Enhancing ventilation in homes of children with asthma: pragmatic randomised controlled trial.

BACKGROUND Few robust studies have tested whether enhancing housing also improves health. AIM To evaluate the effectiveness of installing ventilation systems, and central heating where necessary, in the homes of children with moderate or severe asthma. DESIGN AND SETTING Pragmatic randomised controlled trial (RCT) in homes within Wrexham County Borough, Wales, UK. METHOD A pragmatic RCT was carried out, of a tailored package of housing improvements providing adequate ventilation and temperature, following inspection by a housing officer. One hundred and ninety-two children with asthma aged 5 to 14 years, identified from general practice registers, were randomised to receive this package, either immediately or a year after recruitment. At baseline, and after 4 and 12 months, parents reported their child's asthma-specific and generic quality of life, and days off school. RESULTS The package improved parent-reported asthma-specific quality of life significantly at both 4 and 12 months. At 12 months, this showed an adjusted mean difference between groups of 7.1 points (95% confidence interval [CI] = 2.8 to 11.4, P= 0.001): a moderate standardised effect size of 0.42. The generic quality-of-life scale showed reported physical problems were significantly reduced at 4 months, but not quite at 12 months, when the mean difference was 4.5 (95% CI = -0.2 to 9.1, P= 0.061). The improvement in psychosocial quality of life at 12 months was not significant, with a mean difference of 2.2 (95% CI = -1.9 to 6.4, P= 0.292). Parent-reported school attendance improved, but not significantly. CONCLUSION This novel and pragmatic trial, with integrated economic evaluation, found that tailored improvement of the housing of children with moderate to severe asthma significantly increases parent-reported asthma-related quality of life and reduces physical problems. Collaborative housing initiatives have potential to improve health.