Dampness, mould, onset and remission of adult respiratory symptoms, asthma and rhinitis

Socioeconomic patterns in indoor environment in Denmark: cross-sectional studies from 2000 and 2021

OBJECTIVES

To examine changes and socioeconomic patterns in indicators of a poor indoor environment in 2000 and 2021.

STUDY DESIGN

Cross-sectional data from the Danish Health and Morbidity Survey in 2000 and 2021.

METHODS

The study included 27,068 participants. Indicators of indoor environment (annoyances from mould, temperature, draught, traffic and neighbour noise, and presence of water damage) were obtained from questionnaires (2021) and partly by interview (2000). Socioeconomic status included home ownership, educational level, and household income. The degree of social inequality in the indoor environment was estimated using the concentration index of inequality.

RESULTS

The prevalence of annoyances due to draught, temperature, and noise increased significantly from 2000 to 2021 (e.g., temperature 5.9%-25.1%, odds ratio (OR) 6.72, 95% confidence interval (CI) 6.12-7.38), whereas the prevalence of water damage decreased (17.7%-13.8%, OR 0.85, 95% CI 0.76-0.96). No difference was seen in annoyances due to mould (3.1% in 2000 and 2.5% in 2021, OR 0.90, 95% CI 0.69-1.17). Social inequality was present for thermal conditions, annoyances due to noise and presence of water damage when assessed by income but not by educational level. Conditions were more prevalent among individuals with low income in both 2000 and 2021.

CONCLUSIONS

The proportion of individuals reporting a poor indoor environment due to thermal conditions and noise increased in the period 2000-2021. Social inequality was observed in all indicators of a poor indoor environment for household income, whereas the inequality was less pronounced when assessed by educational level.

Is there still a social gradient in respiratory symptoms? A population-based Nordic EpiLung-study

BACKGROUND

Respiratory symptoms are a common public health issue that can partly be attributed to preventable risk factors, such as tobacco smoking and occupational exposure, which are more common in individuals with lower socioeconomic status.

OBJECTIVE

Our aim was to evaluate the social gradient in respiratory symptoms in Nordic countries.

METHODS

This study included participants aged 30-65 years from five cross-sectional population-based questionnaire surveys in 2016 in Finland and Sweden (N = 25,423) and in 2017-2019 in Norway (N = 27,107). Occupational skill levels 1 and 2 (occupations requiring compulsory education) were combined and compared to skill levels 3 and 4 (occupations requiring upper secondary and tertiary education). Meta-analysis was conducted to obtain pooled age- and sex adjusted odds ratios (aORs) of associations between occupational skill and the respiratory symptoms including recurrent wheeze, dyspnoea, and productive cough.

RESULTS

In the meta-analysis, recurrent wheeze, dyspnoea, and productive cough showed a social gradient. The participants with occupational skill 1 and 2 had higher risk for recurrent wheeze (aOR 1.78, 95% CI 1.34-2.22) and dyspnoea (aOR 1.59, 95% CI 1.29-1.90) compared to occupational skill 3 and 4 in Sweden and Finland. Similarly increased risk was observed for combined assessment of dyspnoea and wheeze (aOR 1.05, 95% CI 1.03-1.07) in Norway. In a meta-analysis including all three countries, the aOR for productive cough was 1.31 95% CI 1.07-1.56.

CONCLUSIONS

Occupations with lower, compared to higher, skill levels were associated with an increased risk of recurrent wheeze, dyspnoea, and productive cough.

Outdoor Alternaria and Cladosporium spores and acute asthma

BACKGROUND

Outdoor Alternaria and Cladosporium spores are ubiquitous. Few studies have assessed their impact on asthma hospitalizations providing conflicting results, mainly focused on vulnerable paediatric populations. We aimed to study the impact of outdoor Alternaria and Cladosporium concentrations on acute hospitalizations in the Capital Region of Denmark.

METHODS

This is a bi-directional case-crossover study with 26 years of national registry data at individual level on acute asthma hospitalizations and daily average data on Alternaria and Cladosporium, pollen (Artemisia, Poaceae), maximal temperature, and air pollution. Conditional logistic regression models were applied to assess the associations. Concentration quartiles at lag 0 were used for categorizing the exposure.

RESULTS

For lags 0-2, the odds of hospitalization were significantly higher for both Alternaria and Cladosporium at concentration quartile 2-4 compared with quartile 1. When stratified for age and sex, odds of hospitalization at Alternaria quartiles 2-4 were significantly higher in males below 40 years at lag 0-2, and at lag 0 in females (18-30 years), while quartiles 2-4 of Cladosporium concentrations were associated with significantly higher odds in boys (0-17 years) at lag 1-3, males (18-39 years) at lag 0-1, females (18-39 years) at lag 1-2, males (40-64 years) at lag 0-2, females (40-64 years) at lag 0 and 2, in seniors (65+ years) male at lag 1-2 and female at lag 0-1. The effect of Alternaria varied significantly depending on the level of Cladosporium (p < .0001).

CONCLUSION

Ambient Alternaria and Cladosporium spores can induce asthma hospitalizations. Males are more susceptible to both genera. Males and females under age 40 years are more susceptible to Alternaria.

Rhinitis in Japanese students - associations with window pane condensation, recent indoor painting, wooden home and dog allergen at school

We studied risk factors for rhinitis in Japanese homes and schools. A questionnaire was sent to students in four schools (12-15 y age), 1048 (99.2%) participated. Crowdedness and furry pet allergens were measured in their classrooms. Household environment data was collected by a questionnaire. Risk factors were identified by multi-level logistic regression with mutual adjustment. The prevalence of current rhinitis was 60.3%, current rhinoconjunctivitis 24.4% and weekly rhinitis 29.5%. Window condensation (AORs1.69-1.90) and indoor painting (AORs1.72-1.76) at home were associated with rhinitis. The association between painting and rhinitis was stronger in girls (interaction p = 0.002) and in wooden homes (interaction p = 0.05). Dog allergen (Can f 1) in classroom air was associated with rhinitis (p = 0.04). In conclusion, window pane condensation and indoor painting can be household risk factors for rhinitis and dog allergen may be a risk factor in Japanese schools. Girls can be more sensitive to emissions from indoor paint than boys.

Ambient particulate matter associates with asthma in high altitude region: A population-based study

Background

Exposure to particulate matter (PM) has been a major public health threat, but the potentially differential effects on asthma of PM remain largely unknown in high altitude settings. We evaluated the effects of ambient PM on asthma in high altitude settings.

Methods

The study recruited a representative sample from high altitude settings using a multistage stratified sampling procedure. Asthma was defined by a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. The annual mean PM_2.5 and PM₁₀ concentrations were calculated for each grid cell at 1-km spatial resolution based on the geographical coordinates.

Results

We analyzed data for participants (mean age 39.1 years, 51.4% female) and 183 (3.7%, 95% confidence interval (CI): 3.2-4.2) of the participants had asthma. Prevalence was higher in women (4.3%, 95% CI 3.5-5.1) than in men (3.1%, 2.4-3.8) and increasing with higher concentration of PM exposures. For an interquartile range (IQR) difference (8.77 μg/m³) in PM_2.5 exposure, the adjusted odds ratio (OR) was 1.64 (95% CI 1.46-1.83, P < 0.001) for risk of asthma. For PM₁₀, there was evidence for an association with risk of asthma (OR 2.34, 95% CI: 1.75-3.15, P < 0.001 per IQR of 43.26 μg/m³). Further analyses showed that household mold or damp exposure may aggravate PM exposure associated risks of asthma.

Conclusions

This study identified that PM exposure could be a dominate environmental risk factor for asthma but largely unconsidered in the high-altitude areas. The association between PM exposure and asthma should be of interest for planners of national policies and encourage programs for prevention of asthma in residents living at high altitudes.

Exposure-response relationship of residential dampness and mold damage with severe lower respiratory tract infections among under-five children in Nigeria

Previous epidemiological studies demonstrated an increased risk of respiratory health effects in children and adults exposed to dampness or mold. This study investigated associations of quantitative indicators of indoor dampness and mold exposure with severe lower respiratory tract infections (LRTI) among children aged 1-59 months in Ibadan, Nigeria.

Methods

In-home visits were conducted among 178 children hospitalized with LRTI matched by age (±3 months), sex, and geographical location with 180 community-based children without LRTI. Trained study staff evaluated the indoor environment using a standardized home walkthrough checklist and measured visible dampness and mold damage. Damp-moldy Index (DMI) was also estimated to quantify the level of exposure. Exposure-response relationships of dampness and mold exposure with severe LRTI were assessed using multivariable restricted cubic spline regression models adjusting for relevant child, housing, and environmental characteristics.

Results

Severe LRTI cases were more often male than female (61.8%), and the overall mean (SD) age was 7.3 (1.35) months. Children exposed to dampness <0.3 m² (odds ratio [OR] = 2.11; 95% confidence interval [CI] = 1.05, 4.36), and between 0.3 and 1.0 m² (OR = 2.34; 95% CI = 1.01, 7.32), had a higher odds of severe LRTI compared with children not exposed to dampness. The restricted cubic spline showed a linear exposure-response association between severe LRTI and residential dampness (P < 0.001) but a nonlinear relationship with DMI (P = 0.01).

