Treatment pathways to severe asthma and health care resource utilisation in the UK

Date of ISAC Approval: 
08/02/2019
Lay Summary: 
Severe asthma refers to asthma where symptoms do not get better with the medicines that are normally given to asthma patients. Severe asthma is not very common but contributes around 50% of costs related to asthma. More research is needed to understand the true burden of severe asthma in the UK. This study will determine new asthma patients and describe their treatment journey to severe asthma. We will also describe the profile of these patients and assess the health services they use.
Technical Summary: 
Severe asthma typically refers to asthma that remains uncontrolled despite treatment with routine asthma medications such as inhaled corticosteroids and leukotriene receptor antagonists. Whilst severe asthma affects around only 5% of all patients with asthma, it is responsible for approximately 50% of the economic costs attributable to the disease, representing a severe economic burden. In addition, patients with severe asthma suffer a serious reduction in quality of life; patients have frequent Accident & Emergency (A&E) visits and are often unable to work or go to school as a result of their condition. Using a cohort of asthma patients, we will examine the treatment pathways for asthma patients to their severe asthma diagnosis and describe health care resource utilisation including referrals through to severe asthma. Such evidence will be used to highlight any unmet treatment needs and inform the current literature gap in this area.
Health Outcomes to be Measured: 
Asthma Medications (identified with gemscript codes in CPRD therapy file): - Short-acting beta-agonist - Long-acting beta-agonist - Leukotriene receptor antagonist - Oral corticosteroid - Inhaled corticosteroid - Inhaled corticosteroid / long-acting beta-agonist combination medicines - Other Asthma Exacerbations (identified with gemscript codes in CPRD therapy file, and hospital admissions recorded in primary care record [CPRD clinical and consultation files]. Should sample sizes permit and the entire sample is derived using HES, then hospitalisations will be identified using HES): - An exacerbation will be defined according to the published algorithm - A worsening of asthma requiring an A&E visit /hospital admission (i.e., the patient is admitted to the hospital with an asthma medical code) or - OCS treatment (receipt of an OCS prescription within 2 weeks of an asthma medical code) Exacerbations occurring within 7 days of the end date of OCS prescription, A&E admission, hospital discharge, or HES spell will be considered as the same exacerbation event.
Collaborators: 

Betina Blak - Chief Investigator - Astra Zeneca Ltd - UK Headquarters
Alex Simpson - Collaborator - Evidera, Inc
Annalisa Rubino - Collaborator - Evidera, Inc
Ms Clodagh Beckham - Collaborator - Astra Zeneca Inc - USA
Nafeesa Dhalwani - Corresponding Applicant - Evidera, Inc
Sharon MacLachlan - Collaborator - Evidera, Inc
Tamsin Morris - Collaborator - Astra Zeneca Ltd - UK Headquarters

Linkages: 
HES A&E;HES Admitted;HES Outpatient;Patient IMD;Practice IMD (Standard)