Exposure to indoor biomass fuel pollutants and asthma prevalence in Southeastern Kentucky: results from the Burden of Lung Disease (BOLD) study.

Background: Asthma is a chronic inflammatory respiratory disease, characterized by episodic and reversible airflow obstruction and airway hyperresponsiveness and is influenced by both genetic and environmental factors.

Methods: The Burden of Obstructive Lung Disease (BOLD) survey was used to determine the prevalence of self-reported asthma in a target population of 325,000 adults aged > or =40 in Southeastern Kentucky. Postbronchodilator spirometry was used to classify subjects based on lung function. Risk factors for asthma in this population, in particular indoor usage of biomass fuels, were evaluated.

Results: The overall study population was comprised of 508 individuals, with 15.5% reporting current asthma and 5.8% reporting former asthma. In this population, the following risk factors for asthma were identified: female sex, smoking, less than a high school education, increasing body mass index (BMI), and a history of cooking indoors with coal and wood. Cooking indoors with wood and coal for more than 6 months of one's life was shown to significantly increase the odds of reporting current asthma (odds ratio (OR) = 2.3, confidence interval (CI) 1.1, 5.0), whereas no effect was seen from a history of heating indoors with wood and coal (OR = 0.8, CI 0.4, 1.8).

Conclusions: Current or former asthma was reported by 21.3% of the adult population. A history of using biomass fuels when cooking indoors significantly increased the risk of reporting current asthma in this population.