Conclusions

Residential dampness and DMI were exposure-dependently associated with higher odds of severe LRTI among under-five children. If observed relationships were causal, public health intervention strategies targeted at reducing residential dampness are critically important to mitigate the burden of severe LRTI among under-five children.

Volatile organic compounds (VOC) in homes associated with asthma and lung function among adults in Northern Europe

Associations between measured specific VOC reported to be associated with dampness and microbial growth in dwellings and asthma, lung function were investigated in 159 adults (one adult/home) from three North European cities (Reykjavik, Uppsala and Tartu). Spirometry was performed and forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁) and FEV₁/FVC were measured. Among 159 participants, 58% were females, 24.5% atopics, 25.8% current smokers and 41% reported dampness or mold at home. Dimethyl disulphide (p = 0.004), ethyl isobutyrate (p = 0.021) and ethyl 2-methylbutyrate (p = 0.035) were associated with asthma. Isobutanol (p = 0.043), 3-methyl-1-butanol (p = 0.020), 2-hexanone (p = 0.033), 1-octen-3-ol (p = 0.027), 2-methyl-1-butanol (p = 0.022) and 2-ethyl-1-hexanol (p = 0.045) were associated with lower FEV₁. Isobutanol (p = 0.004), 3-methyl-1-butanol (p = 0.001), 2-heptanone (p = 0.047) and 2-methyl-1-butanol (p = 0.002) were associated with lower FEV₁/FVC. The association between dimethyl disulphide and asthma was more pronounced in females (p for interaction 0.099). The association between 1-butanol and lower FEV₁ was more pronounced in males (p for interaction 0.046). The associations between 3-octanone (p for interaction 0.064), 2-ethyl-1-hexanol (p for interaction 0.049) and lower FEV₁, and between 2-heptanone (p for interaction 0.021), 3-octanone (p for interaction 0.008) and lower FEV₁/FVC were stronger in homes with dampness/mold. Factor analysis identified one VOC factor related to asthma and two VOC factors related to lower lung function. Increased air concentrations of 2-heptanone, ethyl 2-methylbutyrate and ethyl isobutyrate were related to prescence of certain mold species (Aspergillus sp., Cladosporum sp. and Penicillium sp.) or building dampness. Some VOC were associated with type of dwelling, building age and pet keeping. In conclusion, some VOC reported to be associated with dampness and microbial growth can be associated with asthma and lower lung function in adults. Associations between these VOC and respiratory illness can be stronger in homes with dampness/mold. There can be gender differences in respiratory health effects when exposed to indoor VOC.

Asthma, allergic rhinitis and atopic dermatitis in association with home environment - The RHINE study

We studied home environment exposures in relation to asthma, allergic rhinitis and atopic dermatitis among offspring of participants (parents) in the Respiratory Health in Northern Europe (RHINE) study (age ≤ 30 y). Totally 17,881 offspring from Iceland, Norway, Sweden, Denmark and Estonia were included. Home environment exposures, including dampness and mold, type of dwelling, construction year and indoor painting were registered through a questionnaire answered by parents in the first follow up (RHINE II). The parents reported ten years later with in the frame of RHINE III offspring's birth year and offspring's asthma, allergic rhinitis, atopic dermatitis. They also reported dampness and mold at home from RHINE II to RHINE III. The prevalence of offspring's asthma before 10 y, asthma after 10 y, allergic rhinitis at any age and atopic dermatitis at any age were 9.7 %, 4.3 %, 15.6 % and 17.3 %, respectively. Asthma before 10 y was related to any indoor painting at RHINE II (OR = 1.14, 95%CI (1.02, 1.29)). Asthma after 10 y was associated with dampness/mold at home (OR = 1.33-1.62) and living in the newest buildings (constructed in 1986-2001) (OR = 1.30, 95%CI (1.02, 1.66)). Allergic rhinitis was associated with living in newer buildings (constructed in 1961-2001) (OR = 1.16-1.24). Atopic dermatitis was associated with visible mold (OR = 1.35, 95%CI(1.12, 1.62)), dampness/mold at home (OR = 1.18-1.38), living in apartments (OR = 1.22, 95%CI(1.10, 1.35)) and living in newer buildings (constructed in 1961-2001) (OR = 1.14-1.25). There were dose-response effects of dampness and mold on offspring's asthma after 10 y and atopic dermatitis (20 years exposure vs. 10 years exposure). Older offspring had increased risk of developing asthma after 10 y and atopic dermatitis. In conclusion, home dampness and mold, living in apartments, living in newer buildings and indoor painting were associated with offspring's asthma or allergic diseases. Stronger health effects were found among offspring with prolonged exposure of dampness/mold.

Retrofitting home insulation reduces incidence and severity of chronic respiratory disease

To assess whether retrofitting home insulation can reduce the risk of respiratory disease incidence and exacerbation, a retrospective cohort study was undertaken using linked data from a national intervention program. The study population was made up of 1 004 795 residents from 205 001 New Zealand houses that received an insulation subsidy though a national Energy Efficiency and Conservation Authority program. A difference-in-difference model compared changes in the number of prescriptions dispensed for respiratory illness post- insulation to a control population over the same timeframe. New prescribing of chronic respiratory disease medication at follow-up was used to compare incidence risk ratios between intervention and control groups. Chronic respiratory disease incidence was significantly lower in the intervention group at follow-up: odds ratio 0.90 (95% CI: 0.86-0.94). There was also a 4% reduction in medication dispensed for treating exacerbations of chronic respiratory disease symptoms in the intervention group compared with the control group: relative rate ratio (RRR) 0.96 (95% CI: 0.96-0.97). There was no change in medication dispensed to prevent symptoms of chronic respiratory disease RRR: 1,00 (95% CI: 0.99-1.00). These findings support home insulation interventions as a means of improving respiratory health outcomes.

Retrofitting home insulation reduces incidence and severity of chronic respiratory disease

To assess whether retrofitting home insulation can reduce the risk of respiratory disease incidence and exacerbation, a retrospective cohort study was undertaken using linked data from a national intervention program. The study population was made up of 1 004 795 residents from 205 001 New Zealand houses that received an insulation subsidy though a national Energy Efficiency and Conservation Authority program. A difference-in-difference model compared changes in the number of prescriptions dispensed for respiratory illness post- insulation to a control population over the same timeframe. New prescribing of chronic respiratory disease medication at follow-up was used to compare incidence risk ratios between intervention and control groups. Chronic respiratory disease incidence was significantly lower in the intervention group at follow-up: odds ratio 0.90 (95% CI: 0.86-0.94). There was also a 4% reduction in medication dispensed for treating exacerbations of chronic respiratory disease symptoms in the intervention group compared with the control group: relative rate ratio (RRR) 0.96 (95% CI: 0.96-0.97). There was no change in medication dispensed to prevent symptoms of chronic respiratory disease RRR: 1,00 (95% CI: 0.99-1.00). These findings support home insulation interventions as a means of improving respiratory health outcomes.

A Mixed-Methods Assessment of Residential Housing Tenants’ Concerns about Property Habitability and the Implementation of Habitability Laws in Southern Nevada

Housing is a key health determinant. Habitability laws set minimum standards for adequate housing. However, accessing them to ensure adequate housing may be a challenge for many tenants. This paper explores the need for rental housing policy that would better support adequate and safe housing, particularly for low-income renters. A mixed-methods approach assessed residential tenant habitability concerns in Clark County, Nevada, through calls relayed to the Clark County Landlord–Tenant Hotline (CCLTH). Of the 2865 calls, 74.3% were from ZIP codes that were 80% of the median income and below. There was a significant relationship between the ZIP code-level income and the reporting of at least one essential habitability concern. Of the 266 participants that responded to a follow-up call, 34.6% reported that their complaint was resolved and there was no association between resolution and income. Qualitative data analysis from phone interviews revealed two central themes: (1) resources to navigate landlord–tenant laws are limiting and (2) housing policies need to be strengthened to help tenants and keep people housed. Understanding tenant concerns regarding substandard housing and related inequities can help inform rental housing policy and its implementation to promote healthy homes and improve health outcomes for communities burdened by poor rental housing conditions.

The risk of respiratory tract infections and antibiotic use in a general population and among people with asthma

Aim

The aim of this study was to investigate occupational, environmental, early life and other risk factors associated with respiratory infections and antibiotics use in a general population and among asthmatic individuals.

Method

This study included 15 842 participants of the Respiratory Health in Northern Europe (RHINE) study aged 25–54 years from five Nordic countries, who answered a questionnaire covering respiratory outcomes, exposures, demographic characteristics and numbers of infections and courses of antibiotics in the last 12 months. Multiple logistic regression with and without adjustment for age, sex, smoking status, body mass index and centre were used to study the risk of infection and antibiotics in relation to asthma, and also the association between infection and antibiotics and occupations.

Results

In the whole population, 11.6% reported having three or more respiratory infections, and 14.7% had used antibiotics because of respiratory tract infections within the last year. Asthmatic participants reported tripled odds for such infections (adjusted OR 2.98, 95% CI 2.53–3.52) and antibiotics use (adjusted OR 3.67, 95% CI 3.18–4.24) as compared to non-asthmatic participants. Both in the general and the asthmatic population, female sex, obesity and exposure to building dampness were associated with respiratory infections. Female sex and current smoking and living in Tartu were associated with antibiotic use. The use of antibiotics was doubled in people hospitalised for severe respiratory infection in childhood.

Conclusion

In this study we identified several factors associated with increased respiratory infections and use of antibiotics in a general population and among asthmatic individuals. The frequency of respiratory infections and subsequent antibiotic treatment were increased among those with asthma.

The main findings of this study are that asthmatics reported three times higher odds for respiratory tract infections and more than three times higher odds for subsequent antibiotics than subjects without asthmahttps://bit.ly/3hwsH67

Multiple Chemical Sensitivity in Patients Exposed to Moisture Damage at Work and in General Working-Age Population-The SAMDAW Study

A considerable proportion of patients having respiratory tract or voice symptoms associated with workplace moisture damage (MD) could have multiple chemical sensitivity (MCS). MCS is characterized by symptoms of different organ systems in association with low-level chemical exposure. The objective of this study was to assess the prevalence of MCS among patients referred to secondary health care because of respiratory or voice symptoms associated with workplace MD compared to the general working-age population. Using three subscales of the QEESI© questionnaire, we assessed MCS in the study patients and 1500 controls in the same district randomly selected from the Finnish Population Information System. Study patients had significantly more often high scores in chemical intolerance (39% vs. 23%, p = 0.001), symptom severity (60% vs. 27%, p < 0.001), and life impact subscales (53% vs. 20%, p < 0.001). Asthma, chronic rhinosinusitis, laryngeal problems, and atopy were not associated with the presence of MCS. MCS is common among patients referred to secondary health care with respiratory tract and/or voice symptoms associated with workplace MD, and it considerably affects their everyday life. MCS should be considered as a possible explanatory factor for MD-associated symptoms.

Transcriptomic Profiling of Adult-Onset Asthma Related to Damp and Moldy Buildings and Idiopathic Environmental Intolerance

A subset of adult-onset asthma patients attribute their symptoms to damp and moldy buildings. Symptoms of idiopathic environmental intolerance (IEI) may resemble asthma and these two entities overlap. We aimed to evaluate if a distinct clinical subtype of asthma related to damp and moldy buildings can be identified, to unravel its corresponding pathomechanistic gene signatures, and to investigate potential molecular similarities with IEI. Fifty female adult-onset asthma patients were categorized based on exposure to building dampness and molds during disease initiation. IEI patients (n = 17) and healthy subjects (n = 21) were also included yielding 88 study subjects. IEI was scored with the Quick Environmental Exposure and Sensitivity Inventory (QEESI) questionnaire. Inflammation was evaluated by blood cell type profiling and cytokine measurements. Disease mechanisms were investigated via gene set variation analysis of RNA from nasal biopsies and peripheral blood mononuclear cells. Nasal biopsy gene expression and plasma cytokine profiles suggested airway and systemic inflammation in asthma without exposure to dampness (AND). Similar evidence of inflammation was absent in patients with dampness-and-mold-related asthma (AAD). Gene expression signatures revealed a greater degree of similarity between IEI and dampness-related asthma than between IEI patients and asthma not associated to dampness and mold. Blood cell transcriptome of IEI subjects showed strong suppression of immune cell activation, migration, and movement. QEESI scores correlated to blood cell gene expression of all study subjects. Transcriptomic analysis revealed clear pathomechanisms for AND but not AAD patients. Furthermore, we found a distinct molecular pathological profile in nasal and blood immune cells of IEI subjects, including several differentially expressed genes that were also identified in AAD samples, suggesting IEI-type mechanisms.

Clinical Findings among Patients with Respiratory Symptoms Related to Moisture Damage Exposure at the Workplace-The SAMDAW Study

BACKGROUND

Respiratory tract symptoms are associated with workplace moisture damage (MD). The focus of this observational clinical study was patients with workplace MD-associated symptoms, to evaluate the usefulness of different clinical tests in diagnostics in secondary healthcare with a special interest in improving the differential diagnostics between asthma and laryngeal dysfunction.

METHODS

In patients referred because of workplace MD-associated respiratory tract symptoms, we sought to systematically assess a wide variety of clinical findings.

RESULTS

New-onset asthma was diagnosed in 30% of the study patients. Laryngeal dysfunction was found in 28% and organic laryngeal changes in 22% of the patients, and these were common among patients both with and without asthma. Most of the patients (85%) reported a runny or stuffy nose, and 11% of them had chronic rhinosinusitis. Atopy was equally as common as in the general population.

CONCLUSIONS

As laryngeal changes were rather common, we recommend proper differential diagnostics with lung function testing and investigations of the larynx and its functioning, when necessary, in cases of prolonged workplace MD-associated symptoms. Chronic rhinosinusitis among these patients was not uncommon. Based on this study, allergy testing should not play a major role in the examination of these patients.

Exposure to environmental phenols and parabens, and relation to body mass index, eczema and respiratory outcomes in the Norwegian RHINESSA study

BACKGROUND

Many phenols and parabens are applied in cosmetics, pharmaceuticals and food, to prevent growth of bacteria and fungi. Whether these chemicals affect inflammatory diseases like allergies and overweight is largely unexplored. We aimed to assess the associations of use of personal care products with urine biomarkers levels of phenols and paraben exposure, and whether urine levels (reflecting body burden of this chemical exposures) are associated with eczema, rhinitis, asthma, specific IgE and body mass index.

METHODS

Demographics, clinical variables, and self-report of personal care products use along with urine samples were collected concurrently from 496 adults (48% females, median age: 28 years) and 90 adolescents (10-17 years of age) from the RHINESSA study in Bergen, Norway. Urine biomarkers of triclosan (TCS), triclocarban (TCC), parabens and benzophenone-3, bisphenols and dichlorophenols (DCP) were quantified by mass spectrometry.

RESULTS

Detection of the urine biomarkers varied according to chemical type and demographics. TCC was detected in 5% of adults and in 45% of adolescents, while propyl (PPB) and methyl (MPB) parabens were detected in 95% of adults and in 94% (PPB) and 99% (MPB) of adolescents. Women had higher median urine concentrations of phenolic chemicals and reported a higher frequency of use of personal care products than men. Urine concentration of MPB increased in a dose-dependent manner with increased frequency of use of several cosmetic products. Overall, urinary biomarker levels of parabens were lower in those with current eczema. The biomarker concentrations of bisphenol S was higher in participants with positive specific IgE and females with current asthma, but did not differ by eczema or rhinitis status. MPB, ethylparaben (EPB), 2,4-DCP and TCS were inversely related to BMI in adults; interaction by gender were not significant.

CONCLUSIONS

Reported frequency of use of personal care products correlated very well with urine biomarker levels of paraben and phenols. Several chemicals were inversley related to BMI, and lower levels of parabens was observed for participants with current eczema. There is a need for further studies of health effects of chemicals from personal care products, in particular in longitudinally designed studies.

Snoring and environmental exposure: results from the Swedish GA2LEN study

OBJECTIVE

Habitual snoring is associated with fatigue, headaches and low work performance. This cross-sectional study aimed to investigate if snoring is affected by environmental factors such as home dampness and exposure to air pollution.

SETTING

General population sample from four Swedish cities.

PARTICIPANTS

25 848 participants from the Swedish part of the epidemiological Global Asthma and Allergy and European network of excellence study carried out in 2008. The participants completed a postal questionnaire on snoring and, indoor and outdoor environmental exposure as well as potential confounders including smoking, weight, height and educational level.

RESULTS

Of the participants, 4211 (16.3%) were habitual snorers. Habitual snorers reported water damage (8.3% vs 7.0% p<0.0001), floor dampness (4.6% vs 3.8% % p<0.0001) and visible mould (5.2% vs 3.8% p<0.0001) in their homes more often than non-snorers. Habitual snorers stated being annoyed by air pollution more often than non-snorers with habitual snorers reporting being irritated with the air in their residential area to a higher extent (sometimes 16.2% vs 13.9%, and daily 4.6% vs 3.1%) as well as annoyance from traffic fumes (somewhat 19% vs 18.5% and very 5% vs 3.6%) (p<0.0001). These results remained significant after adjustment for age, body mass index, smoking history and educational level.

CONCLUSION

Snoring is more prevalent in subjects reporting home dampness and air pollution. These association should be confirmed in further research using objective measurements and a longitudinal approach.

Asthma Across the Ages: Adults

Asthma is a common disease affecting approximately 300 million people worldwide, across all age ranges. Despite advances in asthma outcomes of the last few decades, there remains room for improvement in asthma management and for patient outcomes, particularly in older patients. The heterogeneity of asthma is now well recognized, and is known to complicate response to treatment and patient behavior and impact health outcomes. Asthma and its heterogeneity change according to age. Asthma affects people differently across the life span. In adults, prevalence is highest among those in middle age; however, mortality is greater in the older age group. In this clinical commentary, we describe how age impacts asthma prevalence and incidence, outcomes, disease expression, and approach to management in adulthood and in older patients.

