1
|
Clemente-Suárez VJ, Mielgo-Ayuso J, Ramos-Campo DJ, Beltran-Velasco AI, Martínez-Guardado I, Navarro Jimenez E, Redondo-Flórez L, Yáñez-Sepúlveda R, Tornero-Aguilera JF. Basis of preventive and non-pharmacological interventions in asthma. Front Public Health 2023; 11:1172391. [PMID: 37920579 PMCID: PMC10619920 DOI: 10.3389/fpubh.2023.1172391] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 09/18/2023] [Indexed: 11/04/2023] Open
Abstract
Asthma is one of the most common atopic disorders in all stages of life. Its etiology is likely due to a complex interaction between genetic, environmental, and lifestyle factors. Due to this, different non-pharmacological interventions can be implemented to reduce or alleviate the symptoms caused by this disease. Thus, the present narrative review aimed to analyze the preventive and non-pharmacological interventions such as physical exercise, physiotherapy, nutritional, ergonutritional, and psychological strategies in asthma treatment. To reach these aims, an extensive narrative review was conducted. The databases used were MedLine (PubMed), Cochrane (Wiley), Embase, PsychINFO, and CinAhl. Asthma is an immune-mediated inflammatory condition characterized by increased responsiveness to bronchoconstrictor stimuli. Different factors have been shown to play an important role in the pathogenesis of asthma, however, the treatments used to reduce its incidence are more controversial. Physical activity is focused on the benefits that aerobic training can provide, while physiotherapy interventions recommend breathing exercises to improve the quality of life of patients. Nutritional interventions are targeted on implement diets that prioritize the consumption of fruits and vegetables and supplementation with antioxidants. Psychological interventions have been proposed as an essential non-pharmacological tool to reduce the emotional problems associated with asthma.
Collapse
Affiliation(s)
- Vicente Javier Clemente-Suárez
- Faculty of Sports Sciences, Universidad Europea de Madrid, Madrid, Spain
- Studies Centre in Applied Combat (CESCA), Toledo, Spain
| | - Juan Mielgo-Ayuso
- Department of Health Sciences, Faculty of Health Sciences, University of Burgos, Burgos, Spain
| | - Domingo Jesús Ramos-Campo
- LFE Research Group, Department of Health and Human Performance, Faculty of Physical Activity and Sport Science-INEF, Universidad Politécnica de Madrid, Madrid, Spain
| | | | - Ismael Martínez-Guardado
- BRABE Group, Department of Psychology, Faculty of Life and Natural Sciences, Universidad Camilo José Cela, Madrid, Spain
| | | | - Laura Redondo-Flórez
- Department of Health Sciences, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, Madrid, Spain
| | | | - Jose Francisco Tornero-Aguilera
- Faculty of Sports Sciences, Universidad Europea de Madrid, Madrid, Spain
- Studies Centre in Applied Combat (CESCA), Toledo, Spain
| |
Collapse
|
2
|
Johnston JD, Cowger AE, Weber KS. Bioaerosol and microbial exposures from residential evaporative coolers and their potential health outcomes: A review. INDOOR AIR 2022; 32:e13082. [PMID: 36168234 PMCID: PMC9826010 DOI: 10.1111/ina.13082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/10/2022] [Accepted: 07/08/2022] [Indexed: 06/16/2023]
Abstract
Evaporative cooling is an energy efficient form of air conditioning in dry climates that functions by pulling hot, dry outdoor air across a wet evaporative pad. While evaporative coolers can help save energy, they also have the potential to influence human health. Studies have shown residential evaporative coolers may pull outdoor air pollutants into the home or contribute to elevated levels of indoor bioaerosols that may be harmful to health. There is also evidence that evaporative coolers can enable a diverse microbial environment that may confer early-life immunological protection against the development of allergies and asthma or exacerbate these same hypersensitivities. This review summarizes the current knowledge of bioaerosol and microbiological studies associated with evaporative coolers, focusing on harmful and potentially helpful outcomes from their use. We evaluate the effects of evaporative coolers on indoor bacterial endotoxins, fungal β-(1 → 3)-D-glucans, dust mite antigens, residential microbial communities, and Legionella pneumophila. To our knowledge, this is the first review to summarize and evaluate studies on the influence that evaporative coolers have on the bioaerosol and microbiological profile of homes. This brings to light a gap in the literature on evaporative coolers, which is the lack of data on health effects associated with their use.
Collapse
Affiliation(s)
| | | | - K. Scott Weber
- Department of Microbiology & Molecular BiologyBrigham Young UniversityProvoUtahUSA
| |
Collapse
|
3
|
Riederer AM, Krenz JE, Tchong-French MI, Torres E, Perez A, Younglove LR, Jansen KL, Hardie DC, Farquhar SA, Sampson PD, Metwali N, Thorne PS, Karr CJ. Effectiveness of portable HEPA air cleaners on reducing indoor endotoxin, PM 10, and coarse particulate matter in an agricultural cohort of children with asthma: A randomized intervention trial. INDOOR AIR 2021; 31:1926-1939. [PMID: 34288127 PMCID: PMC8577577 DOI: 10.1111/ina.12858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 04/05/2021] [Accepted: 05/02/2021] [Indexed: 06/13/2023]
Abstract
We conducted a randomized trial of portable HEPA air cleaners in the homes of children age 6-12 years with asthma in the Yakima Valley, Washington. All families received asthma education while intervention families also received two HEPA cleaners (child's bedroom, living room). We collected 14-day integrated samples of endotoxin in settled dust and PM10 and PM10-2.5 in the air of the children's bedrooms at baseline and one-year follow-up, and used linear regression to compare follow-up levels, adjusting for baseline. Seventy-one families (36 HEPA, 35 control) completed the study. Baseline geometric mean (GSD) endotoxin loadings were 1565 (6.3) EU/m2 and 2110 (4.9) EU/m2 , respectively, in HEPA vs. control homes while PM10 and PM10-2.5 were 22.5 (1.9) μg/m3 and 9.5 (2.9) μg/m3 , respectively, in HEPA homes, and 19.8 (1.8) μg/m3 and 7.7 (2.0) μg/m3 , respectively, in control homes. At follow-up, HEPA families had 46% lower (95% CI, 31%-57%) PM10 on average than control families, consistent with prior studies. In the best-fit heterogeneous slopes model, HEPA families had 49% (95% CI, 6%-110%) and 89% lower (95% CI, 28%-177%) PM10-2.5 at follow-up, respectively, at 50th and 75th percentile baseline concentrations. Endotoxin loadings did not differ significantly at follow-up (4% lower, HEPA homes; 95% CI, -87% to 50%).
Collapse
Affiliation(s)
- Anne M. Riederer
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Jennifer E. Krenz
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Maria I. Tchong-French
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Elizabeth Torres
- Northwest Communities Education Center, Radio KDNA, Granger, WA, USA
| | - Adriana Perez
- Yakima Valley Farm Workers Clinic, Toppenish, WA, USA
| | - Lisa R. Younglove
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Karen L. Jansen
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - David C. Hardie
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Stephanie A. Farquhar
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Paul D. Sampson
- Department of Biostatistics, University of Washington, Seattle, WA, USA
| | - Nervana Metwali
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Peter S. Thorne
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Catherine J. Karr
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| |
Collapse
|
4
|
The intersect of genetics, environment, and microbiota in asthma-perspectives and challenges. J Allergy Clin Immunol 2021; 147:781-793. [PMID: 33678251 DOI: 10.1016/j.jaci.2020.08.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/07/2020] [Accepted: 08/05/2020] [Indexed: 02/07/2023]
Abstract
In asthma, a significant portion of the interaction between genetics and environment occurs through microbiota. The proposed mechanisms behind this interaction are complex and at times contradictory. This review covers recent developments in our understanding of this interaction: the "microbial hypothesis" and the "farm effect"; the role of endotoxin and genetic variation in pattern recognition systems; the interaction with allergen exposure; the additional involvement of host gut and airway microbiota; the role of viral respiratory infections in interaction with the 17q21 and CDHR3 genetic loci; and the importance of in utero and early-life timing of exposures. We propose a unified framework for understanding how all these phenomena interact to drive asthma pathogenesis. Finally, we point out some future challenges for continued research in this field, in particular the need for multiomic integration, as well as the potential utility of asthma endotyping.
Collapse
|
5
|
Gehring U, Wijga AH, Koppelman GH, Vonk JM, Smit HA, Brunekreef B. House dust endotoxin, asthma and allergic sensitization through childhood into adolescence. Clin Exp Allergy 2020; 50:1055-1064. [PMID: 32640057 PMCID: PMC7540017 DOI: 10.1111/cea.13705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/28/2020] [Accepted: 07/02/2020] [Indexed: 12/17/2022]
Abstract
Background House dust endotoxin may have beneficial effects on allergic sensitization and asthma in children. Evidence is scarce for adolescents and most studies so far have been cross‐sectional and limited to a single exposure measurement. Objective We assessed associations of house dust endotoxin with asthma and allergic sensitization from birth to age 17 years longitudinally taking into account exposure early in life and at primary school age. Methods We used data of 854 participants of the prospective Dutch PIAMA birth cohort study with house dust endotoxin measurements at 3 months and/or 5‐6 years and data on asthma and/or allergic sensitization from at least one of 11 follow‐ups until age 17. We assessed overall and age‐specific associations of the prevalence of asthma and sensitization with mattress and living room floor dust concentrations (per gram of dust) and loads (per m2 of sampling surface). Results Higher living room floor dust endotoxin concentrations at 3 months were associated with lower odds of asthma until age 4 [odds ratio (95% confidence interval) ranging from 0.70 (0.51‐0.97) at age 1 to 0.76 (0.57‐1.00) at age 3 per interquartile range increase], but not thereafter in children of allergic mothers. Higher living room floor dust endotoxin at 5‐6 years was associated with higher odds of sensitization at 8‐16 years [eg odds ratio (95% confidence interval) 1.70 (1.17‐2.47) per interquartile range increase in endotoxin load]. Conclusions and clinical relevance House dust endotoxin may have beneficial effects on asthma in preschool children of allergic mothers, which do not persist into adolescence. Beneficial associations with allergic sensitization could not be confirmed.
