Risk factors for asthma-related hospital and intensive care admissions in children, adolescents and adults: a cohort study using primary and secondary care data.

BACKGROUND: Asthma remains a common cause of hospital admissions across the life course. We estimated the contribution of key risk factors to asthma-related hospital and intensive care unit (ICU) admissions in children, adolescents and adults. METHODS: This was a UK-based cohort study using linked primary care (Clinical Practice Research Datalink Aurum) and secondary care (Hospital Episode Statistics Admitted Patient Care) data. Patients were eligible if they were aged 5 years and older and had been diagnosed with asthma. This included 90 989 children aged 5-11 years, 114 927 adolescents aged 12-17 years and 1 179 410 adults aged 18 years or older. The primary outcome was asthma-related hospital admissions from 1 January 2017 to 31 December 2019. The secondary outcome was asthma-related ICU admissions. Incidence rate ratios adjusted for demographic and clinical risk factors were estimated using negative binomial models. Population attributable fraction (PAF) was estimated for modifiable risk factors. RESULTS: Younger age groups, females and those from ethnic minority and lower socioeconomic backgrounds had an increased risk of asthma-related hospital admissions. Increasing medication burden, including excessive use of short-acting bronchodilators, was also strongly associated with the primary outcome. Similar risk factors were observed for asthma-related ICU admissions. The key potentially modifiable or treatable risk factors were smoking in adolescents and adults (PAF 6.8%, 95% CI 0.9% to 12.3% and 4.3%, 95% CI 3.0% to 5.7%, respectively), and obesity (PAF 23.3%, 95% CI 20.5% to 26.1%), depression (11.1%, 95% CI 9.1% to 13.1%), gastro-oesophageal reflux disease (2.3%, 95% CI 1.2% to 3.4%), anxiety (2.0%, 95% CI 0.5% to 3.6%) and chronic rhinosinusitis (0.8%, 95% CI 0.3% to 1.3%) in adults. CONCLUSIONS: There are significant sociodemographic inequalities in the rates of asthma-related hospital and ICU admissions. Treating age-specific modifiable risk factors should be considered an integral part of asthma management, which could potentially reduce the rate of avoidable hospital admissions.

Nocturnal temperature-controlled laminar airflow device for adults with severe allergic asthma: the LASER RCT.

