It is not known if people with asthma are more at risk of heart problems than people without asthma. Studies carried out previously have shown mixed results. Some studies have found there is an increased chance of developing heart disease, but other studies have found that only happens in people with asthma that smoke or only in people with asthma and allergies. Therefore it may be that different people with asthma have different risks. Another study found that people in Taiwan with a similar lung disease, called chronic obstructive pulmonary disease, that had recently started an inhaled drug that is commonly used in asthma, had an increased risk of developing heart disease. Therefore, we wish to see in a UK population of people with asthma if some people have an increased risk of heart disease. Whether that increases their risk of developing heart disease, or diseases associated with heart problems, or it increases their risk of worse problems from having heart disease e.g. needing to be admitted to hospital or even dying from heart disease.
The annual incidence and mortality rates of cardiovascular disease and related diseases (ischaemic heart disease, hypertension, heart failure, ischaemic stroke, arrhythmias, thromboembolic disease, obstructive sleep apnoea and diabetes) will be calculated for people with asthma. Outcomes will be determined using primary care (CPRD), hospital diagnoses (HES) and death certificate diagnoses (ONS). Incidence and mortality will be compared to a randomly selected cohort of CPRD patients, that do not have asthma. A multivariable Poisson model, adjusted for risk factors (gender, age, smoking history, body mass index, eosinophil count, asthma medications, chronic obstructive pulmonary disease and socioeconomic status using linkage with Index of Multiple Deprivation), will be used to obtain rate ratios. To determine cardiovascular risk from long-acting bronchodilators, a nested case-control will be used from a cohort of incident long-acting bronchodilator users. Exposure (long acting bronchodilator) will be categorised by type of inhaler and duration of use. The cases will matched 1:4 and conditional logistic regression will be used to estimate the association. The same analysis will also be carried out in a COPD population.
Incidence and mortality rates of ischaemic heart disease (IHD), hypertension, heart failure (HF), ischaemic stroke, arrhythmia, thromboembolic disease, obstructive sleep apnoea and diabetes in asthma patients; incident ratios comparing to general population. Cardiovascular disease (IHD, HF, stroke, arrhythmia) risk from long-acting bronchodilators.
Chloe Bloom - Chief Investigator - Imperial College London
Chloe Bloom - Corresponding Applicant - Imperial College London
Carlos Andres Valencia Hernandez - Collaborator - Imperial College London
Freda Yang - Collaborator - Imperial College London
Rosita Zakeri - Collaborator - King's College London (KCL)
Mark Cunningham - Collaborator - Imperial College London
Varun Sundaram - Collaborator - Imperial College London
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation