 75%, respectively. The area under the ROC-curve was 90%. The sensitivity for prediction of asthma exacerbations within 21 days after sampling was 63%. In total, 7 VOCs were selected for the classification model: 3 aldehydes, 1 hydrocarbon, 1 ketone, 1 aromatic compound, and 1 unidentified VOC.

CONCLUSION

VOCs in exhaled breath showed potential for predicting asthma exacerbations in children within 14 days after sampling. Before using this in clinical practice, the validity of predicting asthma exacerbations should be studied in a larger cohort.

Respiratory allergies in childhood: Recent advances and future challenges

The burden of allergic airway diseases still represents a major health problem in childhood. Despite many different options are currently available for the diagnostic work-up and management, the overall disease control in terms of impact on quality of life, morbidity and mortality, is not yet satisfactory. The extreme variability of individual risk factors and severity determinants may account for it. On the other side, the knowledge of the multifaceted allergy background could pave the way to primary prevention, early intervention and disease course modification. In fact, most of current research is focusing on the identification of biological and clinical predictive markers of allergy and asthma onset. This review aims at summarizing the latest achievements concerning the complex inter-relation between genetic predisposition and environmental factors, and their impact on prevention strategies and early identification of at risk subjects. An update on the diagnostic and monitoring tools as well as an insight into the newest treatments options is also provided.

Advances in pediatric asthma in 2014: Moving toward a population health perspective

Last year's "Advances in pediatric asthma in 2013: Coordinating asthma care" concluded that, "Enhanced communication systems will be necessary among parents, clinicians, health care providers and the pharmaceutical industry so that we continue the pathway of understanding the disease and developing new treatments that address the unmet needs of patients who are at risk for severe consequences of unchecked disease persistence or progression." This year's summary will focus on further advances in pediatric asthma related to prenatal and postnatal factors altering the natural history of asthma, assessment of asthma control, and new insights regarding the management of asthma in children as indicated in Journal of Allergy and Clinical Immunology publications in 2014. A major theme of this review is how new research reports can be integrated into medical communication in a population health perspective to assist clinicians in asthma management. The asthma specialist is in a unique position to convey important messages to the medical community related to factors that influence the course of asthma, methods to assess and communicate levels of control, and new targets for intervention, as well as new immunomodulators. By enhancing communication among patients, parents, primary care physicians, and specialists within provider systems, the asthma specialist can provide timely information that can help to reduce asthma morbidity and mortality.