Frequency Of Asthma Symptoms Research Articles

Machine learning-driven identification of air toxic combinations associated with asthma symptoms among elementary school children in Spokane, Washington, USA

Air toxics are atmospheric pollutants with hazardous effects on health and the environment. Although methodological constraints have limited the number of air toxics assessed for associations with health and disease, advances in machine learning (ML) enable the assessment of a much larger set of environmental exposures. We used ML methods to conduct a retrospective study to identify combinations of 109 air toxics associated with asthma symptoms among 269 elementary school students in Spokane, Washington. Data on the frequency of asthma symptoms for these children were obtained from Spokane Public Schools. Their exposure to air toxics was estimated by using the Environmental Protection Agency's Air Toxics Screening Assessment and National Air Toxics Assessment. We defined three exposure periods: the most recent year (2019), the last three years (2017–2019), and the last five years (2014–2019). We analyzed the data using the ML-based Data-driven ExposurE Profile (DEEP) extraction method. DEEP identified 25 air toxic combinations associated with asthma symptoms in at least one exposure period. Three combinations (1,1,1-trichloroethane, 2-nitropropane, and 2,4,6-trichlorophenol) were significantly associated with asthma symptoms in all three exposure periods. Four air toxics (1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, BIS (2-ethylhexyl) phthalate (DEHP), and 2,4-dinitrophenol) were associated only in combination with other toxics, and would not have been identified by traditional statistical methods. The application of DEEP also identified a vulnerable subpopulation of children who were exposed to 13 of the 25 significant combinations in at least one exposure period. On average, these children experienced the largest number of asthma symptoms in our sample. By providing evidence on air toxic combinations associated with childhood asthma, our findings may contribute to the regulation of these toxics to improve children's respiratory health.

Development and validation of a new asthma questionnaire to help achieve a high level of control in school-age children and adolescents

BackgroundMaintaining good asthma control minimizes the risk of exacerbations and lung function decline and is a primary goal of asthma management. The Japanese Pediatric Asthma Guidelines (JPGL) employs different classification criteria for control status from other guidelines, stressing a higher level of control. Based on JPGL, we previously developed a caregiver-completed questionnaire for assessing and achieving best asthma control in preschoolers. In this study, we aimed to develop a questionnaire for school-age children and adolescents. MethodsA working questionnaire comprising 14 items for patients and 34 items for caregivers was administered to 362 asthma patients aged 6–15 years and their caregivers. Separately, physicians filled out a questionnaire to determine JPGL-defined control. Logistic regression analysis was performed to construct a model to predict control levels using data from a randomly selected set of completed questionnaires from two-thirds of the subjects. Validation was performed using the remaining questionnaires. ResultsA set of 7 questions, encompassing self-assessed control status at the time of the visit and in the past month, and nocturnal/early morning asthma symptoms for patients and frequency of asthma symptoms, dyspnea, rescue beta-agonist use, and asthma hospitalization for caregivers, were selected and the 7-item model showed a good statistical fit with AIC of 110.5. The model has been named the Best Asthma Control Test for School Children and Adolescents (Best ACT-S). Best ACT-S scores differed significantly in the hypothetical direction among the groups of different JPGL-defined control levels, step-up/down treatment decisions, and presence/non-presence of exacerbations in the previous year. ConclusionsThe Best ACT-S is a valid questionnaire for children/adolescents aiming for best asthma control.

STUDI LITERATUR TENTANG : TEKNIK BUTEYKO DAN TEKNIK LATIHAN PERNAPASAN DIAFRAGMA TERHADAP PUNCAK LAJU ALIRAN PERNAPASAN PASIEN ASMA

