Randomized Trial of Interventions to Improve Childhood Asthma in Homes with Wood-burning Stoves

• Published in: Environmental health perspectives Vol. 125; no. 9; p. 097010
• Main Authors: Noonan, Curtis W, Semmens, Erin O, Smith, Paul, Harrar, Solomon W, Montrose, Luke, Weiler, Emily, McNamara, Marcy, Ward, Tony J
• Format: Journal Article
• Language: English
• Published: United States National Institute of Environmental Health Sciences 01.09.2017; Environmental Health Perspectives
• Subjects: Air filters; Air pollution; Air Pollution - statistics & numerical data; Air pollution measurements; Air Pollution, Indoor - prevention & control; Air Pollution, Indoor - statistics & numerical data; Air quality; Air quality measurements; Allergens; Asthma; Asthma - epidemiology; Asthma - prevention & control; Biomass; Biomass burning; Burning; Care and treatment; Child; Children; Children & youth; Chronic exposure; Confidence intervals; Control methods; Cooking - instrumentation; Cooking - methods; Development and progression; Diurnal; Environmental aspects; Female; Filtration; Health aspects; Heating; Household appliances; Households; Humans; Hypersensitivity; Hypotheses; Indoor air pollution; Indoor air quality; Indoor environments; Industrialized nations; Intervention; Male; Outdoor air quality; Ovens & stoves; Particulate emissions; Particulate matter; Particulate Matter - analysis; Pediatrics; Quality of Life; Questionnaires; Respiratory tract; Rural areas; Self evaluation; Smoke; Stoves; Studies; Technology; Variability; Ventilation - methods; Wood; Wood stoves; United States > US; Montana
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/EHP849

Household air pollution due to biomass combustion for residential heating adversely affects vulnerable populations. Randomized controlled trials to improve indoor air quality in homes of children with asthma are limited, and no such studies have been conducted in homes using wood for heating. Our aims were to test the hypothesis that household-level interventions, specifically improved-technology wood-burning appliances or air-filtration devices, would improve health measures, in particular Pediatric Asthma Quality of Life Questionnaire (PAQLQ) scores, relative to placebo, among children living with asthma in homes with wood-burning stoves. A three-arm placebo-controlled randomized trial was conducted in homes with wood-burning stoves among children with asthma. Multiple preintervention and postintervention data included PAQLQ (primary outcome), peak expiratory flow (PEF) monitoring, diurnal peak flow variability (dPFV, an indicator of airway hyperreactivity) and indoor particulate matter (PM) PM2.5. Relative to placebo, neither the air filter nor the woodstove intervention showed improvement in quality-of-life measures. Among the secondary outcomes, dPFV showed a 4.1 percentage point decrease in variability [95% confidence interval (CI)=-7.8 to -0.4] for air-filtration use in comparison with placebo. The air-filter intervention showed a 67% (95% CI: 50% to 77%) reduction in indoor PM2.5, but no change was observed with the improved-technology woodstove intervention. Among children with asthma and chronic exposure to woodsmoke, an air-filter intervention that improved indoor air quality did not affect quality-of-life measures. Intent-to-treat analysis did show an improvement in the secondary measure of dPFV. ClincialTrials.gov NCT00807183. https://doi.org/10.1289/EHP849.