Abstract

Background: Increasing evidence show the possible association between chronic obstructive pulmonary disease (COPD) and the use of biomass fuels for cooking and heating in developing countries. Data on COPD prevalence and objective measurement of indoor pollution from biomass fuel has not been widely available from China.

Objectives: To investigate the prevalence of COPD in two study communities in Guangdong province in China and measure the association between COPD and indoor biomass fuel air pollution.

Methods: A cluster-disproportional-random-sampling survey was performed in populations aged over 40 years in urban (Liwang) and rural (Yunyan) areas in Guangdong, China. Spirometry was performed in all subjects and a post-bronchodilator ratio of the forced expiratory volume in the first second over forced vital capacity of less than 0.70 was defined as COPD. Measurements of indoor and outdoor air pollutants were also performed in a random sample of households.

Main Results: The overall prevalence of COPD in the two areas (Liwang and Yunyan) was 9.4%. The prevalence of COPD in both whole population and a subpopulation of non-smoking women in rural Yunyan was significantly higher than that in urban Liwang (12.0% vs 7.4%, and 7.2% vs 2.5% respectively). Biomass fuel use was higher in rural Yunyan than that in urban Liwang (88.1% vs 0.7%). Univariate analysis showed significant association between COPD and exposure to biomass for cooking. Multivariate analysis showed the positive association between COPD and urban/rural area (surrogate for exposure to biomass for cooking and local exhaust ventilation in kitchen) after adjustment for gender, age group, BMI, education, occupational exposure, respiratory disease in family, smoking status, life quality and cough in childhood, and similar results were found in non-smoking women. Pollutants measurements showed that CO, PM10, SO2 and NO2 concentrations in the kitchen during biomass fuel combustion were significantly higher than those during LPG combustion.

Conclusions: Indoor pollutants from biomass fuels may be an important risk factor for COPD in rural South China.