Asthma is a disease that is often found in the community, based on data from the World Health Organization in 2018, as many as 300 million asthma sufferers and 225 thousand sufferers died of asthma worldwide. Buteyko technique and diaphragmatic breathing exercise technique can be one of the non-pharmacological adjunct therapies to reduce asthma symptoms also can increase peak expiratory flow. Besides, both of these techniques are still rare people who know that the buteyko technique and diaphragmatic breating exercise can reduce the frequency of asthma symptoms. The purpose of this literature review study is to determine the effectiveness of the Buteyko technique and diaphragmatic breathing exercise on peak expiratory flow rates in asthma patients. In this literature study Journal searches were traced nationally and internationally through Google Schoolar, Pubmed, and DOAJ published from 2010-2020 using selected keywords namely: ((((asthma) AND buteyko) AND diaphragmatic breating exercise) OR breathing exercise) OR muscle training. Based on the literature search results through publication in the database and using keywords that have been adapted to MeSH, researchers get 21 articles that match these keywords. An assessment based on the eligibility of the inclusion and exclusion criteria was found as many as 10 articles that could be used in the literature review. Based on the analysis and synthesis of the article, it can be concluded that the effectiveness of the Buteyko technique and diaphragmatic breathing exercise on peak expiratory flow rates it can be concluded that there is no significant difference between the two interventions in increasing peak expiratory flow rate.

Perimenstrual Asthma and Premenstrual Disorders in Adolescents with Asthma

IntroductionAsthma is a common chronic disease in pediatric patients, and perimenstrual asthma (PMA) refers to the worsening of asthma symptoms during the perimenstrual period, mainly reported in adult women. However, there is limited information regarding the exacerbation of symptoms in the presence of premenstrual disorders (PMDs) in adolescents. This pilot observational study aims to investigate the frequency and potential association of PMA and PMDs in a clinical sample of adolescents with asthma. Patients and MethodsThe study included 50 adolescents (aged 12-18 years, mean 16.08 ± 2.35) with asthma and at least 2 years of gynecological age. The participants completed the Asthma Control Test (ACT) to assess asthma control (considered pathological if ACT score<20) and the modified Premenstrual Symptoms Screening Tool for Adolescents (PSST-A) to evaluate PMDs. ResultsA total of 75.5% of adolescents reported PMA. The prevalence of premenstrual symptoms did not significantly differ between the PMA and no-PMA group. Among the study sample, 38.7% experienced symptoms indicative of moderate/severe premenstrual syndrome (PMS), and 8.1% exhibited symptoms of premenstrual dysphoric disorder (PMDD). Compared to no-PMA group, patients with PMA showed a significant impairment in daily and home activities (p=0.03 and p=0.02, respectively) and exhibited a difference in the frequency of asthma symptoms (p<0.001) and medication use (p=<0.01). ConclusionsPerimenstrual worsening of asthma symptoms may be common in adolescents with severe form of asthma. Prospective data collection through menstrual diaries is necessary to further explore the association between PMA and PMDs. Identifying early risk factors for PMA could facilitate the development of preventive strategies and early interventions for adolescents with asthma.

Prevalence of Allergic Diseases and Risk Factors in Preschool Children

Allergic diseases are very common in children. The aim of this study is to obtain information about the frequency and risk factors of allergic diseases in kindergarten children aged 3-6 years. This study was carried out between 13.02.2018 and 30.12.2018 in kindergartens, in accordance with the ISAAC Phase I protocol for children aged 3-6 years. The study was carried out by distributing 3000 questionnaires in 20 kindergartens. 2001 out of 2040 collected questionnaires were included in the study. Of the participants, 986 (49.3%) were female and 1015 (50.7%) were male. The frequency of asthma symptoms was 30.4% (n=608). The frequency of allergic rhinitis symptoms was found to be 37.1% (743 people). The risk of asthma symptoms was significantly higher in males, those whose mothers smoked during pregnancy, those born preterm, those with a smoker at home and those with mold in the home (p

Impact of Spirometry Race-Correction on Preadolescent Black and White Children.

Race-correction for Black patients is standard practice in spirometry testing. History suggests that these corrections are at least partially a result of racist assumptions regarding lung anatomy among Black individuals, which can potentially lead to less frequent diagnoses of pulmonary diseases in this population. To evaluate the impact of race-correction in spirometry testing among Black and White preadolescents, and examine the frequency of current asthma symptoms in Black children who were differentially classified depending on whether race-corrected or race-uncorrected reference equations were deployed. Data from Black and White children who completed a clinical examination at age 10 years from a Detroit-based unselected birth cohort were analyzed. Global Lung Initiative 2012 reference equations were applied to spirometry data using both race-corrected and race-uncorrected (ie, population-average) equations. Abnormal results were defined as values less than the fifth percentile. Asthma symptoms were assessed concurrently using the International Study of Asthma and Allergies in Childhood questionnaire, while asthma control was assessed using the Asthma Control Test. The impact of race-correction on forced expiratory volume in 1 second (FEV1)/forced vital capacity ratio was minimal, but abnormal classification of FEV1 results more than doubled among Black children when race-uncorrected equations were used (7% vs 18.1%) and were almost 8 times greater based on forced vital capacity classification (1.5% vs 11.4%). More than half of Black children differentially classified on FEV1 (whose FEV1 was classified as normal with race-corrected equations but abnormal with race-uncorrected equations) experienced asthma symptoms in the past 12 months (52.6%), which was significantly higher than the percentage of Black children consistently classified as normal (35.5%, P=.049), but similar to that of Black children consistently classified as abnormal using both race-corrected and race-uncorrected equations (62.5%, P= .60). Asthma Control Test scores were not different based on classification. Race-correction had an extensive impact on spirometry classification in Black children, and differentially classified children had a higher rate of asthma symptoms than children consistently classified as normal. Spirometry reference equations should be reevaluated to be aligned with current scientific perspectives on the use of race in medicine.

Previous tuberculosis infection associated with increased frequency of asthma and respiratory symptoms in a Nordic-Baltic multicentre population study.

Tuberculosis (TB) infection induces profound local and systemic, immunological and inflammatory changes that could influence the development of other respiratory diseases; however, the association between TB and asthma is only partly understood. Our objective was to study the association of TB with asthma and respiratory symptoms in a Nordic-Baltic population-based study. We included data from the Respiratory Health in Northern Europe (RHINE) study, in which information on general characteristics, TB infection, asthma and asthma-like symptoms were collected using standardised postal questionnaires. Asthma was defined based on asthma medication usage and/or asthma attacks 12 months prior to the study, and/or by a report of ≥three out of five respiratory symptoms in the last 12 months. Allergic/nonallergic asthma were defined as asthma with/without nasal allergy. The associations of TB with asthma outcomes were analysed using logistic regressions with adjustments for age, sex, smoking, body mass index and parental education. We included 8379 study participants aged 50-75 years, 61 of whom reported having had TB. In adjusted analyses, participants with a history of TB had higher odds of asthma (OR 1.99, 95% CI 1.13-3.47). The associations were consistent for nonallergic asthma (OR 2.17, 95% CI 1.16-4.07), but not for allergic asthma (OR 1.20, 95% CI 0.53-2.71). We found that in a large Northern European population-based cohort, persons with a history of TB infection more frequently had asthma and asthma symptoms. We speculate that this may reflect long-term effects of TB, including direct damage to the airways and lungs, as well as inflammatory responses.

The Frequency of Asthma and Allergy Symptoms in Adults and its Related Factors

The Frequency of Asthma and Allergy Symptoms in Adults and its Related Factors

Patient experience of moderate asthma attacks: qualitative research in the USA and Germany

BackgroundThere is limited information available on the impact of moderate asthma exacerbations, often called “asthma attacks” (i.e., those not requiring hospitalisation or treatment with systemic corticosteroids) on patients’ lives. This multi-country qualitative study explored the patient experience of these events.MethodsSemi-structured concept elicitation interviews were conducted in the USA and Germany with adult patients with asthma who had experienced a moderate asthma exacerbation in the prior 30 days. Physicians with experience in managing patients with asthma were also interviewed. Interviews explored patients’ experience of symptoms and impact of moderate exacerbations and associated exacerbation triggers and treatment patterns. Physicians were also asked about their interpretation of a clinical definition and treatment of a moderate exacerbation.ResultsTwenty-eight patient (n = 20 in the USA, n = 8 in Germany) and six physician (n = 3 in the USA, n = 3 in Germany) interviews were conducted. During their moderate exacerbation, all patients reported experiencing shortness of breath, which many considered to be severe and the most bothersome symptom. Wheezing was also reported by all patients and considered severe by two thirds of patients. Most patients also reported coughing and chest tightness. All or almost all patients reported that moderate exacerbation caused fatigue/tiredness and impacted their physical functioning, emotional functioning, activities of daily living and work/school life. Most patients reported using rescue or maintenance inhalers to alleviate symptoms of the exacerbation. Conceptual saturation (i.e., the point at which no new concepts are likely to emerge with continued data collection) was achieved. Findings were used to develop a patient-focused conceptual model of the experience of moderate asthma exacerbations, outlining concepts related to triggers, symptoms, impact, and treatment from the patient perspective. Physician data was consistent with patient reports and complemented the conceptual model.ConclusionsFindings from concept elicitation interviews highlight the increased frequency, duration and severity of asthma symptoms and increased rescue medication use during moderate asthma exacerbations compared with the typical daily asthma experience, which have a substantial impact on patients’ lives.

