A cleaner burning biomass-fuelled cookstove intervention to prevent pneumonia in children under 5 years old in rural Malawi (the Cooking and Pneumonia Study): a cluster randomised controlled trial

Abstract

SummaryBackgroundWHO estimates exposure to air pollution from cooking with solid fuels is associated with over 4 million premature deaths worldwide every year including half a million children under the age of 5 years from pneumonia. We hypothesised that replacing open fires with cleaner burning biomass-fuelled cookstoves would reduce pneumonia incidence in young children.MethodsWe did a community-level open cluster randomised controlled trial to compare the effects of a cleaner burning biomass-fuelled cookstove intervention to continuation of open fire cooking on pneumonia in children living in two rural districts, Chikhwawa and Karonga, of Malawi. Clusters were randomly allocated to intervention and control groups using a computer-generated randomisation schedule with stratification by site, distance from health centre, and size of cluster. Within clusters, households with a child under the age of 4·5 years were eligible. Intervention households received two biomass-fuelled cookstoves and a solar panel. The primary outcome was WHO Integrated Management of Childhood Illness (IMCI)-defined pneumonia episodes in children under 5 years of age. Efficacy and safety analyses were by intention to treat. The trial is registered with ISRCTN, number ISRCTN59448623.FindingsWe enrolled 10 750 children from 8626 households across 150 clusters between Dec 9, 2013, and Feb 28, 2016. 10 543 children from 8470 households contributed 15 991 child-years of follow-up data to the intention-to-treat analysis. The IMCI pneumonia incidence rate in the intervention group was 15·76 (95% CI 14·89–16·63) per 100 child-years and in the control group 15·58 (95% CI 14·72–16·45) per 100 child-years, with an intervention versus control incidence rate ratio (IRR) of 1·01 (95% CI 0·91–1·13; p=0·80). Cooking-related serious adverse events (burns) were seen in 19 children; nine in the intervention and ten (one death) in the control group (IRR 0·91 [95% CI 0·37–2·23]; p=0·83).InterpretationWe found no evidence that an intervention comprising cleaner burning biomass-fuelled cookstoves reduced the risk of pneumonia in young children in rural Malawi. Effective strategies to reduce the adverse health effects of household air pollution are needed.FundingMedical Research Council, UK Department for International Development, and Wellcome Trust.

Impact of improved cookstoves on women’s and child health in low and middle income countries: a systematic review and meta-analysis

“…Improved cookstoves had no impact on child deaths due to respiratory disease in one study (IRR 0.76 (95% CI 0.17 to 3.37)) 41. No significant impact on cough incidence or duration was observed among children in three studies,26 40 43 although in a subgroup analysis a significant reduction in cough duration was observed among girls in one study 43.…”

Quantifying the Contribution to Uncertainty in Mortality Attributed to Household, Ambient, and Joint Exposure to PM2.5From Residential Solid Fuel Use

“…The large health burden attributed to SFU has motivated interventions aimed at replacing traditional cookstoves with cleaner‐burning fuels and combustion devices (e.g., M. L. Clark et al, , ; Mortimer et al, ; Piedrahita et al, ; Ruiz‐Mercado et al, ; S. Clark et al, ); however, there are large uncertainties in the number of deaths attributed to exposure to PM 2.5 from SFU. These uncertainties originate from uncertain input parameters as well as the contribution of health risk from other ambient PM 2.5 sources.…”

Challenges in the diagnosis of paediatric pneumonia in intervention field trials: recommendations from a pneumonia field trial working group

“…Both the RESPIRE trial 10 in Guatemala and the cooking and pneumonia study 11 in Malawi show how a pneumonia case definition might fail to convey the true efficacy of a particular intervention (ie, a reduction in the amount of household air pollution). 10,11 The RESPIRE study analysed the effect of a reduction of household air pollution on pneumonia incidence in children aged between 0-18 months according to a variety of definitions, and obtained varying results.…”

“…6 Nonetheless, intervention trials have struggled to show an association between a reduction in exposure to household air pollution and decreased pneumonia incidence. 10,11 Important challenges exist in assessing pneumonia in field settings. A Comment 12 in the Lancet Global Health recognises challenges in the implementation of WHO guidelines for the management of childhood pneumonia.…”