RESUMO
BACKGROUND: Children exposed to biomass used in households are at risk to develop diseases or respiratory symptoms. In Madagascar more than 95% of households use it daily. The main objective is to study the impact of chronic exposure to biomass on respiratory health of children under 15 years old in Madagascar. METHODS: Descriptive cross-sectional study conducted with questionnaires among urban and rural population of Antananarivo and Mahajanga provinces between 2016 and 2017. Variables were collected: number of hours spent in kitchen per day, respiratory symptoms and spirometric data. Categorized symptoms score and exposure index expressing chronic exposure to biomass were analyzed with multinomial logistic regression models. RESULTS: Of the 661 children included in the analysis, 27.7% had 1 respiratory symptom and 29.3% had 2 or more respiratory symptoms. Moderate exposure index (aOR=1.57; CI95%=[1.30-1.89]; p<0.001) and high exposure index (aOR=1.76; CI95%=[1.39-2.24]; p<0.001) were significantly associated with 1 respiratory symptom, adjusted with provinces, household members and visitors smoking, perceived discomfort related to air pollution and birthweight. Exposure index was not significantly associated with an increased risk of having 2 or more respiratory symptoms (p = 0.754). CONCLUSION: Respiratory symptoms were associated with exposure to biomass, living in coastal areas, birthweight, tobacco and perceived discomfort related to air pollution. Recommendations and actions must be implemented in order to improve respiratory health related to biomass among children.
Assuntos
Poluição do Ar em Ambientes Fechados , Fumaça , Humanos , Criança , Adolescente , Fumaça/efeitos adversos , Biomassa , Estudos Transversais , Peso ao Nascer , Madagáscar/epidemiologia , Poluição do Ar em Ambientes Fechados/efeitos adversosRESUMO
Epidemiology of asthma. Asthma related death rate was halved in the last 20 years in France. Asthma prevalence was stable or moderately increasing. Asthma control is still incomplete and hospitalization rates are on the increase in asthmatic children. Risk factors include genetic and environmental components. Recently, epigenetic has shed a bridge between both chapters. Pollen allergens behave as a risk factor for seasonal allergic rhinitis occurrence and worsening. The picture is less clear about asthma. In like manner, the relationship between exposure to indoor allergens and asthma occurrence is subject to debate. Thus primary prevention of allergic diseases through allergen avoidance is questionable. By contrast, indoor allergen exposure is indeed an aggravating factor for rhinitis and asthma but secondary prevention is not easy, probably because air contaminants are many and their concentration linked to building characteristics. Indoor chemical land particulate air pollution is a triggering factor for rhinitis and asthmatic symptoms but studies on this topic are still few. By contrast, passive smoking has a well-known deleterious respiratory impact.
Épidémiologie de l'asthme. Le nombre de décès par asthme a diminué de moitié au cours des 20 dernières années. La prévalence de la maladie paraît au contraire stable ou en légère augmentation dans les pays développés dont la France. Mais le niveau de contrôle de la maladie est souvent incomplet, avec des taux d'hospitalisation en hausse chez l'enfant. Les facteurs de risque incluent traditionnellement l'équipement génétique et l'environnement aérien ; l'épigénétique jette aujourd'hui un pont entre les deux. Le rôle des allergènes polliniques dans l'induction et l'aggravation de la rhinite saisonnière est bien documenté. Les conclusions sont moins nettes à propos de l'asthme. Le rôle des allergènes domestiques reste discuté en tant que facteur de risque d'apparition de l'asthme allergique, ce qui questionne l'intérêt de l'éviction allergénique en prévention primaire des maladies allergiques respiratoires. Le rôle aggravant de l'exposition allergénique domestique est, en revanche, bien documenté, mais la prévention secondaire au travers de l'éviction allergénique n'est pas facile car les aérocontaminants impliqués sont multiples et leur concentration liée aux caractéristiques du bâtiment. La pollution chimique de l'habitat constitue un facteur aggravant qui demande à être mieux explicité. Ce n'est pas le cas du tabagisme passif dont les effets délétères sont bien connus.