Collapse
Affiliation(s)
- Ulrike Gehring
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Alet H Wijga
- Center for Nutrition, Prevention and Health Services, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Gerard H Koppelman
- Department of Pediatric Pulmonology, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Groningen Research Institute for Asthma and COPD, University of Groningen, Groningen, The Netherlands
| | - Judith M Vonk
- Groningen Research Institute for Asthma and COPD, University of Groningen, Groningen, The Netherlands.,Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Henriëtte A Smit
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
| | - Bert Brunekreef
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.,Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
| |
Collapse
|
6
|
Chu HT, Tran TN, Doyen V, Denis O, Tran TTT, Nguyen TKD, Nguyen HL, Ngo MX, Tran TMH, Corazza F, Bouland C, Hauglustaine JM, Godin I, Michel O. The protective effect of rural life on mite sensitization disappears among urban migrants in the South of Vietnam. World Allergy Organ J 2019; 12:100085. [PMID: 31827665 PMCID: PMC6889047 DOI: 10.1016/j.waojou.2019.100085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/14/2019] [Accepted: 10/03/2019] [Indexed: 12/13/2022] Open
Abstract
Background Rapid urbanization combined with rural migration to urban areas in southern Vietnam could be risk factors for allergen sensitization, contributing to chronic respiratory diseases (CRD). We aimed to evaluate the prevalence of mite sensitization and its relation to house dust characteristics among rural and urban native and migrating populations with CRD. Methods Rural (n = 19) and urban (n = 46) dwellings were defined on the basis of a home typology. Controls were western Belgian houses (n = 14). Besides the house characteristics, both endotoxin and mite allergens were measured in the settled dusts. The sensitization to mite allergens was defined by positive skin prick test (SPT) and concentration of specific IgE (sIgE)≥ 0.7 U/mL. The prevalence of mite sensitization was evaluated among 610 patients with CRD and compared according to both their home types and places of birth and residences. Results The concentration of endotoxin (but not mite allergen) was higher in rural compared to urban dusts (440 (95%CI: 314–566) versus 170 (95%CI: 115–226) EU/mg; p < 0.0001). The prevalence of positive sIgE to Der p1 and Der p2 was significantly lower in rural (9% and 5%) compared to urban (15% and 9%) population, consistent with the positive SPT to mite (14% and 21%, respectively). Among the urban migrants, the risk of mite sensitization (SPT) was higher compared to the rural natives (OR: 1.79 (1.02–3.15), p < 0.05) and not different to the urban ones (OR: 1.35 (0.82–2.23) p NS). Conclusion In Vietnam, associated with higher endotoxin (but not allergen) dust concentrations, the risk of mite sensitization was lower in rural compared to the native urban population, but this protective effect could disappear among rural to urban migrants.
Collapse
Key Words
- APA, Apartment
- Allergens
- Allergy
- CRD, Chronic respiratory diseases
- Dpt, Dermatophagoides pteronyssinus
- EU, Endotoxin unit
- Endotoxin
- Home typology
- PBS, Phosphate buffered saline
- REN, Rent building
- SPT, Skin prick test
- TRA, Traditional home
- TUB, Tube building
- Urban migration
- sIgE, Specific immunoglobulin E
Collapse
Affiliation(s)
- Ha Thi Chu
- Pham Ngoc Thach Hospital, Ho Chi Minh City, Viet Nam.,Clinic of Immuno-allergology, CHU Brugmann, Université Libre de Bruxelles (ULB), 4 Place A Van Gehuchten, B -1020, Brussels, Belgium
| | - Thanh Ngoc Tran
- Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Viet Nam.,School of Public Health, ULB, Brussels, Belgium
| | - Virginie Doyen
- Clinic of Immuno-allergology, CHU Brugmann, Université Libre de Bruxelles (ULB), 4 Place A Van Gehuchten, B -1020, Brussels, Belgium
| | - Olivier Denis
- Service Immune Response, Sciensano, Brussels, Belgium
| | - Thi Thu Thuy Tran
- Industrial University of Ho Chi Minh City, Ho Chi Minh City, Viet Nam
| | | | | | - Minh Xuan Ngo
- Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Viet Nam
| | | | - Francis Corazza
- Laboratory of Immunology, CHU Brugmann, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | | | | | | | - Olivier Michel
- Clinic of Immuno-allergology, CHU Brugmann, Université Libre de Bruxelles (ULB), 4 Place A Van Gehuchten, B -1020, Brussels, Belgium
| |
Collapse
|
7
|
Johnston JD, Cowger AE, Graul RJ, Nash R, Tueller JA, Hendrickson NR, Robinson DR, Beard JD, Weber KS. Associations between evaporative cooling and dust-mite allergens, endotoxins, and β-(1 → 3)-d-glucans in house dust: A study of low-income homes. INDOOR AIR 2019; 29:1005-1017. [PMID: 31463967 DOI: 10.1111/ina.12600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/22/2019] [Accepted: 08/25/2019] [Indexed: 06/10/2023]
Abstract
Recent work suggests that evaporative coolers increase the level and diversity of bioaerosols, but this association remains understudied in low-income homes. We conducted a cross-sectional study of metropolitan, low-income homes in Utah with evaporative coolers (n = 20) and central air conditioners (n = 28). Dust samples (N = 147) were collected from four locations in each home and analyzed for dust-mite allergens Der p1 and Der f1, endotoxins, and β-(1 → 3)-d-glucans. In all sample locations combined, Der p1 or Der f1 was significantly higher in evaporative cooler versus central air conditioning homes (OR = 2.29, 95% CI = 1.05-4.98). Endotoxin concentration was significantly higher in evaporative cooler versus central air conditioning homes in furniture (geometric mean (GM) = 8.05 vs 2.85 EU/mg, P < .01) and all samples combined (GM = 3.60 vs 1.29 EU/mg, P = .03). β-(1 → 3)-d-glucan concentration and surface loads were significantly higher in evaporative cooler versus central air conditioning homes in all four sample locations and all samples combined (P < .01). Our study suggests that low-income, evaporative cooled homes have higher levels of immunologically important bioaerosols than central air-conditioned homes in dry climates, warranting studies on health implications and other exposed populations.
Collapse
Affiliation(s)
- James D Johnston
- Department of Public Health, Brigham Young University, Provo, Utah
| | - Ashlin E Cowger
- Department of Microbiology & Molecular Biology, Brigham Young University, Provo, Utah
| | - Robert J Graul
- Department of Public Health, Brigham Young University, Provo, Utah
| | - Ryan Nash
- Department of Public Health, Brigham Young University, Provo, Utah
| | - Josie A Tueller
- Department of Microbiology & Molecular Biology, Brigham Young University, Provo, Utah
| | | | | | - John D Beard
- Department of Public Health, Brigham Young University, Provo, Utah
| | - K Scott Weber
- Department of Microbiology & Molecular Biology, Brigham Young University, Provo, Utah
| |
Collapse
|
8
|
Fuertes E, Standl M, Markevych I, Bischof W, Heinrich J. Is the association between pet ownership and indoor endotoxin levels confounded or modified by outdoor residential greenspace? THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 625:716-721. [PMID: 29306159 DOI: 10.1016/j.scitotenv.2017.12.333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/11/2017] [Accepted: 12/29/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Pet ownership is consistently associated with higher indoor endotoxin concentrations, but may also be related to the amount of greenspace around the home. This study examined whether the association between pet ownership and higher indoor endotoxin concentrations is confounded or modified by residential greenspace. METHODS Information on pet ownership was collected at the time of recruitment of the German LISA birth cohort. Endotoxin levels were measured in settled house dust sampled from mothers' mattresses (N=1197) and living room floors (N=390). Greenspace around the home was assessed as the mean Normalized Difference Vegetation Index in 100m, 500m and 1000m buffers around the home, and as the distance to the nearest urban and natural green space. Linear regression models assessed cross-sectional associations between pet ownership and log-transformed endotoxin levels, adjusted for known predictors of endotoxin levels. Confounding by greenspace was assessed by additionally adjusting the models for each greenspace variable. Effect modification was assessed by including interaction terms between pet ownership and each greenspace variable, and by model stratification. RESULTS Dog and cat ownership were associated with higher endotoxin levels in mothers' mattresses, whereas only dog ownership was associated with endotoxin levels in the floor samples. All associations were highly robust to further adjustment for greenspace, and there was little evidence to suggest any effect modification (interaction terms had p-values >0.05). CONCLUSIONS Residential greenspace did not confound or modify the association between pet ownership and indoor endotoxin levels. Studies should continue investigating whether pets influence the indoor environment only by their presence, or also by acting as transmission vectors of the outdoors.
