Biomass fuel exposure and asthma symptoms among rural school children in Nigeria

ABSTRACT

Background: Approximately 70% of rural Nigerian households rely on biomass fuels for cooking. The International Study of Asthma and Allergies in Childhood (ISAAC) estimates the prevalence of current wheeze among children in Nigeria to have risen from 10.7% in 1999 to approximately 20% in 2014. Objective: To examine the effects of biomass smoke exposure on asthma symptom prevalence in rural children in Nigeria. Methods: We conducted a cross-sectional survey in rural communities in Nigeria. Asthma symptoms were defined according to ISAAC definitions. Biomass smoke exposure was determined by the types of fuel used for cooking. Logistic regression was used to explore associations between biomass smoke and asthma symptoms. Results: The study population comprised 1,690 school children, of which 865 lived in households cooking with biomass and 825 lived in households not using biomass. Asthma symptoms were reported in 481 (28.5%) children. Biomass fuel was associated with increased odds of asthma symptoms. Adjusted odds ratios (aORs) were 1.38 (95% CI: 1.05–1.80) for nocturnal cough, 1.26 (95% CI: 1.00–1.61) for current wheeze, and 1.33 (95% CI: 1.05–1.69) for report of any asthma-related symptoms. Sex modified the associations between asthma symptoms with biomass fuel: aORs were stronger and significant for males (nocturnal cough = 1.85, 95% CI: 1.24–2.76; current wheeze = 1.48, 95% CI: 1.03–2.13; report of any asthma-related symptoms = 1.60, 95% CI: 1.12–2.28), but weaker and non-significant for females.Conclusion: The risk of asthma symptoms related to biomass smoke exposure appears to differ by sex.

KEYWORDS:

• Asthma symptoms
• biomass fuel
• Nigeria
• rural
• school children

Acknowledgments

The authors wish to thank all staff of the HLF for assistance with project execution. We also wish to thank the school principals, parents, and school-children who took time to take part in this study and Monica Palese for editorial assistance.

Declaration of interest

The authors have no conflict of interest related to this study. The authors alone are responsible for the content and writing of this manuscript.

Funding

This study is supported by grant from the Ralph and Marion FALK Medical Trust, Chicago, USA and the Healthy Life for All Foundation (HLF), Ibadan, Nigeria.