Effectiveness of Air Filters and Air Cleaners in Allergic Respiratory Diseases: A Review of the Recent Literature

Air filtration is frequently recommended as a component of environmental control measures for patients with allergic respiratory disease. Residential air filtration can be provided by whole house filtration via the home’s heating, ventilation, or air conditioning system, by portable room air cleaners, or a combination of the two. Appliances to filter the sleep breathing zone also have been developed. High-efficiency whole house filtration, high-efficiency particulate air sleep zone air filtration, and high-efficiency particulate air room air cleaners all appear to provide various degrees of benefit. Recent studies of various types of filtration, used alone or as part of more comprehensive environmental control measures, are reviewed

Clinical effects of purified air administered to the breathing zone in allergic asthma: A double-blind randomized cross-over trial

SummaryBackgroundExposure to inhaled allergens is a pathogenetic factor in allergic asthma. However, most studies that previously looked at air cleaning devices have shown little or no effect on patients with perennial allergic asthma.Aims and objectivesWe examined a novel treatment using temperature regulated laminar airflow with a very low particle concentration directed to the breathing zone of teenagers and young adults with mild to moderate allergic asthma during night sleep. We hypothesised that the decreased allergen exposure during the night would have an effect on bronchial inflammation and quality of life.MethodTwenty-two patients (mean 18.8years) were randomized to start with active or placebo treatment for 10weeks. All patients received both active and placebo treatment with unfiltered air, with a 2-week wash-out period in between treatments. Maintenance treatment with inhaled corticosteroids was unaltered during the trial period. Health related quality of life (miniAQLQ) was the primary effectiveness measure. Exhaled nitric oxide (FeNO) and spirometry were also investigated.ResultsActive treatment resulted in an improved miniAQLQ compared to placebo (mean score 0.54, p<0.05, n=20). An effect on bronchial inflammation was also detected with significantly lower FeNO values during the active treatment period (mean −6.95ppb, p<0.05, n=22). Both effects were evident after 5weeks. The change in lung function was not statistically significant.ConclusionClean air, administered directly to the breathing zone during sleep, can have a positive effect on bronchial inflammation and quality of life in patients with perennial allergic asthma

Peripheral nitric oxide is increased in rhinitic patients with asthma compared to bronchial hyperresponsiveness.

Allergic rhinitis is a predisposing factor for developing clinical asthma. Moreover, allergic rhinitis is often associated with bronchial hyperresponsiveness (BHR). We hypothesise that patients with asthma have more small airway involvement than those with allergic rhinitis and BHR alone. The aim of this study was to assess peripheral and proximal NO concentration in rhinitic subjects, and to correlate the peripheral NO concentration to the peripheral obstruction in response to methacholine. Patients with allergic rhinitis with or without BHR, or clinical asthma were investigated in and out of the allergy season. Healthy subjects served as controls. Fractional exhaled NO was performed, and peripheral NO concentration and proximal flux of NO was calculated. Methacholine test was performed including impulse oscillometry. Rhinitic patients with asthma demonstrate an increase in both proximal and peripheral NO compared to those with rhinitis atone or those with BHR. There is a trend of increased peripheral NO from patients with rhinitis only, rhinitis and BHR, to rhinitis with asthma. The increase in peripheral NO correlated with an increased peripheral obstruction in response to methacholine. Patients with seasonal allergic rhinitis demonstrated a decrease in both proximal and peripheral NO in the off-season. The results support our hypothesis that rhinitic patients with asthma have more peripheral lung inflammation and small airway involvement compared to rhinitic patients with BHR alone

The Swedish National Airway Register (SNAR) : development, design and utility to date

Background: The Swedish National Airway Register (SNAR) was initiated in 2013 to ensure and improve the quality of care for patients with asthma and COPD. Aim: To describe the development and design of SNAR, and to study the 2019 data to evaluate its potential utility related to improvement of quality of care. Methods: SNAR includes data from patients with asthma (both children and adults) and COPD from primary, secondary and tertiary care, and also, for COPD inpatient care. Data on diagnostic investigations (e.g. spirometry, blood sample, skin prick test), symptom-scores, comorbidities and prescribed treatments are registered. The registrations are entered manually by healthcare professionals, or directly transferred from electronic medical records to a web-based platform. Results: In 2019, 1000 clinics participated and data were directly transferred by about 88% of them. The register included data on 205,833 patients with asthma and 80,372 with COPD (of these, 5% had both diagnoses). Registrations of new patients and follow-up visits from primary and secondary/tertiary care in 2019 were completed for 75,707 patients with asthma (11,818 children &lt;12 yr, 6545 adolescents 12–17 yr, and 57,344 adults &gt;17 yr) and 38,117 with COPD. Depending on age and disease group, 43–77% had performed spirometry, 36–65% Asthma Control Test, and 60% COPD Assessment Test. The prevalence of current smoking was about 2% in adolescents, 10% in adults with asthma, and 34% in COPD. For these, smoking cessation support was offered to 27%, 38% and 51%, respectively. Overall, limited data were available on investigation of allergy, 6-min walk test, patient education and written treatment plans. Regarding asthma, sex-differences in disease management were evident. Conclusion: SNAR has cumulatively registered data from over 270,000 individuals, and the register is important for patients, caregivers, authorities, politicians and researchers to evaluate the effect of treatment and to ensure high and equal quality of care nationwide

Assessment of problematic severe asthma in children.

Assessment of problematic severe asthma in children should be performed in a step-wise manner to ensure an optimal approach. A four-step assessment scheme is proposed. First, a full diagnostic work-up is performed to exclude other diseases which mimic asthma. Secondly, a multi-disciplinary assessment is performed to identify issues that may need attention, including comorbidities. Thirdly, the pattern of inflammation is assessed, and finally steroid responsiveness is documented. Based upon these four steps an optimal individualised treatment plan is developed. In this article the many gaps in our current knowledge in all these steps are highlighted, and recommendations for current clinical practice and future research are made. The lack of good data and the heterogeneity of problematic severe asthma still limit our ability to optimise the management on an individual basis in this small, but challenging group of patients