Collapse
Affiliation(s)
- Elaine Fuertes
- ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Spain; Universitat Pompeu Fabra (UPF), Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain.
| | - Marie Standl
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Iana Markevych
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany; Institute and Clinic for Occupational, Social and Environmental Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Wolfgang Bischof
- University Hospital Jena, Institute of Occupational, Social and Environmental Medicine, Department of Indoor Climatology, Jena, Germany
| | - Joachim Heinrich
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany; Institute and Clinic for Occupational, Social and Environmental Medicine, University Hospital, LMU Munich, Munich, Germany
| |
Collapse
|
9
|
Lee MK, Carnes MU, Butz N, Azcarate-Peril MA, Richards M, Umbach DM, Thorne PS, Beane Freeman LE, Peddada SD, London SJ. Exposures Related to House Dust Microbiota in a U.S. Farming Population. ENVIRONMENTAL HEALTH PERSPECTIVES 2018; 126:067001. [PMID: 29863827 PMCID: PMC6084882 DOI: 10.1289/ehp3145] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 05/01/2018] [Accepted: 05/02/2018] [Indexed: 05/09/2023]
Abstract
BACKGROUND Environmental factors can influence the house dust microbiota, which may impact health outcomes. Little is known about how farming exposures impact the indoor microbiota. OBJECTIVE We aimed to identify exposures related to bacterial communities in house dust in a U.S. farming population. METHODS We used 16S rRNA amplicon sequencing to characterize bacterial communities in vacuumed dust samples from the bedrooms of a subset of 879 households of farmers and farmers' spouses enrolled in the Agricultural Lung Health Study (ALHS), a case-control study of asthma nested within the Agricultural Health Study (AHS) in North Carolina and Iowa. Information on current farming (past 12 mo), including both crop and animal farming, and other potential microbial sources was obtained via questionnaires. We used linear regression to evaluate associations between exposures and bacterial diversity within each sample, analysis of similarity (ANOSIM), and permutational multivariate analysis of variance (PERMANOVA) to identify exposures related to diversity between samples, and analysis of composition of microbiome to examine whether exposures related to diversity were also related to differential abundance of specific operational taxonomic units (OTUs). RESULTS Current farming was positively associated with bacterial diversity in house dust, with or without adjustment for nonfarm exposures related to diversity, including presence of indoor pets, home condition, and season of dust collection. Many taxa exhibited differential abundance related to farming. Some taxa in the phyla Chloroflexi and Verrucomicrobia were associated [false discovery rate (FDR)<0.05] with farming but not with other nonfarm factors. Many taxa correlated with the concentration of house dust of endotoxin, commonly studied as a general marker of exposure to the farming environment. CONCLUSIONS In this farming population, house dust microbiota differed by current farming status. Understanding the determinants of the indoor microbiota is the first step toward understanding potential relationships with health outcomes. https://doi.org/10.1289/EHP3145.
Collapse
Affiliation(s)
- Mi Kyeong Lee
- Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Megan U Carnes
- Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Natasha Butz
- Dept. of Medicine and Microbiome Core Facility, Center for Gastrointestinal Biology and Disease, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - M Andrea Azcarate-Peril
- Dept. of Medicine and Microbiome Core Facility, Center for Gastrointestinal Biology and Disease, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | | | - David M Umbach
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Peter S Thorne
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, Iowa, USA
| | - Laura E Beane Freeman
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Dept. of Health and Human Services, Rockville, Maryland, USA
| | - Shyamal D Peddada
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Stephanie J London
- Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Dept. of Health and Human Services, Research Triangle Park, North Carolina, USA
| |
Collapse
|
10
|
Lin TH, Su HH, Kang HY, Chang TH. The Interactive Roles of Lipopolysaccharides and dsRNA/Viruses on Respiratory Epithelial Cells and Dendritic Cells in Allergic Respiratory Disorders: The Hygiene Hypothesis. Int J Mol Sci 2017; 18:ijms18102219. [PMID: 29065558 PMCID: PMC5666898 DOI: 10.3390/ijms18102219] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/18/2017] [Accepted: 10/19/2017] [Indexed: 12/15/2022] Open
Abstract
The original hygiene hypothesis declares "more infections in early childhood protect against later atopy". According to the hygiene hypothesis, the increased incidence of allergic disorders in developed countries is explained by the decrease of infections. Epithelial cells and dendritic cells play key roles in bridging the innate and adaptive immune systems. Among the various pattern-recognition receptor systems of epithelial cells and dendritic cells, including toll-like receptors (TLRs), nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) and others, TLRs are the key systems of immune response regulation. In humans, TLRs consist of TLR1 to TLR10. They regulate cellular responses through engagement with TLR ligands, e.g., lipopolysaccharides (LPS) acts through TLR4 and dsRNA acts through TLR3, but there are certain common components between these two TLR pathways. dsRNA activates epithelial cells and dendritic cells in different directions, resulting in allergy-related Th2-skewing tendency in epithelial cells, and Th1-skewing tendency in dendritic cells. The Th2-skewing effect by stimulation of dsRNA on epithelial cells could be suppressed by the presence of LPS above some threshold. When LPS level decreases, the Th2-skewing effect increases. It may be via these interrelated networks and related factors that LPS modifies the allergic responses and provides a plausible mechanism of the hygiene hypothesis. Several hygiene hypothesis-related phenomena, seemingly conflicting, are also discussed in this review, along with their proposed mechanisms.
Collapse
Affiliation(s)
- Tsang-Hsiung Lin
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Kaohsiung 81362, Taiwan.
| | - Hsing-Hao Su
- Department of Otorhinolaryngology-Head & Neck Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan.
| | - Hong-Yo Kang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Kaohsiung 81362, Taiwan.
- Hormone Research Center and Department of Obstetrics and Gynecology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan.
| | - Tsung-Hsien Chang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan.
- Department of Medical Laboratory Science and Biotechnology, Chung Hwa University of Medical Technology, Tainan 71703, Taiwan.
| |
Collapse
|
11
|
Johnston JD, Kruman BA, Nelson MC, Merrill RM, Graul RJ, Hoybjerg TG, Tuttle SC, Myers SJ, Cook RB, Weber KS. Differential effects of air conditioning type on residential endotoxin levels in a semi-arid climate. INDOOR AIR 2017; 27:946-954. [PMID: 28141892 DOI: 10.1111/ina.12369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy-efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan-Apr) and summer (Aug-Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m2 ) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season-by-location comparisons, EU/mg and EU/m2 were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram-negative bacteria or their cell wall components in homes.
Collapse
Affiliation(s)
- J D Johnston
- Department of Health Science, Brigham Young University, Provo, Utah, USA
| | - B A Kruman
- Department of Health Science, Brigham Young University, Provo, Utah, USA
| | - M C Nelson
- Microbiology & Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - R M Merrill
- Department of Health Science, Brigham Young University, Provo, Utah, USA
| | - R J Graul
- Department of Health Science, Brigham Young University, Provo, Utah, USA
| | - T G Hoybjerg
- Microbiology & Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - S C Tuttle
- Department of Health Science, Brigham Young University, Provo, Utah, USA
| | - S J Myers
- Microbiology & Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - R B Cook
- Microbiology & Molecular Biology, Brigham Young University, Provo, Utah, USA
| | - K S Weber
- Microbiology & Molecular Biology, Brigham Young University, Provo, Utah, USA
| |
Collapse
|
12
|
von Mutius E. The microbial environment and its influence on asthma prevention in early life. J Allergy Clin Immunol 2016; 137:680-9. [PMID: 26806048 DOI: 10.1016/j.jaci.2015.12.1301] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/27/2015] [Accepted: 12/05/2015] [Indexed: 12/27/2022]
Abstract
There is accumulating evidence to suggest that the environmental microbiome plays a significant role in asthma development. The very low prevalence of asthma in populations highly exposed to microbial environments (farm children and Amish populations) highlights its preventive potential. This microbial diversity might be necessary to instruct a well-adapted immune response and regulated inflammatory responses to other inhaled and ingested environmental elements, such as allergens, particles, and viruses. Like the internal gut microbiome, which is increasingly recognized as an important instructor of immune maturation, the external environmental microbiome might shape immune responses on the skin, airway mucosal surfaces, and potentially also the gut early in life. The diversity of the external microbial world will ensure that of the many maladapted pathways leading to asthma development, most, if not all, will be counterbalanced. Likewise, important contributors to asthma, such as allergen sensitization and allergic manifestations early in life, are being suppressed. Thus the facets of innate immunity targeted by microbes and their compounds and metabolites might be the master switch to asthma and allergy protection, which has been found in environments rich in microbial exposures.
Collapse
Affiliation(s)
- Erika von Mutius
- Department of Pediatrics, Dr von Hauner Children's Hospital of Ludwig Maximilian University of Munich, Munich, Germany.
| |
Collapse
|
13
|
Holst G, Høst A, Doekes G, Meyer HW, Madsen AM, Sigsgaard T. Determinants of house dust, endotoxin, and β-(1→3)-D-glucan in homes of Danish children. INDOOR AIR 2015; 25:245-59. [PMID: 25039673 DOI: 10.1111/ina.12143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 07/06/2014] [Indexed: 05/24/2023]
Abstract
Little is known about the geographic variation and determinants of bacterial endotoxin and β-(1,3)-D-glucan in Danish house dust. In a population of 317 children, we: (i) described loads and concentrations of floor dust, endotoxin, and β-(1→3)-D-glucan and (ii) their correlations and (iii) assessed their determinants; (iv) Finally, we compared our findings with previous European studies. Bedroom floor dust was analyzed for endotoxin content by the kinetic limulus amoebocyte lysate assay and for β-(1→3)-D-glucan by the inhibition enzyme immunoassay. The parents answered questions regarding potential determinants. We found: geometric means (geometric standard deviations) 186 mg/m(2) (4.3) for dust; 5.46 × 10(3) EU/m(2) (8.0) and 31.1 × 10(3) EU/g (2.6) for endotoxin; and 142 μg/m(2) (14.3) and 0.71 × 10(3) μg/g (7.3) for β-(1→3)-D-glucan. High correlations (r > 0.75) were found between floor dust and endotoxin and β-(1→3)-D-glucan loads, while endotoxin and β-(1→3)-D-glucan concentrations were moderately correlated (r = 0.36-0.41) with the dust load. Having a carpet was positively associated with dust load and with endotoxin and β-(1→3)-D-glucan concentrations. Pet keeping, dwelling type, and dwelling location were determinants of endotoxin concentrations. No other determinants were associated with β-(1→3)-D-glucan concentrations. Compared with other European studies, we found lower β-(1→3)-D-glucan loads and concentrations but higher endotoxin loads and concentrations suggesting a geographically determined different composition of Danish floor dust compared with other European regions.
