Asthma and allergy avoidance knowledge and behavior in postpartum women

A comprehensive survey analysis focusing on the effect of living literacy on residential environment and health recognition under COVID-19 in Japan

Appropriate knowledge and actions of residents in housing are expected to reduce health effects, defined as "living literacy." With the spread of COVID-19 and the diversification of lifestyles, a quantitative evaluation of a comprehensive model that includes living literacy in the housing environment is required. In this study, the author conducted two web-based surveys of approximately 2000 different households in Japan during the summer of 2020 and winter of 2021, and a statistical analysis based on the survey results. As a result, ventilation by opening windows was observed as a new resident behavior trend under COVID-19. In addition, structural equation modeling using the survey samples confirmed the certain relationship between living literacy and subjective evaluation of the indoor environment and health effects in both periods.

Knowledge of their own allergic sensitizations in asthmatic patients and its impact on the level of asthma control

BACKGROUND

Asthma guidelines recommend the adoption of allergen avoidance measures (AAM). To do so, patients need to know their own allergies. However, this degree of knowledge has not yet been assessed. The aims of this study were to determine, in allergic asthma patients: i)the degree of knowledge of their own allergic sensitizations; ii)the percentage of those who knew all their allergies and, in addition, adopted AAM against all of them, and iii)the possible impact of this degree of knowledge on the level of asthma control.

PATIENTS AND METHODS

Descriptive, prospective and multicentre study, including 147patients from 9 Respiratory Medicine outpatient clinics. After confirming the previous allergic asthma diagnosis, a questionnaire was completed. It included asthma control and severity levels, results of previous allergy tests, and the description and number of allergic sensitizations known by the patients and AAM followed.

RESULTS

Only 72 (49%) patients knew all their allergic sensitizations and only 48 (33%) were also following AAM against all the allergens to which they were allergic. No relationship was established between the degree of knowledge of their own allergies and the level of asthma control (P=.544).

CONCLUSIONS

Overall knowledge about the allergic nature of their disease among asthmatic patients attending Spanish Respiratory Medicine Departments is inadequate. Furthermore, a higher degree of knowledge of their allergies does not seem to lead, by itself, to better asthma control. Both findings seem to question the effectiveness of current educational strategies in this field and consequently, they should be revised.

Possible reasons for lack of effect of allergen avoidance in atopy-prone infants and sensitive asthmatic patients

The basic paradigm that allergen exposure produces atopic sensitization, and that continued exposure leads to clinical asthma throughout the development of airway inflammation and bronchial hyperreactivity has been challenged. However, because it was observed that epidemiological evidence suggests that around 40% of asthma cases are attributable to atopy (even using restrictive criteria), the obvious corollary is that if allergen avoidance begins before the onset of sensitization (primary prevention), then it should be associated with a reduced number of new cases of the disease. However, there are conflicting results regarding the effect of allergen avoidance on primary prevention of atopic sensitization and asthma onset. Instead, more uniform and positive results are available from secondary prevention studies. Secondary prevention obviously is an attractive opportunity for pediatricians who may recognize the patients who might benefit from these interventions simply by screening for food allergy in young children with atopic dermatitis. The conflicting results of tertiary prevention are most frequently observed in adult patients and sometimes result from incomplete avoidance of allergens responsible for the sensitization.

Environmental prevention in atopic eczema dermatitis syndrome (AEDS) and asthma: avoidance of indoor allergens

Indoor allergens represent an important precipitating factor for both asthma and atopic eczema dermatitis syndromes (AEDS). There is also accumulating evidence that sensitization to those allergens is associated with the onset of atopic disorders. Patients with AEDS present aeroallergen-specific T-cell responses associated with worsening of symptoms when exposed to specific aeroallergens. Furthermore, application of indoor allergens to the skin of patient with AEDS induces a local eczematous response in one-third of these patients. Exposure to high concentrations of mite allergens in early infancy have been demonstrated to be a risk factor for developing atopic dermatitis during the first 3 years of life. Moreover, a clear dose-response relationship has been documented between mite exposure and disease activity. Primary prevention of AEDS by avoiding indoor allergen exposure has been proved to be effective only when allergenic foods have also been avoided. Mite allergen avoidance in infants with AEDS and food allergy may however, prevent mite sensitization and the onset of asthma. Indoor allergen avoidance has been demonstrated to be effective in the majority of studies performed in patients with established AEDS. Negative results may be explained either by individual susceptibility variation, by long duration of disease with the consequent irreversible pathological changes in the target tissue or by exposure to allergens outside the house. Education of the patients and public consciousness of the problems are crucial for the efficacy of indoor allergen avoidance in allergic diseases.

Addressing the prevalence of respiratory allergy in the home environment

Respiratory allergy prevalence has always depended both on genetic predisposition and specific environmental allergenic stimulation that leads to sensitization and eventual symptomatic disease. Changes brought about by modern technology that have afforded a higher quality of life have also accidentally increased the levels of many respirable and ingestible allergens in the environment. In many cases these higher levels of exposure have exceeded individual thresholds, resulting in the phenotypic expression of allergy in many individuals who were previously asymptomatic even though they were genotypically predisposed to developing allergies. Prevalence can be decreased only if susceptible populations are identified as early as possible through careful family history taking and appropriate testing for sensitivity and if exposure to selected allergens is controlled.

Environmental exposure reduction in high-risk newborns: where do we start?

BACKGROUND

When analyzing the effect of environmental exposure reduction measures on asthma in high-risk children, one must know how far asthmatic families already have applied such measures, because this would affect the effectiveness and efficiency of interventions aimed at reducing environmental exposure.

OBJECTIVE

To describe the room for improvement by asthmatic families in mite, pet, and food allergen reducing measures and in parental passive smoking and to determine the resulting levels of mite and pet allergens by the applied sanitation measures.

METHODS

Data were sampled by observation, weekly diary entries, and questionnaire when the infant was 6 months old and 1 year old. Dust samples were collected by vacuuming the living room floor and the parental and infant mattresses. Multiple logistic regression analyses were applied with the use of mattress encasing, having a smooth floor covering, having pets, exclusive breast-feeding and/or hypoallergenic formula during the infant's first 6 months, and passive smoking as the dependent variables.

RESULTS

Frequencies of applied measures were as follows: having a smooth floor covering, 36%; daily house cleaning, 27%; use of parental and infant antimite mattress encasings, 13% and 9%, respectively; keeping no pets, 66%; no cow's milk-based regular formula, 13%; no solid foods in the first 6 months of life, 28%; and abstinence of smoking by the mother prenatally, 89%; by the mother postnatally, 85%; and by her partner, 76%. Having a smooth floor covering and daily cleaning but not use of antimite mattress encasings resulted in significantly lower mite and pet allergen levels.

CONCLUSIONS

There is (still) enough room for improvement to reduce exposure to inhalant and food allergens, especially by application of mattress encasings, exclusive breast-feeding and/or hypoallergenic formula feeding, and postponing the time until first solids are given.

Allergy markers in adults in relation to the timing of pet exposure: the EGEA study

BACKGROUND

Studies suggest that early childhood exposure to pets may protect from the development of atopy, but limited information is available on adults. The association of allergy markers in adulthood with current and childhood exposure to pets was studied considering retrospectively the window of exposure.

METHODS

Immunoglobulin E (IgE), skin prick tests (SPT), eosinophils were related to exposure to pets in 187 adult asthmatic cases and 243 controls from the Epidemiological Study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy (EGEA) study. Analyses were redone after exclusion of subjects who removed pets or experienced symptoms to animals to take into account selection in that retrospective study.

RESULTS

In asthmatic cases, current exposure to pets was unrelated to SPT positivity (+), whereas childhood exposure was significantly related to less SPT+ to any allergen, and to cat in particular, with an association restricted to those exposed before 2 years of age [OR = 0.30 (CI 0.12-0.76)]. Considering the relative timing of exposure in relation to asthma onset showed that the protective effect of exposure to pets occurs for pet exposure starting before asthma onset [OR for SPT+ = 0.19 (CI 0.08-0.48)].

CONCLUSION

Results support the hypothesis that exposure to pets in early life, and in particular before asthma onset, may protect against allergen sensitization in adulthood.

