Health effects of ultraviolet irradiation in asthmatic children's homes

Abstract

Rationale Indoor mold exposure can aggravate allergic rhinitis/asthma. We report baseline data investigating the effect of central ultraviolet (UV) irradiation (CREON2000) in asthmatic children. Methods Twenty mold-sensitized asthmatic children aged 5–17 with central heating and ventilation systems were enrolled in a 24 week double-blinded placebo controlled cross-over trial. Subjects recorded daily indoor and outdoor AM/PM rhinitis and asthma symptom scores (SS) and peak expiratory flow rates (PEFRs). Half the homes received a sham and the other half an active CREON2000 unit. Dew point and temperature are being continuously monitored in and outdoors. At 12 weeks, active units are being exchanged for sham units and vice-versa. Air sampling for mold/bacteria and dust sampling for perennial allergens and endotoxin is being collected at baseline, crossover and completion. The primary endpoint is reduction in rhinitis/asthma exacerbations. Regression analysis will evaluate relationships between environmental exposures, symptoms, PEFRs and quality of life pre- and post-intervention. Results Patient demographics were: Avg Age=10; M:F=13:7; Cauc:AfrAm=14:6. Baseline mean biweekly total indoor rhinitis/asthma SS were 127 ± 96/77 ± 78 and outdoor rhinitis/asthma SS were 64 ± 48/40 ± 40. Baseline mean daily PEFR variability was 6%. Baseline mean outdoor/indoor mold levels were 1054 ± 1187/469 ± 850 CFU/m 3 and outdoor/indoor bacteria levels were 506 ± 1115/697 ± 618 CFU/m 3. Baseline dust analysis revealed moderate to high levels of mold allergen (μg/gm of dust) in 10/20 homes and perennial allergens in 11/20 homes. Conclusion Completion of this prospective study will determine the effect of UV irradiation on indoor mold and bacteria levels and potential health effects in asthmatic children.