Collapse
Affiliation(s)
- G Holst
- Section of Environment, Occupation and Health, Aarhus University, Aarhus, Denmark
| | | | | | | | | | | |
Collapse
|
14
|
Patelarou E, Tzanakis N, Kelly FJ. Exposure to indoor pollutants and Wheeze and asthma development during early childhood. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:3993-4017. [PMID: 25872014 PMCID: PMC4410229 DOI: 10.3390/ijerph120403993] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/25/2015] [Accepted: 04/03/2015] [Indexed: 11/16/2022]
Abstract
Background: This review aimed to summarize existing epidemiological evidence of the association between quantitative estimates of indoor air pollution with early childhood respiratory disease. Methods: We carried out a systematic literature search of peer-reviewed epidemiological studies undertaken in “westernized” countries that have assessed exposure to indoor pollutants and asthma and wheeze from infancy up to the age of 5. Results: The search, between January 2004 and February 2014 yielded 1840 studies for consideration. Following application of eligibility criteria to titles and abstracts 22 independent studies were deemed relevant for further review. Two additional studies were next identified through examination of the references’ lists of these studies. Of these 24 selected studies, 16 adopted a prospective cohort design and 8 were case-control studies. Fourteen studies assessed exposure to bio-aerosols, 8 studies assessed exposure to specific air chemicals and two studies assessed exposure to bio-aerosols and air chemicals. Furthermore, 11 studies examined the association of exposure with asthma and 16 with wheeze. Findings indicate that existing studies have reported contradictory effects of indoor pollutants levels and occurrence of asthma/wheeze. Conclusion: Additional research to establish causality and evaluate interventions to prevent disease onset is needed.
Collapse
Affiliation(s)
- Evridiki Patelarou
- Florence Nightingale School of Nursing and Midwifery, King's College London, London SE18WA, UK.
| | - Nikolaos Tzanakis
- Department of Thoracic Medicine, Medical School, University of Crete, Heraklion 71414, Greece.
| | - Frank J Kelly
- MRC-PHE Centre for Environment and Health, NIHR Environmental Hazards Health Protection Research Unit, King's College London, London SE19NH, UK.
| |
Collapse
|
15
|
Jacobs JH, Krop EJM, Borras-Santos A, Zock JP, Taubel M, Hyvarinnen A, Pekkanen J, Doekes G, Heederik DJJ. Endotoxin levels in settled airborne dust in European schools: the HITEA school study. INDOOR AIR 2014; 24:148-157. [PMID: 23927557 DOI: 10.1111/ina.12064] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 08/02/2013] [Indexed: 05/29/2023]
Abstract
Indoor exposure to microbial agents is known to influence respiratory health. Besides home exposure, exposure in schools can affect respiratory health. In this study, we measured endotoxin in settled dust in primary schools in three European countries from three different geographical regions with different climates. Our aim was to characterize endotoxin levels in primary schools and evaluate associations with potential determinants. Endotoxin levels were repeatedly assessed in 23 schools in Spain (n = 7), the Netherlands (n = 10), and Finland (n = 6) using electrostatic dustfall collectors. In total, 645 measurements were taken in 237 classrooms. Endotoxin levels differed significantly between countries; Dutch schools had the highest levels, while Finnish schools showed the lowest levels. In each country, differences in endotoxin levels were observed between schools and over the sampling periods. Estimates improved after adjustment for sampling period. Factors affecting endotoxin levels in a school differed per country. In general, endotoxin levels were higher in lower grades and in classrooms with higher occupancy. School endotoxin levels may contribute significantly to total endotoxin exposure in children and teachers. As the correlation between the repeated measurements is reasonable, single endotoxin measurements form a reasonable basis for estimating annual endotoxin levels in schools.
Collapse
Affiliation(s)
- J H Jacobs
- Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Children's residential exposure to selected allergens and microbial indicators: endotoxins and (1→3)-β-D-glucans. Int J Occup Med Environ Health 2014; 26:870-89. [PMID: 24464566 DOI: 10.2478/s13382-013-0156-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 10/23/2013] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVES The study was aimed at assessment of exposure to endotoxins, (1→3)-β-D-glucans and mite, cockroach, cat, dog allergens present in settled dust in premises of children as agents which may be significantly correlated with the occurrence of allergic symptoms and diseases in children. MATERIALS AND METHODS The study covered 50 homes of one-or two-year-old children in Poland. Samples of settled dust were taken from the floor and the child's bed. The levels of (1→3)-β-D-glucans (floor), endotoxins (floor) and allergens of mite, cat, dog and cockroach (floor and bed) were analyzed. RESULTS Average geometric concentrations (geometric standard deviation) of endotoxins, (1→3)-β-D-glucans, Der p1, Fel d1, Can f1 and Bla g1 in children homes were on the floor 42 166.0 EU/g (3.2), 20 478.4 ng/g (2.38), 93.9 ng/g (6.58), 119.8 ng/g (13.0), 288.9 ng/g (3.4), 0.72 U/g (4.4) and in their beds (only allergens) 597.8 ng/g (14.2), 54.1 ng/g (4.4), 158.6 ng/g (3.1) 0.6 U/g (2.9), respectively. When the floor was covered with the carpet, higher concentrations of endotoxins, (1→3)-β-D-glucans and allergens (each type) were found in the settled dust (p < 0.05). The trend was opposite in case of allergens (except dog) analyzed from bed dust and significantly higher concentrations were found in the rooms with smooth floor (p < 0.05). CONCLUSIONS Among the analyzed factors only the type of floor significantly modified both the level of biological indicators and allergens. The results of this study could be the base for verifying a hypothesis that carpeting may have a protective role against high levels of cockroach, dog and cat allergens.
Collapse
|
17
|
Early life exposures to home dampness, pet ownership and farm animal contact and neuropsychological development in 4 year old children: A prospective birth cohort study. Int J Hyg Environ Health 2013; 216:690-7. [DOI: 10.1016/j.ijheh.2012.12.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 12/21/2012] [Accepted: 12/27/2012] [Indexed: 11/18/2022]
|
18
|
Wan GH, Yan DC, Tung TH, Tang CS, Liu CH. Seasonal Changes in Endotoxin Exposure and Its Relationship to Exhaled Nitric Oxide and Exhaled Breath Condensate pH Levels in Atopic and Healthy Children. PLoS One 2013; 8:e66785. [PMID: 23840530 PMCID: PMC3686731 DOI: 10.1371/journal.pone.0066785] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 05/13/2013] [Indexed: 11/20/2022] Open
Abstract
Endotoxin, a component of the cell walls of gram-negative bacteria, is a contaminant in organic dusts (house dust) and aerosols. In humans, small amounts of endotoxin may cause a local inflammatory response. Exhaled nitric oxide (eNO) levels, an inflammation indicator, are associated with the pH values of exhaled breath condensate (EBC). This study evaluated seasonal changes on indoor endotoxin concentrations in homes and the relationships between endotoxin exposure and eNO/EBC pH levels for healthy children and children with allergy-related respiratory diseases. In total, 34 children with allergy-related respiratory diseases and 24 healthy children were enrolled. Indoor air quality measurements and dust sample analysis for endotoxin were conducted once each season inside 58 surveyed homes. The eNO, EBC pH levels, and pulmonary function of the children were also determined. The highest endotoxin concentrations were on kitchen floors of homes of children with allergy-related respiratory diseases and healthy children, and on bedroom floors of homes of asthmatic children and healthy children. Seasonal changes existed in endotoxin concentrations in dust samples from homes of children with allergic rhinitis, with or without asthma, and in EBC pH values among healthy children and those with allergy-related respiratory diseases. Strong relationships existed between endotoxin exposure and EBC pH values in children with allergic rhinitis.
Collapse
Affiliation(s)
- Gwo-Hwa Wan
- Department of Respiratory Therapy, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- * E-mail:
| | - Dah-Chin Yan
- Division of Taipei Pediatrics, Department of Pediatrics, Chang Gung Children’s Hospital, Chang Gung Memorial Hospital, Taipei, Taiwan
- Department of Medicine, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- Department of Respiratory Therapy, Chang Gung Memorial Hospital, Taipei, Taiwan
| | - Tao-Hsin Tung
- Department of Medical Research and Education, Cheng-Hsin General Hospital, Taipei, Taiwan
| | - Chin-Sheng Tang
- Department of Public Health, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Chiu-Hsin Liu
- Department of Respiratory Therapy, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| |
Collapse
|
19
|
Casas L, Tischer C, Wouters IM, Valkonen M, Gehring U, Doekes G, Torrent M, Pekkanen J, Garcia-Esteban R, Hyvärinen A, Heinrich J, Sunyer J. Endotoxin, extracellular polysaccharides, and β(1-3)-glucan concentrations in dust and their determinants in four European birth cohorts: results from the HITEA project. INDOOR AIR 2013; 23:208-18. [PMID: 23176390 DOI: 10.1111/ina.12017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 11/12/2012] [Indexed: 05/15/2023]
Abstract
UNLABELLED Early-life exposure to microbial agents may play a protective role in asthma and allergies development. Geographical differences in the prevalence of these diseases exist, but the differences in early-life indoor microbial agent levels and their determinants have been hardly studied. We aimed to describe the early-life levels of endotoxin, extracellular polysaccharides (EPS), and β(1-3)-glucans in living room dust of four geographically spread European birth cohorts (LISA in Germany, PIAMA in the Netherlands, INMA in Spain, and LUKAS2 in Finland) and to assess their determinants. A total of 1572 dust samples from living rooms of participants were analyzed for endotoxin, Penicillium/Aspergillus EPS, and β(1-3)-glucans. Information on potential determinants was obtained through questionnaires. Concentrations of endotoxin, EPS, and β(1-3)-glucans were different across cohorts. Concentrations of endotoxin and EPS were respectively lower and higher in INMA than in other cohorts, while glucans were higher in LUKAS2. Season of sampling, dog ownership, dampness, and the number of people living at home were significantly associated with concentrations of at least one microbial agent, with heterogeneity of effect estimates of the determinants across cohorts. In conclusion, both early-life microbial exposure levels and exposure determinants differ across cohorts derived from diverse European countries. PRACTICAL IMPLICATIONS This study adds evidence of variability in the levels of indoor endotoxin, extracellular polysaccharide, and β(1-3)-glucans across four geographically spread European regions. Furthermore, we observed heterogeneity across regions in the effect of exposure determinants. We hypothesize that the variations observed in our study may play a role in the differences in asthma and allergies prevalences across countries.