Asthma and allergic rhinitis among young parents in China in relation to outdoor air pollution, climate and home environment

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM₁₀ and NO₂ were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO₂ and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO₂ and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

A prospective study on the role of smoking, environmental tobacco smoke, indoor painting and living in old or new buildings on asthma, rhinitis and respiratory symptoms

We studied associations between tobacco smoke, home environment and respiratory health in a 10 year follow up of a cohort of 11,506 adults in Northern Europe. Multilevel logistic regression models were applied to estimate onset and remission of symptoms. Current smokers at baseline developed more respiratory symptoms (OR = 1.39-4.43) and rhinitis symptoms (OR = 1.35). Starting smoking during follow up increased the risk of new respiratory symptoms (OR = 1.54-1.97) and quitting smoking decreased the risk (OR = 0.34-0.60). ETS at baseline increased the risk of wheeze (OR = 1.26). Combined ETS at baseline or follow up increased the risk of wheeze (OR = 1.27) and nocturnal cough (OR = 1.22). Wood painting at baseline reduced remission of asthma (OR 95%CI: 0.61, 0.38-0.99). Floor painting at home increased productive cough (OR 95%CI: 1.64, 1.15-2.34) and decreased remission of wheeze (OR 95%CI: 0.63, 0.40-0.996). Indoor painting (OR 95%CI: 1.43, 1.16-1.75) and floor painting (OR 95%CI: 1.77, 1.11-2.82) increased remission of allergic rhinitis. Living in the oldest buildings (constructed before 1960) was associated with higher onset of nocturnal cough and doctor diagnosed asthma. Living in the newest buildings (constructed 1986-2001) was associated with higher onset of nocturnal breathlessness (OR = 1.39) and rhinitis (OR = 1.34). In conclusion, smoking, ETS and painting indoor can be risk factors for respiratory symptoms. Wood painting and floor painting can reduce remission of respiratory symptoms. Smoking can increase rhinitis. Living in older buildings can be a risk factor for nocturnal cough and doctor diagnosed asthma. Living in new buildings can increase nocturnal dyspnoea and rhinitis.

Bioreactivity, Guttation and Agents Influencing Surface Tension of Water Emitted by Actively Growing Indoor Mould Isolates

The secretion of metabolites in guttation droplets by indoor moulds is not well documented. This study demonstrates the guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and guttation of liquid droplets detected in young (<3 weeks old) biomass were absent in old (>6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (<3 weeks old) biomasses were toxic more than 10 times towards mammalian cell lines (PK-15 and MNA) compared to the old dormant, dry biomasses, when calculated per biomass wet weight and per conidial particle. Surfactant activity was emitted in exudates from fresh biomass of T. atroviride, Rhizopus sp. and Stachybotrys sp. Surfactant activity was also provoked by fresh conidia from T. atroviride and Stachybotrys sp. strains. Water repealing substances were emitted by cultures of P. expansum, T. atroviride and C. globosum strains. The metabolic state of the indoor fungal growth may influence emission of liquid soluble bioreactive metabolites into the indoor air.

Observational studies assessing the pharmacological treatment of obstructive lung disease: strengths, challenges and considerations for study design

Randomised controlled trials (RCTs) are the gold standard for evaluating treatment efficacy in patients with obstructive lung disease. However, due to strict inclusion criteria and the conditions required for ascertaining statistical significance, the patients included typically represent as little as 5% of the general obstructive lung disease population. Thus, studies in broader patient populations are becoming increasingly important. These can be randomised effectiveness trials or observational studies providing data on real-world treatment effectiveness and safety data that complement efficacy RCTs. In this review we describe the features associated with the diagnosis of asthma and chronic obstructive pulmonary disease (COPD) in the real-world clinical practice setting. We also discuss how RCTs and observational studies have reported opposing outcomes with several treatments and inhaler devices due to differences in study design and the variations in patients recruited by different study types. Whilst observational studies are not without weaknesses, we outline recently developed tools for defining markers of quality of observational studies. We also examine how observational studies are capable of providing valuable insights into disease mechanisms and management and how they are a vital component of research into obstructive lung disease. As we move into an era of personalised medicine, recent observational studies, such as the NOVEL observational longiTudinal studY (NOVELTY), have the capacity to provide a greater understanding of the value of a personalised healthcare approach in patients in clinical practice by focussing on standardised outcome measures of patient-reported outcomes, physician assessments, airway physiology, and blood and airway biomarkers across both primary and specialist care.

Dampness and mold at home and at work and onset of insomnia symptoms, snoring and excessive daytime sleepiness

AIM

To investigate whether exposure to dampness and mold at home and at work induce sleep disturbances and daytime sleepiness among adults.

