Rationale Household air pollution (HAP) from solid fuel combustion is a major contributor to the global burden of disease, with considerable impact from respiratory infections in children. The impact of HAP on lung function is unknown.

Objectives The Childhood Exposure to Respirable Particulate Matter (CRECER) prospective cohort study followed Guatemalan children who participated in the Randomised Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) trial of a chimney stove intervention to determine the effect of early childhood HAP exposure on growth of lung function.

Methods RESPIRE households with pregnant women or infant children were randomised to receive a chimney stove at the beginning or at the end of the 18-month trial. During CRECER, a subset of these children, as well as children from households with newly installed stoves, were followed with spirometry beginning at age 5. Biomass smoke exposure was measured using personal carbon monoxide tubes. Two-stage regression models were employed to analyse associations with lung function growth.

Measurements and main results Longitudinal peak expiratory flow (PEF) and FEV₁ data were available for 443 and 437 children, respectively, aged 5–8 (mean follow-up 1.3 years). Decreases in PEF growth of 173 mL/min/year (95% CI −341 to −7) and FEV₁ of 44 mL/year (95% CI −91 to 4) were observed with stove installation at 18 months compared with stove installation at birth in analyses adjusted for multiple covariates. No statistically significant associations were observed between personal HAP exposure and lung function.

Conclusions A significant decrease in PEF growth and a large non-significant decrease in FEV₁ growth were observed with later stove installation. Additional studies including longer follow-up and cleaner stoves or fuels are needed.