BACKGROUND: Severe asthma exacerbations are costly to patients and the NHS, and occur frequently in severely allergic patients. OBJECTIVE: To ascertain whether or not nocturnal temperature-controlled laminar airflow (TLA) device usage over 12 months can reduce severe exacerbations and improve asthma control and quality of life compared with a placebo device, while being cost-effective and acceptable to adults with severe allergic asthma. DESIGN: A pragmatic, multicentre, randomised, double-blind, placebo-controlled, parallel-group, superiority trial with qualitative interviews. The trial included an internal pilot with qualitative focus groups. SETTING: Fourteen hospitals in the UK that manage patients with severe asthma. PARTICIPANTS: Adults (16-75 years) with severe, poorly controlled, exacerbation-prone asthma despite high-intensity treatment, and who are sensitised to a perennial indoor aeroallergen. INTERVENTION: Nocturnal, home-based TLA treatment using an Airsonett® (Airsonett AB, Ängelholm, Sweden) device. The comparator was a placebo device that was identical to the active device except that it did not deliver the laminar airflow. Participants were allocated 1 : 1 to TLA therapy or placebo, minimised by site, origin of case, baseline severe exacerbation frequency, maintenance oral corticosteroid use and pre-bronchodilator forced expiratory volume in 1 second. MAIN OUTCOME MEASURES: Primary outcome - frequency of severe asthma exacerbations occurring within the 12-month follow-up period, defined as worsening of asthma requiring systemic corticosteroids [≥ 30 mg of prednisolone or equivalent daily (or ≥ 50% increase in dose if on maintenance dose of ≥ 30 mg of prednisolone)] for ≥ 3 days. Secondary outcomes - changes in asthma control, lung function, asthma-specific and global quality of life for participants, adherence to the intervention, device acceptability, health-care resource use and cost-effectiveness. RESULTS: Between May 2014 and January 2016, 489 patients consented to participate in the trial, of whom 249 failed screening and 240 were randomised (n = 119 in the treatment group and n = 121 in the placebo group); all were analysed. In total, 202 participants (84%) reported use of the device for 9-12 months. Qualitative analyses showed high levels of acceptability. The mean [standard deviation (SD)] rate of severe exacerbations did not differ between groups [active 1.39 (1.57), placebo 1.48 (2.03); risk ratio 0.92, 95% CI 0.66 to 1.27; p = 0.616]. There were no significant differences in secondary outcomes for lung function, except for a reduction in mean daily peak expiratory flow [mean (SD) difference 14.7 l/minute (7.35 l/minute), 95% CI 0.32 to 29.1 l/minute; p = 0.045) for those in the active device group. There were no differences in asthma control or airway inflammation and no serious harms related to the device. No significant difference between the groups in quality-adjusted life-years gained over 1 year was observed. In addition, there was no difference in generic or disease-specific health-related quality of life overall, although statistically significant higher quality of life at month 6 was observed. Increases in quality of life were not sufficient to offset the annual costs associated with use of the TLA device. LIMITATIONS: Missing outcome data could have resulted in an underestimation of exacerbations and rendered the study inconclusive. CONCLUSIONS: Within the limits of the data, no consistent benefits of the active device were demonstrated, and the differences observed were not sufficient to make the device cost-effective. The types of patients who may benefit from the TLA device, and the reasons for large reductions in exacerbation frequency in severe asthma trials, which also incorporate other methods of recording exacerbations, need to be explored. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46346208. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 29. See the NIHR Journals Library website for further project information.

Allergies (along with viruses) are common triggers of asthma exacerbations or 'attacks', which can cause suffering and frequent visits to the general practitioner or hospital. A new machine known as a temperature-controlled laminar airflow device, which remains at the bedside and is switched on every night, filters out allergy particles in the air of a patient's breathing zone, allowing their lungs to rest in clean air overnight. We tested whether or not this machine could improve the lives of those with severe allergic asthma. We recruited 240 people across 14 centres that treat severe asthma across the UK; approximately half received the active device and the other half received a machine that looked exactly the same but did not remove the allergens (a 'placebo' machine). One in five participants was recruited using newer methods of social media such as Facebook (Facebook, Inc., Menlo Park, CA, USA) and Twitter (Twitter, Inc., San Francisco, CA, USA). Participants found the machine easy to use and to live with and there were no significant side effects. The number of attacks reduced a lot in both participants using the active device and those who used the placebo device ­ two participants in five did not suffer any attacks during the trial. However, there was no difference in the number of attacks between the two groups. This might have been because participants did not record everything that happened to them. There was no difference in measurements showing how well the lungs were working, nor in participants' quality of life after 1 year of participating in the trial. Those who were interviewed told us that the study visits and questionnaires could be burdensome, although it was helpful to think more about their asthma. An improvement was seen in one aspect of participants' breathing as well as in their quality of life after 6 months of using the machine, but these potential health benefits could not outweigh the cost of the machine.

Assessment of an accessorized pre-filled syringe for home-administered benralizumab in severe asthma.