The Effects of Second-hand Smoke Exposure on Asthma Symptoms in Children

Objective − The aim of study was to evaluate the effects of parental smoking and tobacco smoke exposure (TSE) on asthma symptoms in children, and to raise awareness of the detrimental effects of TSE for asthmatic children.Methods − A modified and validated questionnaire on TSE was completed by 76 parents and their children who were being treated at Srebrnjak Children’s Hospital for asthma. Patients filled in a standardized ACT questionnaire about their asthma symptoms, whereas parental smoking data were derived from a questionnaire filled in by the parents. The answers were structured as ordinal and categorical variables. The non-parametric Mann-Whitney U test and Kruskal-Wallis test were performed.Results −There are statistically significant differences in the frequency of asthma symptoms in children depending on whether household members smoked cigarettes, with statistically significant differences in the frequency of asthma symptoms in children depending on whether their parents smoked cigarettes outside the house, only in one/certain room or everywhere in the house. 34.1% of smoking parents vs 9.4% of nonsmoking parents allow smoking in a car while the child is riding in it. 40.9% of parents who smoke vs 21.9% of non-smoking parents believe that their child is exposed to tobacco smoke somewhere other than in their household or car.Conclusion − TSE is associated with more symptoms and worse asthma control in asthmatic children.

Prevalence of Rhinitis Symptoms Among 16 to 18 Years Old Adolescents in Saudi Arabia

The present study was designed to estimate the prevalence of rhinitis symptoms among secondary school students in Saudi Arabia A cross-sectional study was conducted among children from secondary schools in the city of Riyadh. The study utilised the International Study of Asthma and Allergies in Children (ISAAC) questionnaire. Among the 3073 students (1504 boys and 1569 girls), the prevalence of life-time rhinitis, rhinitis in the past 12 months, and hay fever were 43.8%, 38.6% and 21.3%, respectively. There was a significant difference between boys and girls in the prevalence of life-time rhinitis (41% versus 46.5%, p = 0.02) and the prevalence of rhinitis in the past 12 months (35.1% versus 41.9%, p = 0.001). There was no significant difference between boys and girls in the prevalence of hay fever (22.5% versus 20.2%, p = 0.144). The prevalence of asthma symptoms among students with life-time rhinitis and hay fever were 35.4% and 39.9%, respectively. Asthma symptoms were strongly linked with life-time rhinitis (Odds Ratio [OR] = 2.5, p < 0.001) and hay fever (OR = 2.4, p value < 0.001). The prevalence of rhinitis symptoms is high among 16 to 18 years old adolescents in Saudi Arabia, and symptoms are more common in girls compared to boys. Rhinitis symptoms are also associated with a high frequency of asthma symptoms.

Ozone Pollution, Perceived Support at Home, and Asthma Symptom Severity in the Adolescent Sample of the California Health Interview Survey

