Background

Desert dust storm (DDS) events have been associated with increased morbidity among children with asthma. The MEDEA randomised trial assessed the impact of indoor air filtration and other exposure reduction recommendations on asthma symptom control, lung function and airway inflammation among children with asthma during high DDS season in Cyprus and Greece.

Methods

Schoolchildren with asthma aged 6-11 years were randomised into three groups: (a) No Intervention (controls) (b) Outdoor Intervention (early warning dissemination, guidance to stay indoors and limit outdoor physical activity), (c) Combined Intervention (same as (b) in combination with indoor air purification in households and classrooms. Monthly asthma symptom control was quantified using the childhood Asthma Control Test (c-ACT), while lung function (FEV1, FVC) and Fractional exhaled Nitric Oxide (FeNO) assessments were carried out at the start, middle and end of the study period.

Results

A total of 182 children with asthma (mean age: 9.5 years) completed the study. By the end of the study period and compared to controls, the combined intervention group demonstrated a statistically significant improvement in cACT (β:2.63, 95%CI: 0.61-4.65, p:0.011), FEV1% predicted (β:4.26, 95%CI: 0.35-8.17, p:0.033) and FVC1% predicted (β:3.88, 95%CI: 0.11-7.64, p:0.044). The change in FeNO did not reach statistical significance between the three groups.

Conclusion

During the high DDS season, exposure reduction recommendations, especially those employing indoor air purification, were associated with improved cACT and lung function in children with asthma.