Collapse
Affiliation(s)
- L Casas
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Ownby DR, Peterson EL, Wegienka G, Woodcroft KJ, Nicholas C, Zoratti E, Johnson CC. Are cats and dogs the major source of endotoxin in homes? INDOOR AIR 2013; 23:219-226. [PMID: 23167871 PMCID: PMC4005287 DOI: 10.1111/ina.12016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 11/13/2012] [Indexed: 05/31/2023]
Abstract
UNLABELLED Previous studies have suggested that exposure to cats and dogs during early childhood reduces the risk of allergic disease, possibly by increasing home endotoxin exposure. This study asked the question of whether cats and dogs are the dominant influence on dust endotoxin concentrations in homes after considering other variables reportedly associated with endotoxin. The presence of cats or dogs in homes, household and home characteristics, and dust endotoxin concentrations from 5 locations were assessed in 966 urban and suburban homes. Whether considered together as pets or as cats and dogs separately, the presence of cats and dogs significantly contributed to living room and bedroom floor endotoxin concentrations, but not to bed endotoxin concentrations. However, the two variables consistently related to endotoxin in all home sites were the home occupant density (occupants/room) and cleanliness of the home. Our data suggest that reducing occupant density and improving home cleanliness would reduce home endotoxin concentrations more than removing pet cats or dogs from the home. PRACTICAL IMPLICATIONS Many studies have shown that early childhood exposure to indoor cats or dogs is associated with a reduced risk of later allergic disease and asthma. An important question is whether alteration in allergic risk associated with cat and dog exposure results from increased endotoxin exposure or from some other associated exposure. Our findings show that cats and dogs are not the dominant source of endotoxin in homes; rather, the density of human occupation and poor cleaning contribute more consistently to higher home endotoxin concentrations especially in the beds.
Collapse
Affiliation(s)
- D R Ownby
- Division of Allergy, Immunology, Rheumatology, Department of Pediatrics, Georgia Health Sciences University, Augusta, GA 30912-3790, USA.
| | | | | | | | | | | | | |
Collapse
|
21
|
Gehring U, Casas M, Brunekreef B, Bergström A, Bonde JP, Botton J, Chévrier C, Cordier S, Heinrich J, Hohmann C, Keil T, Sunyer J, Tischer CG, Toft G, Wickman M, Vrijheid M, Nieuwenhuijsen M. Environmental exposure assessment in European birth cohorts: results from the ENRIECO project. Environ Health 2013; 12:8. [PMID: 23343014 PMCID: PMC3564791 DOI: 10.1186/1476-069x-12-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 01/08/2013] [Indexed: 05/24/2023]
Abstract
Environmental exposures during pregnancy and early life may have adverse health effects. Single birth cohort studies often lack statistical power to tease out such effects reliably. To improve the use of existing data and to facilitate collaboration among these studies, an inventory of the environmental exposure and health data in these studies was made as part of the ENRIECO (Environmental Health Risks in European Birth Cohorts) project. The focus with regard to exposure was on outdoor air pollution, water contamination, allergens and biological organisms, metals, pesticides, smoking and second hand tobacco smoke (SHS), persistent organic pollutants (POPs), noise, radiation, and occupational exposures. The review lists methods and data on environmental exposures in 37 European birth cohort studies. Most data is currently available for smoking and SHS (N=37 cohorts), occupational exposures (N=33), outdoor air pollution, and allergens and microbial agents (N=27). Exposure modeling is increasingly used for long-term air pollution exposure assessment; biomonitoring is used for assessment of exposure to metals, POPs and other chemicals; and environmental monitoring for house dust mite exposure assessment. Collaborative analyses with data from several birth cohorts have already been performed successfully for outdoor air pollution, water contamination, allergens, biological contaminants, molds, POPs and SHS. Key success factors for collaborative analyses are common definitions of main exposure and health variables. Our review emphasizes that such common definitions need ideally be arrived at in the study design phase. However, careful comparison of methods used in existing studies also offers excellent opportunities for collaborative analyses. Investigators can use this review to evaluate the potential for future collaborative analyses with respect to data availability and methods used in the different cohorts and to identify potential partners for a specific research question.
Collapse
Affiliation(s)
- Ulrike Gehring
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Maribel Casas
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Pamplona, Spain
| | - Bert Brunekreef
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Anna Bergström
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Jens Peter Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg University Hospital, Copenhagen NV, Denmark
| | - Jérémie Botton
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Pamplona, Spain
| | - Cecile Chévrier
- INSERM U1085 - IRSET, University of Rennes I, Rennes, France
| | | | - Joachim Heinrich
- Helmholtz Zentrum, München & German Research Centre for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany
| | - Cynthia Hohmann
- Institute of Social Medicine, Epidemiology and Health Economics, Charité University Medical Center Berlin, Berlin, Germany
| | - Thomas Keil
- Institute of Social Medicine, Epidemiology and Health Economics, Charité University Medical Center Berlin, Berlin, Germany
| | - Jordi Sunyer
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Pamplona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Christina G Tischer
- Helmholtz Zentrum, München & German Research Centre for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany
| | - Gunnar Toft
- Department of Occupational Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Magnus Wickman
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Martine Vrijheid
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Pamplona, Spain
| | - Mark Nieuwenhuijsen
- Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Pamplona, Spain
| |
Collapse
|
22
|
Sheehan WJ, Hoffman EB, Fu C, Baxi SN, Bailey A, King EM, Chapman MD, Lane JP, Gaffin JM, Permaul P, Gold DR, Phipatanakul W. Endotoxin exposure in inner-city schools and homes of children with asthma. Ann Allergy Asthma Immunol 2012; 108:418-22. [PMID: 22626594 DOI: 10.1016/j.anai.2012.04.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 03/30/2012] [Accepted: 04/02/2012] [Indexed: 11/26/2022]
Abstract
BACKGROUND Endotoxins are stimulators of the immune system and, despite their potential to protect against allergy, have been associated with early wheezing and asthma morbidity. OBJECTIVE To compare inner-city school endotoxin exposure with home endotoxin exposure in children with asthma. METHODS Students with asthma were recruited from 12 urban elementary schools. Settled and airborne dust samples, linked to enrolled students, were collected from school classrooms, gymnasiums, and cafeterias twice during the academic year. For comparison, settled dust was collected once from the bedrooms of students with asthma. RESULTS Two hundred twenty-nine school settled dust samples and 118 bedroom settled dust samples were collected and analyzed for endotoxin. The median endotoxin concentration for school samples was 13.4 EU/mg (range, 0.7-360.7 EU/mg) and for home samples was 7.0 EU/mg (range = LLOD-843.0 EU/mg). The median concentration within each individual school varied from 6.6 EU/mg to 24.0 EU/mg. One hundred four students with asthma had matched classroom and bedroom endotoxin exposure measurements performed in the same season and demonstrated significantly higher concentrations of endotoxin in the students' classrooms (mean log value, 1.13 vs 0.99, P = .04). The median of the classrooms was 12.5 EU/mg compared with their bedrooms, with a median of 7.0 EU/mg. Within the school environment, no significant difference was seen between the fall and spring samples (mean log value 1.14 vs 1.09; P = .35). CONCLUSION Inner-city children with asthma were exposed to higher concentrations of endotoxin in their classrooms as compared with their bedrooms. Further studies are needed to evaluate school endotoxin exposure as a factor in asthma morbidity.
Collapse
Affiliation(s)
- William J Sheehan
- Department of Pediatrics, Division of Allergy and Immunology, Children's Hospital, 300 Longwood Ave., Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Heederik D, von Mutius E. Does diversity of environmental microbial exposure matter for the occurrence of allergy and asthma? J Allergy Clin Immunol 2012; 130:44-50. [PMID: 22502794 DOI: 10.1016/j.jaci.2012.01.067] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 01/19/2012] [Accepted: 01/23/2012] [Indexed: 10/28/2022]
Abstract
This review describes the recent literature on microbial exposures and protective effects for asthma and atopy. Certain microorganism-associated molecular patterns have been identified as agents that might influence the development of the immune system, which in turn leads to protective effects for asthma and atopy. Endotoxins from gram-negative bacteria were the first agents associated with a reduced risk for asthma and atopy. In later studies, β(1→3)glucans, extracellular polysaccharides, and muramic acid from, respectively, molds and gram-positive bacteria were associated with a reduced risk of allergy and asthma separately in rural and urban populations. These results already suggested that not just one but several independent microbial signals from gram-negative and gram-positive bacteria, as well as molds, might play a role in explaining the protective effects. Recently, the diversity of microbial exposure has been associated with such a reduced risk in farmers' children. Surprisingly, the diversity of both fungal and bacterial exposure seemed to have protective effects. These results open new areas of research and create complex challenges. Methodological issues, such as environmental exposure characterization and assessment and elucidation of potential underlying mechanisms, are discussed because these aspects have a major influence on how microbial diversity can be studied in future studies in relation to protective effects for asthma and atopy.