BackgroundOutdoor air pollution, including ozone (O3) pollution, and childhood family environments may interact and impact asthma exacerbations in children. Previous epidemiology studies have primarily focused on stress in the home, rather than support, and whether psychosocial factors modify the association between pollution and health outcomes, rather than whether pollution exposure modifies associations between psychosocial factors and health outcomes.MethodsData from the cross-sectional 2003 representative, population-based California Health Interview Survey were linked with air quality monitoring data on O3 pollution from the California Air Resources Board. Adolescents (N = 209) ages 12–17 who reported an asthma diagnosis and lived within 5 mi of the nearest air monitoring station had linked O3 data for a 12-month period preceding the survey interview date. Adolescents reported perceived available support from an adult at home and frequency of asthma symptoms.ResultsIn unadjusted models, for adolescents living in high O3 pollution regions, greater perceived support was related to lower asthma symptom frequency. Follow-up analyses suggested that the most plausible interpretation of the interaction was that O3 exposure modified the association between perceived support and symptom frequency. O3 × perceived support interactions were not statistically significant after adjusting for covariates.ConclusionsThese data provide preliminary evidence that the association between the lack of support in the home environment and worse asthma symptoms may be stronger in areas with higher O3 exposure. Future work may benefit from incorporating personal pollution exposure assessments, comprehensive family environment assessments, and longitudinal follow-up of asthma exacerbations over time.

Associations between Daily Ambient Air Pollution and Pulmonary Function, Asthma Symptom Occurrence, and Quick-Relief Inhaler Use among Asthma Patients.

Particulate matter (PM) is harmful to human health, especially for people with asthma. The goal of this study was to enhance the knowledge about the short-term effects of daily air concentrations of PM on health outcomes among asthma patients. The novelty of this study was the inclusion of a homogeneous group of patients (N = 300) with diagnosed and partly controlled asthma. Patients recorded their symptoms, asthma quick-relief inhaler use, and peak expiratory flow (PEF) measurements in a diary for two weeks. Data on particulate air pollution were obtained from stationary monitoring stations. We have shown that particulate pollutants (PM10 and PM2.5) are associated with significant deterioration of PEF and an increase in the frequency of early asthma symptoms, as well as asthma quick-relief inhaler use. These effects are observed not only on the day of exposure, but also on the following day. For public health practice, these results support the rationale for using peak-flow meters as necessary devices for proper asthma self-management and control, especially in locations where the air is polluted with particles. This may decrease the number of asthma patients seeking medical help.

Safety of Live Attenuated Influenza Vaccine in Children With Asthma.

Asthma is considered a precaution for use of quadrivalent live attenuated influenza vaccine (LAIV4) in persons aged ≥5 years because of concerns for wheezing events. We evaluated the safety of LAIV4 in children with asthma, comparing the proportion of children with asthma exacerbations after LAIV4 or quadrivalent inactivated influenza vaccine (IIV4). We enrolled 151 children with asthma, aged 5 to 17 years, during 2 influenza seasons. Participants were randomly assigned 1:1 to receive IIV4 or LAIV4 and monitored for asthma symptoms, exacerbations, changes in peak expiratory flow rate (PEFR), and changes in the asthma control test for 42 days after vaccination. We included 142 participants in the per-protocol analysis. Within 42 days postvaccination, 18 of 142 (13%) experienced an asthma exacerbation: 8 of 74 (11%) in the LAIV4 group versus 10 of 68 (15%) in the IIV4 group (LAIV4-IIV4 = -0.0390 [90% confidence interval -0.1453 to 0.0674]), meeting the bounds for noninferiority. When adjusted for asthma severity, LAIV4 remained noninferior to IIV4. There were no significant differences in the frequency of asthma symptoms, change in PEFR, or childhood asthma control test/asthma control test scores in the 14 days postvaccination between LAIV4 and IIV4 recipients. Vaccine reactogenicity was similar between groups, although sore throat (P = .051) and myalgia (P <.001) were more common in the IIV4 group. LAIV4 was not associated with increased frequency of asthma exacerbations, an increase in asthma-related symptoms, or a decrease in PEFR compared with IIV4 among children aged 5 to 17 years with asthma.

Monitoring of Nighttime Respiratory Patterns to Alert for Changes in Chronic Asthma Management

The frequency and severity of nighttime asthma symptoms may alert providers for the need to alter or reinforce the need for chronic asthma therapy. We hypothesized that the availability of this objective information could be used to achieve better asthma control and reduce adverse events.

The impact of converting a power plant from coal to natural gas on pediatric acute asthma

Background and Objectives Air pollutants play a pivotal role in the frequency and severity of asthma symptoms. As cleaner air initiatives are increasingly being implemented, it is important to appraise how these changes relate to acute pediatric asthma. The objective of this study is to evaluate the effect of a Gas and Electric Company’s transition from using coal to natural gas as their fuel source on pediatric asthma-related illnesses in Louisville, KY. Methods Data were collected for children 2–17 years old from a large regional healthcare system, for which an asthma-related primary diagnosis was present between April 1, 2013 and April 1, 2018. Using an interrupted time series design, we analyzed monthly rates of asthma-related visits to urgent care (UC) and emergency departments (ED). Segmented Poisson regression models were used to assess whether the power company’s transition was associated with changes in trends of asthma-related visits. Results There were a total of 7,735 subjects who met inclusion criteria. Prior to the complete factory transition from coal to natural gas, the mean monthly rate for asthma-related visits was 163.9. After the transition, we observed a significant decrease to a mean monthly rate of 100.3 asthma-related visits (p < 0.001). In addition, the proportion of inpatient (23.7% vs. 30.5%, p < 0.001) visits significantly increased, while ED & UC (76.3 vs. 69.5%, p < 0.001) were significantly decreased. Conclusion Converting an electrical power plant from coal to natural gas lead to a profound and sustained decrease in pediatric acute asthma exacerbation in Louisville, KY.

The Melbourne epidemic thunderstorm asthma event 2016: a 5-year longitudinal study.

In 2016, Melbourne was struck by the world's largest and most devastating epidemic thunderstorm asthma (ETSA) episode. While affected individuals displayed worsened short-term asthma control, little is known about their longer-term natural history, nor about interventions that restore control. We assessed the asthma symptomatology and related behaviours of ETSA-affected individuals through a single-centre prospective 5-year longitudinal study. We embedded an open-label observational trial investigating the role of grass pollen sublingual tablet (Oralair) allergen immunotherapy in improving asthma and allergic rhinitis symptoms. Allergic rhinitis symptom severity, frequency of asthma symptoms and inhaled corticosteroid usage were assessed via questionnaire yearly. In 2018, a subgroup of participants was enrolled in an observational study of Oralair treatment compared to control. The active group received Oralair from 2019 to 2021; both groups were followed-up for 5 years. Subgroup analyses were performed for participants with complete datasets, and who completed the trial per-protocol. Year-on-year data across 5 years was available for 30 participants. The rate of persistent asthma symptoms declined from 37% to 7% in 2016 to 2021. Only 10%-27% of participants reported being completely asymptomatic in any given year. The inhaled preventer prescription rate was 67%, with only 35% being adherent. Twenty-seven participants with available data completed the Oralair trial per-protocol. No significant difference was noted between control and active groups for allergic rhinitis symptoms or asthma control, although the Oralair group saw a significant improvement in asthma control comparing 2019 with 2021. This is the longest documented follow-up of ETSA-affected individuals. Five years following sentinel event, there was progressive reduction but some persistence in asthma symptoms. Oralair allergen immunotherapy did not further improve allergic rhinitis or asthma symptoms compared to control, but there were no further ETSA events to test a protective effect during the study period.

Asthma Daytime Symptom Diary (ADSD) and Asthma Nighttime Symptom Diary (ANSD): Measurement Properties of Novel Patient-Reported Symptom Measures

The Asthma Daytime Symptom Diary (ADSD) and the Asthma Nighttime Symptom Diary (ANSD) were developed to meet the need for standardized patient-reported measures of asthma symptoms to assess treatment trial outcomes in adults and adolescents. To determine scoring and evaluate the measurement properties of the ADSD/ANSD. Adolescents (12-17 years) and adults (18+ years) with asthma completed draft 8-item electronic versions of the ADSD/ANSD for 10 days alongside the Adult Asthma Symptom Daily Scales (AASDS) and a Patient Global Impression of Severity (PGIS). Using classical and modern psychometric methods, initial analyses evaluated the performance of ADSD/ANSD items to inform scoring. Subsequent analyses evaluated the reliability and validity of ADSD/ANSD scores. A demographically and clinically diverse sample (n= 130 adolescents; n= 89 adults) was recruited. Item performance was generally strong. However, items assessing chest pressure and mucus/phlegm demonstrated redundancy and poorer performance and were removed. Principal-components analysis, confirmatory factor analysis, and item response theory supported combining items to form 6-item total ADSD/ANSD scores. Internal consistency (α= 0.94-0.95) and test-retest reliability (intraclass correlation coefficient= 0.86-0.95) were strong. Strong correlations (r= 0.72-0.80) were observed between ADSD scores and AASDS items assessing asthma symptom frequency, bother, and impact on activities. Significant differences (P < .001) in mean ADSD/ANSD scores were observed between groups categorized by asthma severity (PGIS), asthma control, inhaler use, nebulizer use, activity limitations, and nighttime awakenings. The ADSD/ANSD items and scores demonstrated strong reliability and validity. Implementation of the measures in interventional studies will enable the evaluation of responsiveness and meaningful within-patient change.

PRS33 Patient Experience of Moderate Exacerbations in Asthma: Development of a Conceptual Model

Exacerbations of asthma present a significant burden to patients and health-care systems and are common endpoints in clinical studies. Whilst severe exacerbations are well understood, moderate exacerbations of asthma (requiring a temporary change in treatment although not requiring hospitalization) are less so, making their interpretation as endpoints difficult. Concept elicitation interviews were conducted to characterize patient experience of moderate exacerbations and develop a conceptual model. 20 US patients, with clinician confirmed diagnosis of moderate/severe asthma and experience of a moderate exacerbation =<30 days prior to the interview, participated in 60-minute semi-structured interviews about their experience. Interview transcripts were analyzed using thematic analysis. Conceptual saturation was achieved within 20 interviews. The resulting conceptual model relates exacerbation triggers (similar to those of severe exacerbations) to symptoms of moderate exacerbations and the subsequent impact of these events. The model suggests moderate asthma exacerbations are characterized by increased severity, frequency and duration of symptoms above day-to-day experience. Two key symptoms were reported as most important; shortness of breath and wheezing, as well as coughing, chest tightness, phlegm/mucus and chest pain. Patients increased rescue/maintenance medication use. Night-time awakenings or difficulty falling asleep were also reported. Impacts on health-related quality of life included fatigue and anxiety/fear/panic. Patients stopped or slowed down physical, daily and social activities, missed work or were less productive. Increased frequency, severity and duration of core asthma symptoms, sleep disturbances and increased medication use define a moderate exacerbation from the patient perspective. Symptoms lead to fatigue, emotional distress and avoidance of physical, daily, work, and social activities. Although challenges may exist in identifying moderate exacerbations in clinical practice as patients may not seek healthcare, this conceptual model of moderate asthma exacerbation will be used to plan a patient focused measurement strategy for future clinical development.

Electronic cigarette (e-cigarette) use and frequency of asthma symptoms in adult asthmatics in California

Introduction Electronic cigarettes use is increasing in the United States. One motive for e-cigarette’s popularity is that they wean from combustible cigarettes. Smokers perceive electronic cigarette products as healthier than cigarette smoking and as a useful tool for smoking cessation. However, research has indicated the use of electronic cigarettes may have harmful effects on respiratory function even with short-term use. Respiratory effects of e-cigarette use among asthmatics are little understood. Objective The aim of this study was to determine the association between e-cigarette use and frequency of asthma symptoms among adult asthmatics in California from 2015–2016. Methods This cross-sectional study included a total of 1277 adult asthmatics. The presence of asthma was based on an adult’s self-reported doctor diagnosis. The analysis was controlled for age, education, sex, race, body mass index, and smoking status. Results E-cigarette use was associated with increased odds of having more frequent asthma symptoms (OR = 1.69, CI: 1.20–2.39, p = 0.002; ORadj = 1.65, CI: 1.09–2.49, p = 0.016). Male e-cigarette users were more likely to have more frequent asthma symptoms compared to male nonusers (OR = 1.90, CI: 1.13–3.19, p = 0.015; ORadj = 2.42, CI: 1.28–4.55, p = 0.006). No differences were found between female e-cigarette users and nonusers (OR = 1.43, CI: 0.86–2.37, p = 0.162; ORadj = 1.26, CI: 0.72–2.18, p = 0.162). Conclusion Our findings suggest that e-cigarette use is associated with more frequent asthma symptoms and disproportionally affects male asthmatics.