Asthma is a common respiratory disease that affects people over their lifetime. The disease affects people’s ability to breathe and if severe, to carry out normal daily activities. Asthma is classed into mild, moderate, and severe forms depending on how advanced the disease is, how frequent the symptoms occur, and how well the lungs work. People with asthma can reduce the chances of experiencing asthma attacks and disease progression by understanding and reducing their exposure to asthma triggers such as infections, cold, flu and allergies.
Pharmacological interventions can help to improve the quality of life of people with asthma. These treatments can help to reduce asthma attacks, hospital admissions and healthcare costs. Non-pharmacological treatments are equally important in managing respiratory diseases. Pulmonary rehabilitation is currently used in chronic obstructive disease (COPD) and there is increasing evidence that it can be effective in asthma too. Pulmonary rehabilitation requires people with asthma to attend a programmed exercise training and education class once or twice a week for a period of 4-weeks or more. Although pulmonary rehabilitation is recommended for use in COPD, it has not been recommended for use in asthma because of inconclusive evidence. While recent studies have suggested that the evidence of pulmonary rehabilitation in asthma is not conclusive, many of these have not had clear designs and reporting methods and have mostly had small sample sizes. In this study, we intend to use a larger sample size to assess whether pulmonary rehabilitation is effective in managing asthma.
Asthma is a chronic non-communicable respiratory disease which requires long-term management. Asthma is classified into mild, moderate, or severe based on the severity, frequency of symptoms, and lung function. For some people with asthma, the disease can be well controlled with minimal symptoms while others with uncontrolled disease may experience day to day symptoms that hinder their ability to perform day-to-day activities. Those who follow recommended treatment guidelines can experience less exacerbations, less emergency hospital admissions, and incur less healthcare costs. A recent systematic literature review suggested that there is moderate evidence that completing a pulmonary rehabilitation programme is associated with clinically meaningful improvements in exercise capacity and quality of life. While this review also concluded that pulmonary rehabilitation has minimal effect on asthma control, the certainty of evidence was low because of unclear reporting methods, small sample sizes, heterogenous study designs and interventions. Pulmonary rehabilitation is a programmed exercise training and education class attended by people with asthma once/twice a week for 4-week or more lasting at least 30 minutes per session.
This study will use routinely collected primary care data from Clinical Practice Research Datalink (CPRD) Aurum linked with Hospital Episode Statistics (APC and A&E, deprivation status (IMD) and Office of National Statistics (ONS) mortality data to investigate if pulmonary rehabilitation is associated with improvement in number of exacerbations, lung function (FEV1/FVC, FEV1 (%), FVC), MRC dyspnoea score, BMI and mortality. The study will explore these asthma outcomes comparing those who engage with pulmonary rehabilitation with those who do not. We will perform descriptive statistics using Poisson regression or negative binomial regression model with 95% confidence intervals and p-values. Causal inference analyses will be performed using inverse probability weighting (IPW) and standardization or g-formal methods.
Number of exacerbations
Lung function - FEV1/FVC, FEV1 (%), FVC,
MRC dyspnoea score,
Healthcare resource utilisation,
BMI,
Mortality
Medication use including oral corticosteroids (OCS), inhaled corticosteroids (ICS), antibiotics, long-acting beta 2-agonists (LABAs), long-acting muscarinic antagonists (LAMAs), short-acting beta-agonists (SABAs), prednisolone maintenance, montelukast, theophylline, azithromycin, antihistamine and nasal steroid.
Asthma control
Jennifer Quint - Chief Investigator - Imperial College London
Constantinos Kallis - Corresponding Applicant - Imperial College London
Ebenezar Ndachi Effiang - Collaborator - Imperial College London
HES Accident and Emergency;HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation