Ionisers in the management of bronchial asthma.

Abstract

ABSTRACr Because of recent interest in the possible benefits to asthmatic patients of negative ion generators and the largely uncontrolled and inconclusive nature of earlier studies a double blind crossover study of this treatment was carried out in 20 subjects with stable asthma over six months. After an initial two week period without an ioniser, active or placebo ionisers were installed in subjects' bedrooms for two eight week periods separated by a four week "washout" period when no ioniser was present. The study was completed by a final four week period when no ioniser was present. Subjects were randomly allocated to receive an active or a placebo ioniser first. Subjects recorded their peak expiratory flow rate (PEFR) twice daily, completed a daily symptom score questionnaire, and noted any treatment they took on a diary card. Recordings were completed throughout the trial. Ion counts and dust concentrations were measured in subjects' bedrooms during the study. Mean ion counts rose considerably when ionisers were activated (p < 0.001). There were no significant differences in PEFR, symptom score, or consumption of medication between the periods that active ionisers and either no ionisers or placebo ionisers were in operation. This study has failed to show a statistically significant benefit in asthmatic subjects from the use of negative ion generators.

Can Ionisers in Bedrooms Help Asthmatics?

“…Similar results were obtained in double-blind placebo-controlled cross-over studies with adult asthmatics using negative ion generators in resi dences for periods of 4-8 weeks [15,16]. In a smaller study on nocturnal asthma no clear effect was registered [17] and no difference in pulmonary function was found after exposing asthmatics to negative or positive ions for 6 h in a special room [18].…”

Decrease in the Allergenicity of Japanese Cedar Pollen Allergen by Treatment with Positive and Negative Cluster Ions

“…Previous research on the use of negative ion generators that electrostatically precipitated airborne dust and allergens has shown little or no evidence of any clinical benefits from their use [25]. Warner et al[ 26] reported that the use of ionizers could not be recommended in homes of asthmatic subjects to improve their symptoms, but that a significant abatement of airborne allergen concentrations may be useful as part of an allergen avoidance regimen.…”

“…Conflicting reports have been published about the effects of chemical expedients, carpet fresheners, acaricides, and protein-denaturing agents [17,18,19,20,21]. Physical means such as high-efficiency particulate arrest (HEPA) filter vacuum cleaners [22,23,24] and ionizers [25,26,27,28] seem to be more suitable for combating airborne allergens, but their clinical benefit is debatable. Accordingly, a combination of valid means directed at different sites seems a desirable approach, while more appropriate ways to effectively decrease the allergenic activities of airborne allergens in our living environment remain to be developed.…”

The control of allergens of dust mites and domestic pets: a position paper

“…It has been shown that exercise-induced asthma can be attenuated significantly by the exposure of patients to negatively ionized air-mean post-exercise fall in forced expiratory volume in 1 second (FEVi) was significantly less than that of a control group [142]. But double-blind cross-over studies, using active and placebo ionizers in homes, have showed no improvement of asthmatic symptoms during the period of active ionization [143], even though significant reduction in amounts of airborne Der p I during the active period was achieved in one study [82]. In this study an increase in nocturnal coughing was recorded during the active period.…”