Association between environmental factors and current asthma, rhinoconjunctivitis and eczema symptoms in school-aged children from Oropeza Province - Bolivia: a cross-sectional study

Background: In recent years, the prevalence of asthma,
rhinoconjunctivitis and eczema symptoms in childhood has
considerably increased in developing countries including Bolivia,
possibly due to changes in lifestyle, environmental and domestic
factors. This study aimed to assess the association between
environmental factors and asthma, rhinoconjuctivitis and eczema
symptoms in school-aged children from Oropeza Province in
Chuquisaca, Bolivia. Methods: A cross-sectional study was performed
in 2340 children attending the fifth grade in 36 randomly selected
elementary schools in Oropeza province. The prevalence of symptoms
was determined using the International Study of Asthma and
Allergies in Childhood (ISAAC) questionnaire. Environmental factors
were assessed by the ISAAC environmental questionnaire including
questions related to exposure to pets, farm animals, indoor and
outdoor pollution, presence of disease vectors at home and
precarious household conditions. Generalized linear mixed-effects
models were adjusted for age, sex and place of living. Results:
Thirty seven percent of children reported that at least one of
their parents smoked at home. Wood or coal was used as cooking fuel
in 19\% of the homes and 29\% reported intense truck traffic on the
street where they lived. With respect to hygiene conditions, 86\%
reported exposure to dogs, 59\% exposure to cats and 36\% regular
contact to farm animals. More than one precarious household
condition was reported by 8\% of children. In the adjusted model
exposure to dog (adjusted OR 1.4; CI 95\% 1.0-1.9), cat (1.2;
1.0-1.5), farm animals (1.5; 1.2-1.8); intense truck traffic (1.3;
1.0-1.6), parents smoking at home (1.2; 1.0-1.5), presence of
disease vectors at home (fourth quartile vs. first quartile: 1.6;
1.2-2.3) and two or more precarious household conditions (1.5;
1.0-2.2) were significantly associated with rhinoconjunctivitis
symptoms. The associations were similar for asthma and eczema
symptoms; however it did not reach the level of statistical
significance for all items. Conclusion: Our results support
previous findings reported for poor communities especially in Latin
America, showing that lower hygiene conditions did not have
protective effect against asthma and rhinoconjunctivitis and eczema
symptoms.