Crowding: risk factor or protective factor for lower respiratory disease in young children?
Open accessAbstract
BACKGROUND: To study the effects of household crowding upon the respiratory health of young children living in the city of São Paulo, Brazil. METHODS: Case-control study with children aged from 2 to 59 months living within the boundaries of the city of São Paulo. Cases were children recruited from 5 public hospitals in central São Paulo with an acute episode of lower respiratory disease. Children were classified into the following diagnostic categories: acute bronchitis, acute bronchiolitis, pneumonia, asthma, post-bronchiolitis wheezing and wheezing of uncertain aetiology. One control, crudely matched to each case with regard to age (<2, 2 years old or more), was selected among healthy children living in the neighborhood of the case. All buildings were surveyed for the presence of environmental contaminants, type of construction and building material. Plans of all homes, including measurements of floor area, height of walls, windows and solar orientation, was performed. Data were analysed using conditional logistic regression. RESULTS: A total of 313 pairs of children were studied. Over 70% of the cases had a primary or an associated diagnosis of a wheezing illness. Compared with controls, cases tended to live in smaller houses with less adequate sewage disposal. Cases and controls were similar with respect to the number of people and the number of children under five living in the household, as well the number of people sharing the child's bedroom. After controlling for potential confounders, no evidence of an association between number of persons sharing the child's bedroom and lower respiratory disease was identified when all cases were compared with their controls. However, when two categories of cases were distinguished (infections, asthma) and each category compared separately with their controls, crowding appeared to be associated with a 60% reduction in the incidence of asthma but with 2 1/2-fold increase in the incidence of lower respiratory tract infections (p = 0.001). CONCLUSION: Our findings suggest that household crowding places young children at risk of acute lower respiratory infection but may protect against asthma. This result is consistent with the hygiene hypothesis.
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Overcrowding raises the risk of lower respiratory infections.
“a risk factor for lower respiratory tract infections.1 , 2”
From Poverty, inequality and COVID-19: the forgotten vulnerable (2020) · cites this paper as [2]
Experimental — accuracy not yet measuredSeven percent of people in the poorest fifth of UK households live in overcrowded housing.
“7% of people from the poorest 20% of UK households live in overcrowded housing”
From Poverty, inequality and COVID-19: the forgotten vulnerable (2020) · cites this paper as [2]
The Background says the study examines household crowding among young children in São Paulo, Brazil; the Results report housing and crowding measures for those study households. Neither section gives a figure for the poorest fifth of UK households. Searches for the UK, the poorest 20%, and 7% found no passage supporting the claimed statistic. (LLM, conf=0.78)
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- Authors
- Cardoso, M. R. A., Cousens, S. N., de Góes Siqueira, L. F., Alves, F. M., & D'Angelo, L. A. V.
- Affiliations
- Universidade de São Paulo (BR)
- University of London (GB)
- Instituto de Saúde (BR)
- Corresponding author
- Cardoso, Maria Regina Alves
- Alves, Fátima Maria
- Venue
- BMC Public Health
- Published
- 2004-06-03
- Volume
- 4
- Issue
- 1
- Pages
- 19-19
- ISSN
- 1471-2458 (ISSN-L)
- PMC
- PMC434510
- OpenAlex
- W1842152428
- Cited by
- 186
- References
- 29
- Citations by year
- 2026: 2 · 2025: 2 · 2024: 6 · 2023: 18 · 2022: 13 · 2021: 16 · 2020: 8 · 2019: 8 · 2018: 8 · 2017: 3 · 2016: 6 · 2015: 12 · 2014: 11 · 2013: 10 · 2012: 8
- FWCI
- 9.55
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- BMC Public Health (publishedVersion)
- PubMed Central (publishedVersion, other-oa)
- PubMed (publishedVersion)
- Portuguese National Funding Agency for Science, Research and Technology (RCAAP Project by FCT) (publishedVersion, other-oa)
- Portuguese National Funding Agency for Science, Research and Technology (RCAAP Project by FCT) (publishedVersion)
- LSHTM Research Online (London School of Hygiene and Tropical Medicine) (acceptedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- Funders
- International Development Research Centre
- Conselho Nacional de Desenvolvimento Científico e Tecnológico
- Topics
- Health Sciences › Health Professions › Emergency Medical Services › Pediatric health and respiratory diseases
- Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Indoor Air Quality and Microbial Exposure
- Health Sciences › Medicine › Physiology › Asthma and respiratory diseases
- Keywords
- household crowding, lower respiratory disease, young children, wheezing, asthma, lower respiratory tract infection, hygiene hypothesis, housing conditions, São Paulo
- MeSH terms
- Acute Disease, Asthma, Brazil, Bronchiolitis, Child, Preschool, Crowding, Family Characteristics, Hospitals, Public, Housing, Humans, Infant, Pneumonia, Residence Characteristics, Respiration Disorders, Respiratory Tract Infections, Risk Factors, Case-Control Studies, Air Pollution, Indoor, Episode of Care
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