Published Articles

Published Articles

Real-world biologic use and switch patterns in severe asthma: data from the International Severe Asthma Registry and the US CHRONICLE Study

Menzies Gow, et al. J Asthma Allergy 2021; 15: 63 – 78

In this study, we investigated biologic treatment patterns for severe asthma in real-life, spanning 11 countries and 3 continents. A low rate of biologic switching was a consistent finding globally and at the country level, albeit with some inter-country variability. Despite a rapid increase in the availability of biologic therapies for asthma, 79% of the participants in our study remained on the first biologic that they were prescribed. It may be that the careful selection of an appropriate first biologic based on clinical characteristics and biomarkers resulted in inadequate clinical efficacy in the majority of patients. However, it is just as possible that reasons such as a high initial logistical, conservative threshold for a response, and limited evidence on the potential benefits of switching biologic prevented patients from switching biologic. A key finding from our study was that most switches occurred within 12 months of initial biologic prescription. Some switch patterns were associated with differing comorbidities as well, suggesting a need for clinicians to be alerted to baseline factors that would influence the subsequent decision to switch biologics.

Impact of socioeconomic status on adult patients with asthma: a population-based cohort study from UK primary care 

Busby J, et al. J Asthma Allergy 2021; 14: 1375 – 1388

In this study, we investigated the effects of socioeconomic status (SES) on clinical outcomes in a UK primary care asthma cohort (N=127,040) from the Optimum Patient Care Research Database (OPCRD). There was evidence of socioeconomic disparities, which had adverse effects on asthma outcomes. Patients from the most deprived quintile were more likely to have decreased peak flow, uncontrolled asthma, or an exacerbation during follow-up than those from the least deprived quintile, yet their rates of respiratory referrals remained comparable. This should raise clinical awareness that more deprived patients may have a greater need for specialist reviews and phenotype-targeted treatments like biologics. This study also demonstrated that the magnitude of the impact of SES on asthma outcomes was greater in patients who were older or from ethnic minority groups. Interventions to resolve socioeconomic disparities should be explored, both in the UK and globally, to improve overall asthma outcomes.

Asthma phenotyping in primary care: applying the International Severe Asthma Registry eosinophil phenotype algorithm across all asthma severities

Kerkhof M, et al. J Allergy Clin Immunol Pract 2021. 

The ISAR eosinophil phenotype gradient algorithm, when re-applied in the Optimum Patient Care Research Database (OPCRD) and Clinical Practice Research Datalink (CPRD) cohort, found that eosinophilic asthma predominates in primary care and is associated with greater asthma severity and healthcare resource utilisation. This algorithm enables primary care physicians to identify and categorise patients into those with and without eosinophilic asthma and refer them, when appropriate, for phenotype-targeted treatment.

Eosinophilic and non-eosinophilic asthma: an expert consensus framework to characterize phenotypes in a global real-life severe asthma cohort

Heaney L, et al. CHEST 2021; 160(3): 814 – 830.

In this article, we developed a multi-component, consensus-driven, and evidence-based eosinophil gradient algorithm to determine the prevalence of eosinophilic and non-eosinophilic phenotypes in the severe asthma population, and whether they can be differentiated by clinical and biomarker variables.

Cluster analysis of inflammatory biomarker expression in the International Severe Asthma Registry (ISAR)

Denton E, et al. J Allergy Clin Immunol Pract 2021; 9(7): 2680 – 2688.e7.

Allergy, eosinophilic inflammation, and epithelial dysregulation have each been implicated in severe asthma pathogenesis, and different inflammatory pathways in severe asthma may be activated to a different extent in different patients. This paper sought out to describe the interrelation between inflammatory biomarker expression in severe asthma in order to characterise the activation of underlying inflammatory pathways.

Potential Severe Asthma Hidden in UK Primary Care

Ryan D, et al. J Allergy Clin Immunol Pract 2021;9(4):1612-1623.e9.

Primary care physicians are often reticent to refer asthma patients to specialist care. The aims of this study were to identify and quantify patients with potential severe asthma (PSA) in UK primary care, the proportion not referred, and compare primary care PSA patients with confirmed severe asthma patients from UK tertiary care.

International severe asthma registry (ISAR): protocol for a global registry

FitzGerald J. M, et al. BMC Med Res Methodol 2020;20(1):212. 

Aiming to offer a rich source of real-life data for scientific research to understand and improve disease burden, treatment patterns and outcomes in patients with severe asthma, this paper describes the protocol for the development and management of the multi-disciplinary ISAR initiative.

Characterization of Severe Asthma Worldwide: Data from the International Severe Asthma Registry (ISAR)
Wang E, et al. CHEST 2020;157(4):790-804

To date, clinical characteristics of the international severe asthma population are unknown. This paper describes the demographic and clinical characteristics of patients managed in severe asthma services in the US, Europe, and Asia/Pacific region.

International Severe Asthma Registry: Mission Statement 
The ISAR Study Group. CHEST 2020;157(4):805-814

The International Severe Asthma Registry (ISAR) is the first global adult severe asthma registry. It is a joint initiative where national registries (both newly created and pre-existing) retain ownership of their own data but open their borders and share data with ISAR for ethically-approved research purposes. This paper fully describes how ISAR may improve our understanding of severe asthma.

Development of the International Severe Asthma Registry (ISAR): A Modified Delphi Study
Bulathsinhala L, et al. J Allergy Clin Immunol Pract 2019; 7(2): 578-588.e2

Getting 27 experts to agree on anything is impressive! This paper describes the process of reaching consensus on which core variables to collect in ISAR.