Collapse
Affiliation(s)
- Dick Heederik
- IRAS, Division of Environmental Epidemiology, Utrecht University, Utrecht, The Netherlands.
| | | |
Collapse
|
24
|
Casas L, Tiesler C, Thiering E, Brüske I, Koletzko S, Bauer CP, Wichmann HE, von Berg A, Berdel D, Krämer U, Schaaf B, Lehmann I, Herbarth O, Sunyer J, Heinrich J. Indoor factors and behavioural problems in children: the GINIplus and LISAplus birth cohort studies. Int J Hyg Environ Health 2012; 216:146-54. [PMID: 22487276 DOI: 10.1016/j.ijheh.2012.03.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 03/02/2012] [Accepted: 03/08/2012] [Indexed: 01/04/2023]
Abstract
Indoor microbial agents exposure is associated to depressive symptoms in adults and persistent exposure to indoor mould is associated to poorer cognitive function in children. In our study, we aimed to assess the effects of the exposure to indoor factors associated with increased microbial exposure (mould, dampness and pets) on behavioural problems in children aged 10 years, participating in two German birth cohorts. A total of 4860 children were followed until the age of 10 years, and the strengths and difficulties questionnaire (SDQ) was administered to the parents. Indoor factors were assessed through parental reported questionnaires in periodical surveys. Logistic and multinomial regressions adjusting for potential confounders were performed. Prevalences of borderline/abnormal total scores in the SDQ at 10 years of age were higher in children exposed to mould (aOR=1.23, 95%CI=1.00-1.56), dampness (aOR=1.51, 95%CI=1.10-2.07), and pets (aOR=1.48, 95%CI=1.20-1.94). The dimension "emotional symptoms" showed statistically significant risk estimates for mould and pets, meanwhile "conduct problems" and "hyperactivity/inattention" dimensions only did for pets. No significant associations were found for the "peer relationship problems" dimension. We found a significant strong interaction between dampness and pet, the risk of borderline/abnormal scores in the "total difficulties" scale and the "emotional symptoms" dimension for pets' was at least twice the risk in children with reported dampness than in children without. Our findings point to a potential effect of microbial exposure on children's behavioural problems, especially on emotional disorders, probably mediated through neurotoxicity and immune system activation.
Collapse
Affiliation(s)
- Lidia Casas
- Centre for Research in Environmental Epidemiology, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Chen CM, Thiering E, Doekes G, Zock JP, Bakolis I, Norbäck D, Sunyer J, Villani S, Verlato G, Täubel M, Jarvis D, Heinrich J. Geographical variation and the determinants of domestic endotoxin levels in mattress dust in Europe. INDOOR AIR 2012; 22:24-32. [PMID: 21906176 DOI: 10.1111/j.1600-0668.2011.00740.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
UNLABELLED Endotoxin exposures have manifold effects on human health. The geographical variation and determinants of domestic endotoxin levels in Europe have not yet been extensively described. To investigate the geographical variation and determinants of domestic endotoxin concentrations in mattress dust in Europe using data collected in the European Community Respiratory Health Survey follow-up (ECRHS II). Endotoxin levels were measured in mattress dust from 974 ECRHS II participants from 22 study centers using an immunoassay. Information on demographic, lifestyle, and housing characteristics of the participants was obtained in face-to-face interviews. The median endotoxin concentration in mattress dust ranged from 772 endotoxin units per gram (EU/g) dust in Reykjavik, Iceland, to 4806 EU/g in Turin, Italy. High average outdoor summer temperature of study center, cat or dog keeping, a high household crowding index, and visible damp patches in the bedroom were significantly associated with a higher endotoxin concentrations in mattress dust. There is a large variability in domestic endotoxin levels across Europe. Average outdoor summer temperature of study center, which explains only 10% of the variation in domestic endotoxin level by center, is the strongest meteorological determinant. The observed variation needs to be taken into account when evaluating the health effects of endotoxin exposures in international contexts. PRACTICAL IMPLICATIONS The incoherent observations of the health effects of endotoxin may be partly owing to the geographical heterogeneity of endotoxin exposure. Therefore, the observed variation should be considered in further studies. Measurements of indoor endotoxin are recommended as an indicator for the level of exposures of individual domestic environments.
Collapse
Affiliation(s)
- C-M Chen
- Helmholtz Zentrum München, German Research Centre for Environmental Health, Institute of Epidemiology, Neuherberg, Germany.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Doyen V, Johansson AB, Hanssens L, Dehennin N, Dinh DHP, Casimir G, Michel O. Relationship between the presence of newborn and the house dust endotoxin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:5313-5317. [PMID: 21975002 DOI: 10.1016/j.scitotenv.2011.09.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 09/07/2011] [Accepted: 09/08/2011] [Indexed: 05/31/2023]
Abstract
BACKGROUND Exposure to house dust endotoxin induces of airways' inflammation. Endotoxin are produced by the Gram-negative bacteria, which are released into the stools and could contaminate domestic environment. OBJECTIVE The newborn could contaminate his mattress by endotoxin. METHODS The dusts of mattress and carpets of 97 newborn' dwellings were sampled at birth and after six months of life. Samplings were made in the bedroom from the baby and in the second place where the baby spent the longer time. The endotoxin concentration was measured by a quantitative Limulus assay and the bacterial contamination was evaluated using 3 selective agar media. RESULTS Endotoxin concentration at birth was positively associated with the presence of both sibling and the number of inhabitants (p<0.01). At 6 months of life, the endotoxin concentration raised significantly not only in the mattresses (from a median of 17.6 (ranges: 0.4-346.7) to 79.6 (3.8-518.8) EU/mg) (p<0.0001), but also in the dust from the second place where the baby is sleeping (from 20.4 (0.8-226.3) to 101.8 (6.5-634.3) EU/mg) (p<0.001). Importantly, there was no change in endotoxin concentration from the carpets dust, and the environmental dwelling characteristics remained unchanged. The total bacterial contamination was also positively associated with endotoxin concentration in newborn mattress at birth (p<0.01) and showed a significant increase at 6 months of life of the newborn (p<0.01). CONCLUSION The newborn is a significant source of house dust's endotoxin.
Collapse
Affiliation(s)
- Virginie Doyen
- Clinic of Immuno-allergology, CHU Brugmann, Université Libre de Bruxelles (ULB), and Neonatal Intensive Care Unit, Hôpital Universitaire Des Enfants Reine Fabiola, HUDERF, ULB, Brussels, Belgium
| | | | | | | | | | | | | |
Collapse
|
27
|
Singh U, Levin L, Grinshpun SA, Schaffer C, Adhikari A, Reponen T. Influence of home characteristics on airborne and dustborne endotoxin and β-D-glucan. ACTA ACUST UNITED AC 2011; 13:3246-53. [PMID: 22012201 DOI: 10.1039/c1em10446b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aim of this study was to assess the associations between airborne and dustborne microbial contaminants (endotoxin and β-D-glucan) and estimate the effects of home characteristics on exposure levels of these microbial contaminants. Endotoxin and β-D-glucan concentrations in airborne inhalable particles, airborne PM1 (<1 μm) and vacuumed dust from 184 residential homes were determined using specific Limulus amebocyte assays. Home characteristics were recorded by visual inspection and questionnaires. Linear regression and correlation analyses were performed. Inhalable endotoxin correlated with dust endotoxin (r = 0.34, p < 0.001) and PM1 endotoxin (r = 0.33, p < 0.001). Inhalable β-D-glucan correlated with dust β-D-glucan (r = 0.18, p < 0.01), but not with PM1 β-D-glucan. Significant correlation was also found between PM1 and dust concentrations for endotoxin (r = 0.26, p < 0.001), but not for β-D-glucan. Multivariate regression analyses showed only one significant association between airborne contaminants and environmental characteristics: inhalable β-D-glucan was positively associated with relative humidity with an effect size (change in the dependent variable corresponding to a unit increase in the independent variable) of 2.32 and p < 0.05. In contrast, several associations were found between dust concentrations and environmental characteristics. Dust endotoxin was positively associated with temperature (2.87, p < 0.01) and number of inhabitants (2.76, p < 0.01), whereas dust β-D-glucan was inversely associated with the presence of dogs (-2.24, p < 0.05) and carpet (-3.05, p < 0.01) in the home. In conclusion, dustborne contaminants were more strongly affected by home characteristics than airborne contaminants. Furthermore, even though statistically significant, the correlations between airborne and dustborne contaminants were weak. This indicates that airborne concentrations cannot be reliably predicted based on dustborne concentrations.
Collapse
Affiliation(s)
- Umesh Singh
- Department of Environmental Health, University of Cincinnati, P.O. Box 670056, Cincinnati, OH 45267-0056, USA
| | | | | | | | | | | |
Collapse
|
28
|
Moniruzzaman S, Hägerhed Engman L, James P, Sigsgaard T, Thorne PS, Sundell J, Bornehag CG. Levels of endotoxin in 390 Swedish homes: determinants and the risk for respiratory symptoms in children. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2011; 22:22-36. [PMID: 21707246 DOI: 10.1080/09603123.2011.588322] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Endotoxins are microbiological agents which ubiquitously exist in an indoor environment, and are believed to be causal agents for a number of diseases. This study investigated the indoor levels and determinants of endotoxins and their impact on asthma and allergy diseases among Swedish pre-school children. House dust samples from 390 homes of 198 case children with asthma and allergy and 202 healthy control children were collected in the Dampness Building and Health (DBH) study. House dust endotoxin levels in the child's bedroom and living rooms ranged from 479-188,000 EU/g dust and from 138-942,000 EU/g dust, respectively. Pet-keeping and agricultural activities were significantly associated with the higher endotoxin concentration levels in indoor dust. Endotoxins in theindoor environment did not associate to asthma and allergy diseases in the children. However, we found an association between endotoxins and the presence of disease symptoms in the sub-group of families without indoor pets.