MATERIALS AND METHODS

Associations between onset of sleep disturbances and dampness, mold and mold odor at home and at work were investigated in a cohort of 11,318 adults from the population in Iceland, Norway, Sweden, Denmark and Estonia. The participants answered a questionnaire at baseline and 10 years later, with questions on sleep disturbances, including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), insomnia symptoms, snoring and excessive daytime sleepiness (EDS). Multiple logistic regression models were applied to estimate associations adjusting for potential confounders including gender, age, smoking habit at baseline, change of smoking habit from baseline to follow up, BMI at baseline, change of BMI from baseline to follow up, education level at follow up, allergic rhinitis at baseline, doctor diagnosed asthma at baseline and chronic bronchitis at baseline.

RESULTS

Baseline floor dampness, visible mold and mold odor at home increased onset of DIS, DMS, EMA, insomnia symptoms and snoring during follow up (OR 1.29-1.87). Any sign of dampness at baseline increased onset of DIS (OR 1.28, 95%CI 1.06-1.55), DMS (OR 1.17, 95%CI 1.02-1.34) and insomnia symptoms (OR 1.18, 95%CI 1.03-1.36). Dampness at home during follow up increased onset of DIS, DMS, EMA, insomnia symptoms and EDS (OR 1.17-1.36). Dampness at work during follow up increased onset of DIS, EMA, insomnia symptoms and EDS (OR 1.16-1.34). Combined dampness at home and at work during follow up increased the risk of onset of DIS, DMS, EMA, insomnia symptoms and EDS (OR 1.29-1.74).

CONCLUSIONS

Dampness and mold at home and at work can increase the development of insomnia symptoms, snoring and EDS among adults.

Workplace indoor environmental quality and asthma-related outcomes in healthcare workers

BACKGROUND

Asthma-related health outcomes are known to be associated with indoor moisture and renovations. The objective of this study was to estimate the frequency of these indoor environmental quality (IEQ) factors in healthcare facilities and their association with asthma-related outcomes among workers.

METHODS

New York City healthcare workers (n = 2030) were surveyed regarding asthma-related symptoms, and moisture and renovation factors at work and at home during the last 12 months. Questions for workplace moisture addressed water damage (WD), mold growth (MG), and mold odor (MO), while for renovations they addressed painting (P), floor renovations (FR), and wall renovations (WR). Regression models were fit to examine associations between work and home IEQ factors and multiple asthma-related outcomes.

RESULTS

Reports of any moisture (n = 728, 36%) and renovations (n = 1412, 70%) at work were common. Workplace risk factors for asthma-related outcomes included the moisture categories of WD by itself, WD with MO (without MG), and WD with MG and MO, and the renovation category with the three factors P, FR, and WR. Reports of home IEQ factors were less frequent and less likely to be associated with health outcomes. Data analyses suggested that MG and/or MO at work and at home had a synergistic effect on the additive scale with a symptom-based algorithm for bronchial hyperresponsiveness.

CONCLUSIONS

The current study determined that moisture and renovation factors are common in healthcare facilities, potentially putting workers at risk for asthma-related outcomes. More research is needed to confirm these results, especially prospective studies.

Indoor microbiome, environmental characteristics and asthma among junior high school students in Johor Bahru, Malaysia

Indoor microbial diversity and composition are suggested to affect the prevalence and severity of asthma by previous home microbiome studies, but no microbiome-health association study has been conducted in a school environment, especially in tropical countries. In this study, we collected floor dust and environmental characteristics from 21 classrooms, and health data related to asthma symptoms from 309 students, in junior high schools in Johor Bahru, Malaysia. The bacterial and fungal composition was characterized by sequencing 16s rRNA gene and internal transcribed spacer (ITS) region, and the absolute microbial concentration was quantified by qPCR. In total, 326 bacterial and 255 fungal genera were characterized. Five bacterial (Sphingobium, Rhodomicrobium, Shimwellia, Solirubrobacter, Pleurocapsa) and two fungal (Torulaspora and Leptosphaeriaceae) taxa were protective for asthma severity. Two bacterial taxa, Izhakiella and Robinsoniella, were positively associated with asthma severity. Several protective bacterial taxa including Rhodomicrobium, Shimwellia and Sphingobium have been reported as protective microbes in previous studies, whereas other taxa were first time reported. Environmental characteristics, such as age of building, size of textile curtain per room volume, occurrence of cockroaches, concentration of house dust mite allergens transferred from homes by the occupants, were involved in shaping the overall microbial community but not asthma-associated taxa; whereas visible dampness and mold, which did not change the overall microbial community for floor dust, was negatively associated with the concentration of protective bacteria Rhodomicrobium (β = -2.86, p = 0.021) of asthma. The result indicates complex interactions between microbes, environmental characteristics and asthma symptoms. Overall, this is the first indoor microbiome study to characterize the asthma-associated microbes and their environmental determinant in the tropical area, promoting the understanding of microbial exposure and respiratory health in this region.