COVID-19 is a respiratory disease caused by infection with the virus SARS-CoV-2. The UK confirmed its first cases in January 2020 and as of the end of April 2021, had recorded more than 150,000 deaths where COVID-19 was listed on the death certificate. The widespread infection of SARS-CoV-2 in the UK has been considered an epidemic.
Chronic obstructive pulmonary disease (COPD) and asthma are common conditions of the lungs. While COPD and asthma are each distinct conditions, patients with each of these conditions can experience shortness of breath, coughing and wheezing. The impact of COVID-19 is expected to be significant and possibly long lasting, especially among patients with COPD or asthma. During the UK epidemic, patients with severe asthma and severe COPD were considered ‘clinically extremely vulnerable’ and so were asked to reduce social contact to only essential contact (termed ‘shielding’) for periods of high coronavirus prevalence.
The COVID-19 epidemic in the UK may impact patients with COPD or asthma in two ways: either indirectly where patients with COPD or asthma receive worse healthcare due to the COVID-19 epidemic, or directly where patients with asthma or COPD are diagnosed with COVID-19. This study will assess both the indirect impacts and direct impact of the COVID-19 epidemic on patients in the UK with asthma or COPD by describing both the health of these patients and the healthcare provided to these patients during and in the years surrounding the UK epidemic.
Aim: To assess the indirect and clinical impact of COVID-19 on patients with chronic obstructive pulmonary disease (COPD) and asthma in the years during and surrounding the UK COVID-19 epidemic, to inform and contextualize future research.
Objectives: For patients with asthma or COPD in the UK to describe over time: i) demographic and clinical characteristics; ii) changes in ICS dose, triple therapy use, and medication adherence; iii) factors relating to exacerbation frequency and lung function testing frequency and results; iv) all-cause, disease-related healthcare resource utilisation (HCRU) and direct medical costs; v) all-cause and COVID-19-specific mortality; vi) rate of SARS-CoV-2 infection; vii) hospitalization due to COVID-19.
Primary exposures: Treatment class, disease severity, ever diagnosed with COVID-19.
Outcomes: Change in ICS dose; Triple therapy use; Adherence; Disease-specific exacerbations; Lung function testing frequency and results; HCRU/ costs; Rate of COVID-19 diagnosis; COVID-19-related and all-cause HCRU/ costs; COVID-19-related/all-cause mortality.
Methods: A longitudinal retrospective dynamic cohort study using existing electronic primary and secondary care data of patients diagnosed with COPD or asthma. COPD and asthma cohorts will be analysed separately. The baseline period will be defined as the 12 months prior to the index date. After index, outcomes will be observed in monthly and yearly intervals until either the end of the study period, when the patients dies, or when data are no longer available.
Linked secondary care datasets will be used to describe HCRU and asthma/COPD exacerbations, and Office for National Statistics (ONS) data will be used to describe mortality.
Data Analysis: Counts, means, medians, standard deviation (SD), 25th and 75th percentile values will be reported for numeric variables, whilst relative frequencies and proportions/ percentages will be reported for nominal variables. HCRU and costs will be derived by observing consultations and medications in primary care, and Healthcare Resource Group for secondary care.
Health Outcomes to be Measured:
Change in inhaled corticosteroid dose (ICS) dose; Triple therapy use; Adherence to therapy (via proportion days covered [PDC]); Rate of COPD exacerbations; Rate of severe asthma exacerbations; FEV1% predicted (COPD cohort only); Lung function testing frequency; All-cause and COPD/asthma-related HCRU; All-cause and COPD/asthma-related direct medical costs; Rate of diagnosed COVID-19; COVID-19-related HCRU; COVID-19-related direct medical costs; All-cause/COVID-19-related mortality.
HES A&E; HES Admitted; HES Outpatient; ONS; Patient IMD