Collapse
|
29
|
Caillaud D, Evrard B, Laurichesse H, Souweine B. Rôle des endotoxines de l’environnement intérieur dans les symptômes asthmatiques. ARCH MAL PROF ENVIRO 2011. [DOI: 10.1016/j.admp.2010.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
30
|
Sordillo JE, Alwis UK, Hoffman E, Gold DR, Milton DK. Home characteristics as predictors of bacterial and fungal microbial biomarkers in house dust. ENVIRONMENTAL HEALTH PERSPECTIVES 2011; 119:189-95. [PMID: 20965804 PMCID: PMC3040605 DOI: 10.1289/ehp.1002004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Accepted: 10/21/2010] [Indexed: 05/03/2023]
Abstract
BACKGROUND Measurement of fungal and bacterial biomarkers can be costly, but it is not clear whether home characteristics can be used as a proxy of these markers, particularly if the purpose is to differentiate specific classes of biologic exposures that have similar sources but may have different effects on allergic disease risk. OBJECTIVE We evaluated home characteristics as predictors of multiple microbial biomarkers, with a focus on common and unique determinants and with attention to the extent of their explanatory ability. METHODS In 376 Boston-area homes enrolled in a cohort study of home exposures and childhood asthma, we assessed the relationship between home characteristics gathered by questionnaire and measured gram-negative bacteria (GNB) (endotoxin and C10:0, C12:0, and C14:0 3-hydroxy fatty acids), gram-positive bacteria (GPB) (N-acetyl muramic acid), and fungal biomarkers [ergosterol and (1→6) branched, (1→3) β-D glucans] in bed and family room dust. RESULTS Home characteristics related to dampness were significant predictors of all microbial exposures; water damage or visible mold/mildew in the home was associated with a 20-66% increase in GNB levels. Report of cleaning the bedroom at least once a week was associated with reduced GNB, GPB, and fungi. Presence of dogs or cats predicted increases in home bacteria or fungi. The proportion of variance in microbial biomarkers explained by home characteristics ranged from 4.2% to 19.0%. CONCLUSIONS Despite their associations with multiple microbial flora, home characteristics only partially explain the variability in microbial biomarker levels and cannot substitute for specific microbial measurements in studies concerned with distinguishing effects of specific classes of microbes.
Collapse
Affiliation(s)
- Joanne E Sordillo
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
| | | | | | | | | |
Collapse
|
31
|
Samadi S, Rietbroek NNJ, Dwars RM, Jamshidifard AR, Heederik DJJ, Wouters IM. Endotoxin and β-(1 → 3)-glucan exposure in poultry and ruminant clinics. ACTA ACUST UNITED AC 2011; 13:3254-61. [DOI: 10.1039/c1em10566c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
32
|
Heinrich J. Influence of indoor factors in dwellings on the development of childhood asthma. Int J Hyg Environ Health 2010; 214:1-25. [PMID: 20851050 DOI: 10.1016/j.ijheh.2010.08.009] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 08/18/2010] [Accepted: 08/18/2010] [Indexed: 01/21/2023]
Abstract
Asthma has become the most common, childhood chronic disease in the industrialized world, and it is also increasing in developing regions. There are huge differences in the prevalence of childhood asthma across countries and continents, and there is no doubt that the prevalence of asthma was strongly increasing during the past decades worldwide. Asthma, as a complex disease, has a broad spectrum of potential determinants ranging from genetics to life style and environmental factors. Environmental factors are likely to be important in explaining the regional differences and the overall increasing trend towards asthma's prevalence. Among the environmental conditions, indoor factors are of particular interest because people spend more than 80% of their time indoors globally. Increasing prices for oil, gas and other sources of primary energy will further lead to better insulation of homes, and ultimately to reduced energy costs. This will decrease air exchange rates and will lower the dilution of indoor air mass with ambient air. Indoor air quality and potential health effects will therefore be an area for future research and for gaining a better understanding of asthma epidemics. This strategic review will summarize the current knowledge of the effects of a broad spectrum of indoor factors on the development of asthma in childhood in Western countries based on epidemiological studies. In conclusion, several epidemiological studies point out, that indoor factors might cause asthma in childhood. Stronger and more consistent findings are seen when exposure to these indoor factors is assessed by surrogates for the source of the actual toxicants. Measurement-based exposure assessments for several indoor factors are less common than using surrogates of the exposure. These studies, however, mainly showed heterogeneous results. The most consistent finding for an induction of asthma in childhood is related to exposure to environmental tobacco smoke, to living in homes close to busy roads, and in damp homes where are visible moulds at home. The causing agents of the increased risk of living in damp homes remained uncertain and needs clarification. Exposure to pet-derived allergens and house dust mites are very commonly investigated and thought to be related to asthma onset. The epidemiological evidence is not sufficient to recommend avoidance measures against pet and dust mites as preventive activities against allergies. More research is also needed to clarify the potential risk for exposure to volatile and semi-volatile organic compounds due to renovation activities, phthalates and chlorine chemicals due to cleaning.
Collapse
Affiliation(s)
- Joachim Heinrich
- Helmholtz Zentrum München, National Research Center for Environmental Health, Institute of Epidemiology, Munich, Germany.
| |
Collapse
|
33
|
Loo CJ, Foty RG, Wheeler AJ, Miller JD, Evans G, Stieb DM, Dell SD. Do questions reflecting indoor air pollutant exposure from a questionnaire predict direct measure of exposure in owner-occupied houses? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2010; 7:3270-97. [PMID: 20948960 PMCID: PMC2954581 DOI: 10.3390/ijerph7083270] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 08/14/2010] [Accepted: 08/18/2010] [Indexed: 11/16/2022]
Abstract
Home characteristic questions are used in epidemiological studies and clinical settings to assess potentially harmful exposures in the home. The objective of this study was to determine whether questionnaire-reported home characteristics can predict directly measured pollutants. Sixty home inspections were conducted on a subsample of the 2006 population-based Toronto Child Health Evaluation Questionnaire. Indoor/outdoor air and settled dust samples were analyzed. Mean Fel d 1 was higher (p < 0.0001) in homes with a cat (450.58 μg/g) versus without (22.28 μg/g). Mean indoor NO(2) was higher (p = 0.003) in homes with gas stoves (14.98 ppb) versus without (8.31 ppb). Self-reported musty odours predicted higher glucan levels (10554.37 μg/g versus 6308.58 μg/g, p = 0.0077). Der f 1 was predicted by the home's age, but not by reports of carpets, and was higher in homes with mean relative humidity > 50% (61.30 μg/g, versus 6.24 μg/g, p = 0.002). Self-reported presence of a cat, a gas stove, musty odours, mice, and the home's age and indoor relative humidity over 50% predicted measured indoor levels of cat allergens, NO(2), fungal glucan, mouse allergens and dust mite allergens, respectively. These results are helpful for understanding the significance of indoor exposures ascertained by self-reporting in large epidemiological studies and also in the clinical setting.
Collapse
Affiliation(s)
- C.K. Jennifer Loo
- University of Toronto, 1 King’s College Circle, Toronto, Ontario M5S 1A8, Canada; E-Mail: (C.K.J.L.)
| | - Richard G. Foty
- The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada; E-Mail: (R.G.F.)
| | - Amanda J. Wheeler
- Health Canada, 269 Laurier Ave West, Ottawa, Ontario K1A 0K9, Canada; E-Mails: (A.J.W.); (D.M.S.)
| | - J. David Miller
- Chemistry Department, Carleton University, Ottawa, Ontario K1S 5B6, Canada; E-Mail: (J.D.M.)
| | - Greg Evans
- University of Toronto, 200 College Street, Toronto, Ontario M5S 2E5, Canada; E-Mail: (G.E.)
| | - David M. Stieb
- Health Canada, 269 Laurier Ave West, Ottawa, Ontario K1A 0K9, Canada; E-Mails: (A.J.W.); (D.M.S.)
| | - Sharon D. Dell
- The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada; E-Mail: (R.G.F.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-416-813-6248; Fax: +1-416-813-6246
| |
Collapse
|
34
|
Caillaud D, Evrard B, Laurichesse H, Souweine B. [Role of indoor endotoxins in asthma symptoms]. Rev Mal Respir 2010; 26:893-9. [PMID: 19953033 DOI: 10.1016/s0761-8425(09)73684-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Endotoxin is a collective term designating a characteristic group of chemical constituents of the outer membrane of Gram negative bacteria, the lipopolysaccharides (LPS). BACKGROUND LPS provocation tests in healthy subjects (50 microg) induce asthma-like airflow obstruction with a neutrophilic inflammatory influx, similar to reactions observed in non-atopic asthma. Asthmatic subjects show the same reaction with smaller doses of LPS (20 microg), revealing higher sensitivity to LPS than normal subjects. Low levels (2 microg) of LPS do not induce either airflow obstruction or bronchial hyperreactivity. Among exposed workers, particularly in agriculture, endotoxin is the most significant component of the bioaerosol that is associated with airway disease. In clinical studies, exposure to LPS is associated with severe asthma. Conversely, epidemiological studies, in both urban and rural areas, assessing the relationship between exposure to LPS and asthma and asthma- related symptoms are inconsistent. PERSPECTIVES Longitudinal epidemiological studies, especially in farm children, may confirm the putative protective effects of LPS with respect to atopic asthma. CONCLUSION Exposure to indoor LPS is frequently associated with asthma and asthma-like symptoms in current studies. Their definitive role needs to be confirmed by birth cohort studies currently under way that should define the controversial protective effect of LPS with respect to atopic asthma in farming populations.