BACKGROUND: Patients prefer at-home subcutaneous administration of biologics across different diseases, yet no biologic is approved for at-home use for severe, uncontrolled asthma. OBJECTIVE: We assessed at-home functionality, reliability, and performance of an accessorized pre-filled syringe (APFS) for subcutaneous benralizumab administration, an anti-eosinophil monoclonal antibody indicated for add-on maintenance treatment of patients with severe eosinophilic asthma. MATERIALS AND METHODS: Patients (N=116) with severe, uncontrolled asthma despite receiving medium- or high-dosage inhaled corticosteroids and long-acting ß2-agonists received up to 5 APFS-administered subcutaneous doses (Weeks 0, 4, 8, 12, and 16) of benralizumab 30 mg. The first 3 doses were administered at the study sites. The patient/caregiver administered the last 2 doses at home. Endpoints included the percentage of dispensed APFS that were used successfully blood eosinophil counts, Asthma Control Questionnaire 6, and safety. RESULTS: Nearly all dispensed APFS were successfully used in the clinic and at home (Week 0: 116/116, 100%; Week 4: 116/117, 99%; Week 8: 115/115, 100%; Week 12: 112/114, 98%; Week 16: 108/109, 99%). Only 1 APFS malfunctioned out of 573 dispensed. Two at-home administrations were unsuccessful because of patient-use error. One unreturned APFS was recorded as nonfunctional. Mean Asthma Control Questionnaire 6 scores decreased from baseline through all post-baseline time points, and nearly complete depletion of eosinophils was observed at the end of treatment. The most common adverse events were nasopharyngitis, upper respiratory tract infection, headache, and sinusitis. Five patients (4%) experienced transient mild or moderate injection-site reactions. CONCLUSION: The APFS was functional, reliable, and performed equally well in the clinic and at home.

Longterm clinical outcomes of omalizumab therapy in severe allergic asthma: Study of efficacy and safety.

Omalizumab has been shown to be an effective add-on therapy for patients with uncontrolled severe persistent allergic asthma. There has been a steady accumulation of evidence on the long-term effectiveness of omalizumab; however, data on real-life outcomes beyond one year of treatment is limited. In this study, we report on long-term outcomes of omalizumab treatment. We collected data from our severe asthma registry on hospitalisations, exacerbations, corticosteroid sparing, asthma control, lung function, biomarkers and side effects, to determine if the benefit was sustained and treatment was safe on the long term. Forty-five patients [mean age 44.9 years (range 19-69), females 37/45 (82%), mean duration of omalizumab treatment = 60.7 ± 30.9 months (range 23-121) were included in the analysis. We observed a reduction in the annual acute asthma related hospital admissions for the total population from 207 at baseline to 40 on treatment (80.7% reduction), whilst the per patient annual hospitalisations were reduced from a mean of 4.8 to 0.89 post-omalizumab treatment (p < 0.00001). There was a 76.7% reduction in daily mean maintenance OCS dose (prednisolone equivalent) from 25.8 mg (n = 43) to 6.0 mg (p < 0.0001), associated with clinically significant improvement in asthma control questionnaire (ACQ) from mean score of 4.1 (range 3.7-4.7) to 2.27 (range 0.5-4.1) p < 0.0001. The mean % predicted FEV1 has improved from 59.2% at baseline to 75.7% on treatment (p = 0.001). There was a statistically non-significant reduction in median peripheral blood eosinophils (PBE) from 300 cells/µl (range 40-1050) at baseline to 175 cells/µl (range 0-1500) post-treatment (p = 0.068), and statistically significant reduction of median fraction exhaled nitric oxide (FeNO) level from 37 parts per billion (range 12-178) to 24 ppb (range 7-50) (p = 0.0067). The work/school missed days were reduced in 17/19 patients who were at employment or school. The overall safety profile of the treatment seemed acceptable and was consistent with published experience. In conclusion, results from this real-life study demonstrate that improved outcomes in patients with severe allergic asthma are sustained with longer-term omalizumab therapy.

The cost of treating severe refractory asthma in the UK: an economic analysis from the British Thoracic Society Difficult Asthma Registry.

Severe refractory asthma poses a substantial burden in terms of healthcare costs but relatively little is known about the factors which drive these costs. This study uses data from the British Thoracic Society Difficult Asthma Registry (n=596) to estimate direct healthcare treatment costs from an National Health Service perspective and examines factors that explain variations in costs. Annual mean treatment costs among severe refractory asthma patients were £2912 (SD £2212) to £4217 (SD £2449). Significant predictors of costs were FEV1% predicted, location of care, maintenance oral corticosteroid treatment and body mass index. Treating individuals with severe refractory asthma presents a substantial cost to the health service.