Can Ionisers in Bedrooms Help Asthmatics?

The purpose of this double-blind, randomised, placebo-controlled cross-over study was to evaluate whether corona ionisers placed in bedrooms could improve nocturnal asthma and other symptoms in asthmatics which might be related to the indoor climate. Active or inactive (placebo) ionisers were placed in the bedrooms of 15 patients for two subsequent 4-week periods. The patients recorded daily/nightly symptoms, medication and peak expiratory flow. A histamine challenge was performed initially and after each period to measure the effect on hyperresponsiveness. Statistical analysis showed no significant differences between active and placebo periods with regard to lung function, medication, nocturnal asthma or other symptoms supposed to be related to indoor climate.