Environmental factors relevant to difficult asthma

Asthma control and associated risk factors among adults with current asthma: Findings from 2019 behavioral risk factor surveillance system asthma call-back survey

BACKGROUND

Despite the availability of effective treatments, many adults with asthma have uncontrolled asthma. Uncontrolled asthma can lead to severe exacerbations. This study aimed to determine the prevalence and predictors of uncontrolled asthma among adults (≥18 years) with current asthma in the United States.

METHODS

We analyzed the 2019 Behavior Risk Factor Surveillance System Asthma Call-Back Survey data from 27 states. Asthma control status was classified as "well-controlled" or "uncontrolled" according to the National Asthma Education and Prevention guidelines. The study population consisted of 7937 adults (weighted n = 13,793,220) with current asthma. We used multivariable logistic regression models to identify predictors of uncontrolled asthma.

RESULTS

Overall, 62 % of adults with asthma reported having uncontrolled asthma, and 26 % had emergency or urgent care visits or hospitalizations in the past year. Potentially modifiable risk factors associated with uncontrolled asthma included cost barriers to asthma-related healthcare (OR = 2.94; 95%CI 1.96-4.40), complementary and alternative medicine use (OR = 1.84; 95%CI 1.45-2.32), current smoking (OR = 2.25; 95%CI 1.48-3.44), obesity (OR = 1.39; 95%CI 1.02-1.89), COPD (OR = 1.98; 95%CI 1.43-2.74), depression (OR = 1.47; 95%CI 1.16-1.88), fair/poor general health (OR = 1.54; 95%CI 1.14-2.07), household income <$15,000 (OR = 2.59; 95%CI 1.42-4.71), and less than high school education (OR = 2.59; 95%CI 1.42-4.71). Non-modifiable risk factor was Hispanic ethnicity (OR = 1.73; 95%CI 1.09-2.73).

CONCLUSION

Our findings suggest that uncontrolled asthma is common among adults and can be impacted by several factors. Effective asthma control programs are needed to improve asthma management and reduce unnecessary healthcare utilization.

A home visit program for low-income African American children with asthma: Caregivers' perception of asthma triggers and a gap in action

PURPOSE

The goals are to gauge caregivers' knowledge of at-home asthma triggers and identify the areas on which educational campaigns can focus to alleviate a child's asthma symptoms.

DESIGN AND METHODS

Families with children with moderate to severe asthmatic symptoms who had been recently hospitalized or in the emergency room were invited to participate in a home visit program. As part of the home visit, caregivers of the asthmatic children were asked a series of questions on asthma triggers and the measures for eliminating the triggers (N = 218).

RESULTS

Findings show a gap between caregivers' perception of asthma triggers and the actions to mitigate or avoid such triggers.

CONCLUSIONS

Overall findings show that home environments were suboptimal for the management and control of child asthma conditions. Knowledge about home triggers as well as the actions and efforts by caregivers and landlords to mitigate these was found to be inadequate. Even when caregivers are aware of the presence of at-home triggers, actions to minimize exposure to the trigger do not always follow due to a lack of power, resource, and knowledge.

PRACTICE IMPLICATIONS

The findings raise the need for additional research to investigate the reasons for the lack of actions, advocacy for low-income families to live in a healthy environment, continued education and empowerment, and patient/caregiver-doctor partnership. Additionally, the provision of community support through community advocacy and training of culturally competent healthcare providers are needed for the successful management of pediatric asthma among African American children.

A scoping review of mHealth monitoring of pediatric bronchial asthma before and during COVID-19 pandemic

Mobile (m) Health technology is well-suited for Remote Patient Monitoring (RPM) in a patient's habitual environment. In recent years there have been fast-paced developments in mHealth-enabled pediatric RPM, especially during the COVID-19 pandemic, necessitating evidence synthesis. To this end, we conducted a scoping review of clinical trials that had utilized mHealth-enabled RPM of pediatric asthma. MEDLINE, Embase and Web of Science were searched from September 1, 2016 through August 31, 2021. Our scoping review identified 25 publications that utilized synchronous and asynchronous mHealth-enabled RPM in pediatric asthma, either involving mobile applications or via individual devices. The last three years has seen the development of evidence-based, multidisciplinary, and participatory mHealth interventions. The quality of the studies has been improving, such that 40% of included study reports were randomized controlled trials. In conclusion, there exists high-quality evidence on mHealth-enabled RPM in pediatric asthma, warranting future systematic reviews and/or meta-analyses of the benefits of such RPM.

Does allergy explain why some children have severe asthma?

Asthma is a common disease in childhood with a minority of affected children having severe therapy-resistant asthma (STRA). Children with STRA can be differentiated from those with mild-moderate disease by greater allergic sensitization, increased eosinophilic airway inflammation, increased airway remodelling and reduced corticosteroid responsiveness. The aetiology of STRA in children is multifactorial but allergy seems to play a key role. Many children with asthma have coexisting allergic disease, and severe rhinitis seems to be an important driver of STRA in children. Allergies to foods, moulds, pollen and pets have also been associated with severe asthma exacerbations. Identifying allergens that are driving asthma symptoms in children with STRA may provide additional strategies for improving their disease control. Avoidance strategies may be possible. Additional monoclonal antibody therapy with Omalizumab or Mepolizumab may be helpful in children with clinically important polysensitization.

[An analysis of skin prick test reactivity to dust mite in overweight and normal weight children with allergic asthma before and after specific immunotherapy]

OBJECTIVE

To study the skin prick test (SPT) reactivity to house dust mite allergens in overweight and normal weight children with allergic asthma before and after standard subcutaneous specific immunotherapy.

METHODS

Two hundred and fifteen children with allergic asthma who had positive SPT responses to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF) were enrolled. According to the weight index, they were classified into overweight (n=63) and normal weight groups (n=152). Skin indices (SI) to DP and DF were compared between the two groups at 6 months and 1 year after standard subcutaneous specific immunotherapy.

RESULTS

The overweight group had a significantly larger histamine wheal diameter than the normal weight group after controlling the variation in testing time (P<0.05). After controlling the variation in weights, there were significant differences in the SIs to DP and DF before specific immunotherapy and at 6 months and 1 year after specific immunotherapy. At 6 months and 1 year after specific immunotherapy, the SIs to DP and DF were significantly reduced in both groups (P<0.05), and the overweight group had greater decreases in the SIs to DP and DF than the normal weight group.

CONCLUSIONS

The overweight children with allergic asthma have stronger responses to histamine than the normal weight patients. Specific immunotherapy can reduce the reactivity to dust mite allergens in children with allergic asthma. Within one year after specific immunotherapy, the overweight children with allergic asthma have a significantly greater decrease in the reactivity to dust mite allergens than the normal weight patients.

Prevalence and clinical profile of difficult-to-control severe asthma in children: results from pneumology and allergy hospital units in Spain

BACKGROUND

Severe asthma is often poorly controlled and its prevalence in Spanish children is unknown. The aim was to determine the prevalence of difficult-to-control severe asthma in children, the agreement of asthma control between physicians and Spanish Guidelines for Asthma Management (GEMA), and the health-related quality of life (HRQoL) for children and parents.

METHODS

Observational, cross-sectional, two-phase, multicentre study. In the first phase, all children who attended pneumology and allergy units during a three-month period were classified according to physicians' criteria as patients with: asthma, severe asthma, or difficult-to-control severe asthma. Patients aged 6-14 years with severe asthma (difficult-to-control or controlled) were included in the second phase.

RESULTS

12,376 asthmatic children were screened in the first phase. According to physicians' criteria, 8.8% (95% CI 8.3-9.3%) had severe asthma. Of these, 24.2% (95% CI, 21.7-26.8%) had difficult-to-control severe asthma. 207 patients with severe asthma (mean age 10.8 ± 2.3 years; 61.4% male; mean of 5.5 ± 3.4 years since asthma diagnosis) were included in the second phase. Compared to the patients with controlled asthma, children with difficult-to-control asthma had a higher number of exacerbations, emergency room or unscheduled primary care visits in the previous year (p<0.0001, all) and poor HRQoL (p<0.0001, both children and caregivers). 33.3% of patients with controlled asthma according to physicians' criteria were poorly controlled according to GEMA.

CONCLUSIONS

Around one in four asthmatic children with severe disease had difficult-to-control asthma, although one third was underestimated by physicians. Children with difficult-to-control severe asthma had a poor HRQoL that also affected their parents.

Childhood asthma: diagnosis and treatment

Many children suffer from recurrent coughing, wheezing and chest tightness. In preschool children one third of all children have these symptoms before the age of six, but only 40% of these wheezing preschoolers will continue to have asthma. In older school-aged children the majority of the children have asthma. Quality of life is affected by asthma control. Sleep disruption and exercised induced airflow limitation have a negative impact on participation in sports and social activities, and may influence family life. The goal of asthma therapy is to achieve asthma control, but only a limited number of patients are able to reach total control. This may be due to an incorrect diagnosis, co-morbidities or poor inhalation technique, but in the majority of cases non-adherence is the main reason for therapy failures. However, partnership with the parents and the child is important in order to set individually chosen goals of therapy and may be of help to improve control. Non-pharmacological measures aim at avoiding tobacco smoke, and when a child is sensitised, to avoid allergens. In pharmacological management international guidelines such as the GINA guideline and the British Guideline on the Management of Asthma are leading.

Arthropod allergens in urban homes

Dust mites, cockroaches, and pets (cats, dogs) are common in homes worldwide, and many species are the source of potent allergens which cause allergic diseases. These diseases are influenced by genetic predisposition and environmental exposure. Generally, the levels of house dust mite (Der p 1 and Der f 1) and cockroach (Bla g 1, Bla g 2) allergens are used as markers of indoor exposure to arthropods.This article reviews the findings of allergens Der p 1, Der f 1, and Bla g 1 in randomly selected urban households in Zagreb (Croatia) measured from 2006 to 2010 and compares them with exposure to arthropod allergens in other countries. In short, house dust mite allergen levels in Croatian homes are low, but exposure is common; Der p 1 was found in 73 % and Der f 1 in 83 % of the households. By contrast, exposure to cockroach allergen Bla g 1 was both low and uncommon (13 %). Exposure to multiple allergens associated with sensitisation and asthma was not frequent in urban homes in Croatia. However, further studies should include monitoring of both arthropod and pet allergens in high-risk populations in inland and coastal Croatia. They should also investigate a complex dose-response relationship between exposure and sensitisation/asthma development, especially in early childhood.

[Diagnosis and treatment guidelines for difficult-to-control asthma in children]

Children suffering from difficult-to-control asthma (DCA) require frequent appointments with their physician, complex treatment regimes and often admissions to hospital. Less than 5% of the asthmatic population suffer this condition. DCA must be correctly characterised to rule out false causes of DCA and requires making a differential diagnosis from pathologies that mimic asthma, comorbidity, environmental and psychological factors, and analysing the factors to determine poor treatment compliance. In true DCA cases, inflammation studies (exhaled nitric oxide, induced sputum, broncho-alveolar lavage and bronchial biopsy), pulmonary function and other clinical aspects can classify DCA into different phenotypes which could make therapeutic decision-making easier.

Complexity of chronic asthma and chronic obstructive pulmonary disease: implications for risk assessment, and disease progression and control

Although assessment of asthma control is important to guide treatment, it is difficult since the temporal pattern and risk of exacerbations are often unpredictable. In this Review, we summarise the classic methods to assess control with unidimensional and multidimensional approaches. Next, we show how ideas from the science of complexity can explain the seemingly unpredictable nature of bronchial asthma and emphysema, with implications for chronic obstructive pulmonary disease. We show that fluctuation analysis, a method used in statistical physics, can be used to gain insight into asthma as a dynamic disease of the respiratory system, viewed as a set of interacting subsystems (eg, inflammatory, immunological, and mechanical). The basis of the fluctuation analysis methods is the quantification of the long-term temporal history of lung function parameters. We summarise how this analysis can be used to assess the risk of future asthma episodes, with implications for asthma severity and control both in children and adults.

Predicting asthma control and exacerbations: chronic asthma as a complex dynamic model

PURPOSE OF REVIEW

Predicting asthma episodes is notoriously difficult but has potentially significant consequences for the individual, as well as for healthcare services. The purpose of this review is to describe recent insights into the prediction of acute asthma episodes in relation to classical clinical, functional or inflammatory variables, as well as present a new concept for evaluating asthma as a dynamically regulated homeokinetic system.

RECENT FINDINGS

Risk prediction for asthma episodes or relapse has been attempted using clinical scoring systems, considerations of environmental factors and lung function, as well as inflammatory and immunological markers in induced sputum or exhaled air, and these are summarized here. We have recently proposed that newer mathematical methods derived from statistical physics may be used to understand the complexity of asthma as a homeokinetic, dynamic system consisting of a network comprising multiple components, and also to assess the risk for future asthma episodes based on fluctuation analysis of long time series of lung function.

SUMMARY

Apart from the classical analysis of risk factor and functional parameters, this new approach may be used to assess asthma control and treatment effects in the individual as well as in future research trials.

Predictors of Smoking Cessation in Pregnancy and Maintenance Postpartum in Low-Income Women

OBJECTIVE

To describe factors associated with smoking status of low-income women during pregnancy and postpartum.

METHODS

Data from a randomized clinical trial were used to conduct separate analyses on 327 women who smoked at baseline (time at enrollment) and for whom smoking status was available at delivery, and on 109 women who reported not smoking at delivery (quit spontaneously or after study enrollment) and for whom smoking status was available at 6-months postpartum. Salivary cotinine was used to assess the accuracy of self-reported smoking status for the sample as a whole. Data were collected between May 1997 and November 2000.

RESULTS

18% of the 327 baseline smokers stopped smoking before delivery. Cessation was less likely in older women, those reporting Medicaid coverage (vs. commercial or no insurance), who were at a later week of pregnancy at baseline, were more addicted, had a husband/partner who smoked, and did not receive the study intervention. 37% of the 109 women who reported not smoking at delivery maintained abstinence at 6-months postpartum. Factors associated with abstinence were later week of pregnancy at baseline and quitting spontaneously with pregnancy, while women who lived with a smoker were less likely to report abstinence. Spontaneous quitters were less likely to relapse by 6 months postpartum than women who quit smoking later in pregnancy.

CONCLUSIONS

Partner participation in smoking cessation programs for pregnant and postpartum women merits exploration. Lower relapse rates among spontaneous quitters indicate a need to foster an environment that encourages quitting at pregnancy.

Difficult asthma in the pre-school child

The most important aspect of dealing with a pre-school child suspected of having difficult asthma, is to ensure that the diagnosis is correct, in order to avoid the inappropriate use of therapies such as inhaled corticosteroids. After exclusion of other diagnoses, if a pre-school child is thought to have asthma, difficult or otherwise, the corollary is, what sort of asthma? Is it a syndrome with airway inflammation susceptible to treatment, or one in which there is no inflammation and time alone will result in resolution of symptoms? Probably the most common mistake in this age group is to fail to recognise the latter and institute ever more aggressive and useless therapies. An approach to excluding other diagnoses, appropriate investigations to elicit the presence of airway inflammation and suggestions for subsequent management have been detailed in this review.

General principles of asthma management: environmental control

Environmental control is one of the major goals of asthma management. House dust mite environmental control and the reduction of other indoor environmental allergen triggers, such as animal dander, cockroaches, and mold spores, are important for individuals with asthma. Patients who have sensitivities to the allergens they produce should receive advice on environmental control reduction measures to prevent asthma symptoms. Nurses are in a key position to make proper environmental control recommendations to patients.