Biomass Pollution, Chimney Stove Interventions, and Discrepant Outcomes

Abstract

In the study by Guarnieri et al1 in this issue of CHEST (see page 1184), the authors reported no evidence for an association between lung function and early randomization to a chimney stove intervention. These findings prompted the authors to conclude that future studies may need to incorporate cleaner stoves or cleaner fuels.1 Personal carbon monoxide (CO) exposures in the chimney woodstoves used in their study were only reduced by 30% following stove installation, while other chimney stoves, such as Patsari (Grupo Interdisciplinario de Tecnología Rural Apropiada), reduce personal exposures to CO by 78%.2 Using the Patsari stove model, Romieu et al3 reported a significantly lower FEV1 decline (31 mL) compared with open fire use (62 mL) over 1 year of follow-up (P = .012) for women 20 years of age and older. Zhou et al4 found less deterioration in FEV1 of 12, 13, and 16 mL/y in those who used biogas, improved ventilation, or both, respectively, compared with those who took up neither intervention, after adjustment for confounders. The longer the duration of improved fuel use and ventilation, the greater the benefits in slowing the decline of FEV1 (P < .05)...