Collapse
Affiliation(s)
- D Caillaud
- Service de Pneumologie, CHU de Clermont-Ferrand, Hôpital Gabriel Montpied, Clermont-Ferrand, France.
| | | | | | | |
Collapse
|
35
|
Simpson A, Martinez FD. The role of lipopolysaccharide in the development of atopy in humans. Clin Exp Allergy 2009; 40:209-23. [PMID: 19968655 DOI: 10.1111/j.1365-2222.2009.03391.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Atopy is a highly prevalent condition and remains the single biggest risk factor for asthma. Although atopy has a heritable component, the time frame of the increase in the prevalence indicates that it is not due to genetic factors alone. The relationship between allergen exposure and sensitization is complex. Lipopolysaccharide (LPS) and its bioactive moiety endotoxin are common to all gram-negative bacteria, and have been used as a surrogate of microbial load. Endotoxin can be readily measured in dust collected from homes. Some studies have demonstrated a clear inverse dose-response relationship between exposure to endotoxin and the risk of atopy but this finding has not been reproduced in all studies. Our innate immune system recognizes LPS readily via the LPS signal transduction pathway, which has the trimolecular complex of CD14/TLR4/MD2 at the core. A common single-nucleotide polymorphism in the promoter region of CD14 rs2569190 C to T (CD14/-260 or CD14/-159) has been associated with elevated sCD14. Although early studies suggested that this variant was associated with more severe atopy, this finding was not uniformly replicated. It has now been demonstrated in four independent populations that high exposure to endotoxin in the domestic environment is protective against the development of atopy, but only among carriers of the C allele, that is, the environmental exposure is only relevant when taken in the context of the genotype. Furthermore, this interaction is biologically plausible. We propose that neither the environmental exposure nor the genotype in isolation is sufficient to cause complex diseases like asthma and atopy, but disease results from the one acting in the context of the other, of which CD14 and endotoxin is one example contributing to the risk for atopy.
Collapse
Affiliation(s)
- A Simpson
- Manchester Academic Health Science Centre, NIHR Translational Research Facility in Respiratory Medicine, University Hospital of South Manchester NHS Foundation Trust, The University of Manchester, Manchester, UK.
| | | |
Collapse
|
36
|
Täubel M, Rintala H, Pitkäranta M, Paulin L, Laitinen S, Pekkanen J, Hyvärinen A, Nevalainen A. The occupant as a source of house dust bacteria. J Allergy Clin Immunol 2009; 124:834-40.e47. [PMID: 19767077 DOI: 10.1016/j.jaci.2009.07.045] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 06/30/2009] [Accepted: 07/27/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Markers for microbial groups are commonly measured in house dust samples to assess indoor exposure to microbes in studies on asthma and allergy. However, little is known about the sources of different microbes. A better understanding of the nature and origin of microbes present in the immediate environment of human beings is crucial if one wants to elucidate protective as well as adverse effects on human health. OBJECTIVE To determine the extent to which the bacterial composition of mattress and floor dust reflects the presence of the human body in relation to other environmental sources. METHODS House dust and skin surface swab samples of occupants in 4 homes were collected and analyzed for their bacterial content, using a culture-independent methodology. Bacterial sequences analyzed from the different house dusts and skin surface swabs represented random samples of bacteria present in a given sample. Highly similar sequences were grouped to assess biodiversity and to draw conclusions about the sources of bacteria. RESULTS The bacterial flora in the house dust samples was found to be highly diverse and dominated by gram-positive bacteria. To a considerable extent, the presence of different bacterial groups was attributed to human sources. In the individuals' mattress dust samples, 69% to 88% of the bacterial sequences analyzed were associated with human origins. The respective percentages for the individual floor dusts ranged from 45% to 55%. CONCLUSION Our study indicates that human-derived bacteria account for a large part of the mainly gram-positive bacterial content in house dust.
Collapse
Affiliation(s)
- Martin Täubel
- Department of Environmental Health, National Institute for Health and Welfare, Kuopio, Finland.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Dassonville C, Demattei C, Vacquier B, Bex-Capelle V, Seta N, Momas I. Indoor airborne endotoxin assessment in homes of Paris newborn babies. INDOOR AIR 2008; 18:480-7. [PMID: 19120498 DOI: 10.1111/j.1600-0668.2008.00549.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The aims of this study were first to assess airborne endotoxin levels in the dwellings of 162 newborns living in Paris twice during a 1-year period, and second, to identify predictors for endotoxin concentrations using questionnaire data in relation to housing factors and living conditions. Air samples were collected on a glass fiber filter in polystyrene filter holders, using a pump at a flow rate of 3.5 l/min for 24 h placed in the main room of the home. Endotoxin levels were measured using a chromogenic kinetic Limulus Amoebocyte Lysate test. Geometric means (geometric standard deviation) of airborne endotoxin levels at two different visits were respectively 0.509 (4.289) EU/m3 and 0.557 (3.029) EU/m3. Airborne endotoxin levels were significantly increased: (i) in cold season (P = 0.024), with (ii) the presence of visible cockroaches in the previous 12 months at home (P < 0.001), (iii) increased number of inhabitants per square meter (P = 0.012), (iv) the high frequency of cleaning with the floor cloths (P = 0.0014), and (v) the low frequency of vacuuming (P = 0.0045). This study provided for the first time airborne endotoxin levels issued from repeated measurements in Paris dwellings. PRACTICAL IMPLICATIONS This analysis contributed to identify a few factors that determined indoor airborne endotoxin levels. However, the predictive model including housing factors and living conditions poorly estimated endotoxin levels. Consequently, multiple samples and longer sampling periods might improve the estimate of long-term airborne endotoxin exposure especially its variability, in cohort studies.
Collapse
Affiliation(s)
- C Dassonville
- Laboratoire Santé Publique et Environnement, Université Paris-Descartes, Paris, France
| | | | | | | | | | | |
Collapse
|
38
|
Aichbhaumik N, Zoratti EM, Strickler R, Wegienka G, Ownby DR, Havstad S, Johnson CC. Prenatal exposure to household pets influences fetal immunoglobulin E production. Clin Exp Allergy 2008; 38:1787-94. [PMID: 18702655 PMCID: PMC3744168 DOI: 10.1111/j.1365-2222.2008.03079.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Early life pet exposure may protect against allergic sensitization during childhood. Few studies have evaluated the effect of prenatal pet exposure on potential neonatal markers of allergic risk. OBJECTIVE The aim of this study was to investigate whether maternal exposure to pets affects cord blood IgE levels in a population-based, general risk, ethnically mixed birth cohort. METHODS Pet keeping during pregnancy was ascertained from women residing in a defined area of Wayne County Michigan and recruited from five staff model obstetric clinics. Maternal venous blood was analysed for total and allergen-specific IgE along with cord blood total IgE from 1049 infants. RESULTS Compared with infants from households with no cats or dogs kept indoors during pregnancy, infants whose homes had either cats or dogs had significantly reduced mean cord IgE levels [0.34 IU/mL (95% CI 0.30-0.38) vs. 0.24 IU/mL (0.20-0.27), P=0.025]. Similar effects were apparent in cat-only households [0.21 IU/mL (0.16-0.27), P=0.020] and dog-only households [0.24 IU/mL (0.19-0.29), P=0.045]. There was no effect on results when excluding mothers who reported avoiding pets due to allergy-related concerns. CONCLUSION Mothers with either cats or dogs in their home during pregnancy deliver children with lower cord blood IgE levels compared with mothers who do not live with these pets, supporting the hypothesis that pet exposure influences immune development in a manner that is protective for atopy and is operant even before birth.
Collapse
Affiliation(s)
| | | | | | - Ganesa Wegienka
- Department of Biostatistics and Research Epidemiology, Henry Ford Hospital
| | | | - Suzanne Havstad
- Department of Biostatistics and Research Epidemiology, Henry Ford Hospital
| | | |
Collapse
|
39
|
Bousquet J, Fokkens W, Burney P, Durham SR, Bachert C, Akdis CA, Canonica GW, Dahlen SE, Zuberbier T, Bieber T, Bonini S, Bousquet PJ, Brozek JL, Cardell LO, Crameri R, Custovic A, Demoly P, van Wijk RG, Gjomarkaj M, Holland C, Howarth P, Humbert M, Johnston SL, Kauffmann F, Kowalski ML, Lambrecht B, Lehmann S, Leynaert B, Lodrup-Carlsen K, Mullol J, Niggemann B, Nizankowska-Mogilnicka E, Papadopoulos N, Passalacqua G, Schünemann HJ, Simon HU, Todo-Bom A, Toskala E, Valenta R, Wickman M, Zock JP. Important research questions in allergy and related diseases: nonallergic rhinitis: a GA2LEN paper. Allergy 2008; 63:842-53. [PMID: 18588549 DOI: 10.1111/j.1398-9995.2008.01715.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nonallergic rhinitis (NAR) can be defined as a chronic nasal inflammation which is not caused by systemic IgE-dependent mechanisms. It is common and probably affects far more than 200 million people worldwide. Both children and adults are affected. However, its exact prevalence is unknown and its phenotypes need to be evaluated using appropriate methods to better understand its pathophysiology, diagnosis and management. It is important to differentiate between infectious rhinitis, allergic/NAR and chronic rhinosinusitis, as management differs for each of these cases. Characterization of the phenotype, mechanisms and management of NAR represents one of the major unmet needs in allergic and nonallergic diseases. Studies on children and adults are required in order to appreciate the prevalence, phenotype, severity and co-morbidities of NAR. These studies should compare allergic and NAR and consider different age group populations including elderly subjects. Mechanistic studies should be carried out to better understand the disease(s) and risk factors and to guide towards an improved diagnosis and therapy. These studies need to take the heterogeneity of NAR into account. It is likely that neuronal mechanisms, T cells, innate immunity and possibly auto-immune responses all play a role in NAR and may also contribute to the symptoms of allergic rhinitis.
Collapse
Affiliation(s)
- J Bousquet
- University Hospital and INSERM, Montpellier, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|