Primary prevention of asthma

There has been a dramatic increase in the prevalence of asthma over the last quarter century, particularly in the industrialized world. Although our understanding of asthma continues to improve, there is no cure for the disease. Primary prevention of asthma is the focus of this review. Asthma is a disease with multiple gene-environment interactions. Candidate genes for asthma are considered, and potential interaction between one of those genes, CD14, and an environmental factor, endotoxin, is reviewed as it relates to the hygiene hypothesis. Environmental risk factors for asthma including allergens, pollutants, infectious factors, and dietary modifications are considered, particularly their potential for primary prevention of asthma. Ongoing cohort studies including the Canadian Allergy and Asthma Prevention Study, the Manchester Allergy and Asthma Study, the Children's Asthma Prevention Study from Australia, and the Prevention and Incidence of Asthma and Mite Allergy Study from the Netherlands are briefly reviewed. A more definitive understanding of genetic background and environmental triggers and their interactions is required before any specific approach to the primary prevention of asthma can be championed aggressively.

Are children at high familial risk of developing allergy born into a low risk environment? The PIAMA Birth Cohort Study. Prevention and Incidence of Asthma and Mite Allergy

BACKGROUND

A family history of allergy, reflecting genetic risk factors, increases the risk of developing allergic diseases, but environmental factors, especially those present in early life, also contribute to the actual development of allergic phenomena.

OBJECTIVE

To identify differences in lifestyle between allergic and non-allergic parents, which may influence the prevalence of environmental risk factors in their homes.

METHODS

Data were collected in a Dutch birth cohort study by postal questionnaire about 2 months before and 3 months after the birth of the child.

RESULTS

Of the 3147 infants in the study 1910 (61%) had two non-allergic parents, of 315 infants (10%) only the mother was allergic, of 787 infants (25%) only the father was allergic and 135 (4%) infants had two allergic parents. If both parents were allergic, 53% reported that allergy was taken into consideration when they furnished their home and significantly more of their homes were free of cats and free of cigarette smoke; adjusted odds ratio's for two allergic parents vs. two non-allergic parents were 0.30 (confidence interval (CI) 0.17-0.50) for the presence of cats and 0.46 (CI 0.27-0.75) for smoking in the home. Parental allergy was also associated with having a smooth floor in the baby's bedroom and with postponement of the introduction of fruits and vegetables until the age of 26 weeks. The presence of dogs at home, the prevalence of mothers' smoking during pregnancy and the decision to breast feed were unrelated to parental allergy.

CONCLUSION

We conclude that studies on the relationship between allergy in parents and allergy in their offspring should always consider the home environment as a potential confounder. For allergy prevention our results imply that among allergic parents there is awareness and willingness to take measures that reduce exposure to indoor allergens.

Asthma and the home environment of low-income urban children: preliminary findings from the Seattle-King County healthy homes project

OBJECTIVES

Childhood asthma is a growing public health concern in low-income urban communities. Indoor exposure to asthma triggers has emerged as an important cause of asthma exacerbations. We describe indoor environmental conditions related to asthma triggers among a low-income urban population in Seattle/King County, Washington, as well as caregiver knowledge and resources related to control of these triggers.

METHODS

Data are obtained from in-person, structured, closed-end interviews with the caretakers of children aged 4-12 years with persistent asthma living in households with incomes less than 200% of poverty. Additional information is collected during a home inspection. The children and their caregivers are participants in the ongoing Seattle-King County Healthy Homes Project, a randomized controlled trial of an intervention to empower low-income families to reduce exposure to indoor asthma triggers. We report findings on the conditions of the homes prior to this intervention among the first 112 enrolled households.

RESULTS

A smoker was present in 37.5% of homes. Mold was visible in 26.8% of homes, water damage was present in 18.6% of homes, and damp conditions occurred in 64.8% of households, while 39.6% of caregivers were aware that excessive moisture can increase exposures to allergens. Dust-trapping reservoirs were common; 76.8% of children's bedrooms had carpeting. Cockroach infestation in the past 3 months was reported by 23.4% of caregivers, while 57.1% were unaware of the association of roaches and asthma. Only 19.8% of the children had allergy-control mattress covers.

CONCLUSIONS

Many low-income urban children with asthma in King County live in indoor environments that place them at substantial risk of ongoing exposure to asthma triggers. Substandard housing and lack of resources often underlie these exposures. Initiatives involving health educators, outreach workers, medical providers, health care insurers, housing agencies, and elected officials are needed to reduce these exposures.