An observational retrospective cohort study describing clinical outcomes and utilisation of healthcare resources among persons with COVID-19 in England, stratified by infection severity and selected comorbidities

Study type
Protocol
Date of Approval
Study reference ID
21_000737
Lay Summary

The size of the population in England for whom the COVID-19 vaccination may not work as well is not well-understood; similarly, as COVID-19 is still a new phenomenon, relatively little is known concerning the impact of COVID-19 infection on patients’ interactions with the healthcare system as well as associated costs of care. This study aims to describe the size of populations in England who are potentially ineligible for COVID-19 vaccines or who are at an increased risk of severe COVID-19 infection following vaccination. This study additionally will describe the occurrence of COVID-19 infection and associated interactions with the healthcare system and cost of care both before and after vaccination in England. It is anticipated that findings from this study will: (1) enhance our understanding of the potential impact of COVID-19 vaccines amongst vulnerable populations; (2) help quantify the pre-vaccine healthcare costs of COVID-19 infection, thereby providing the necessary context for any assessment of potential reduction in healthcare burden following vaccination; and (3) help increase knowledge of the disease in terms of disease severity and prognosis.

Technical Summary

This is a retrospective cohort study describing clinical outcomes and utilization of healthcare
resources and associated costs among persons with COVID-19 using Clinical Practice Research Datalink (CPRD) Aurum linked to HES, CHESS, SACT) and ONS deaths data.
Objective 1 of this study is to estimate the size of populations (n, %) in England who
potentially are ineligible for vaccine or are at risk of COVID-19 infection following vaccination. The study population for objective 1 will include all pre-defined patient subgroups considered to be potentially ineligible for COVID-19 vaccines or are at risk of COVID-19 infection following vaccination, due to contraindications, limited safety data available, and/or elevated risk of suboptimal response. The second objective is to estimate incidence of COVID-19, by age group, disease severity, and selected comorbidities. This will be measured by calculating infections per 100 person-months and 95% confidence intervals. The third objective is to estimate incidence of long COVID-19 syndrome, by age, disease severity, and selected comorbidities. This will be measured by proportion of patients (n, %) with long COVID-19 syndrome as well as by infections per 100 person-months and 95% confidence intervals. The fourth objective is to describe patterns of HCRU and cost associated with COVID -19 infection, stratified by age, selected comorbidities, disease severity and the occurrence (vs. absence) of long COVID-19 syndrome.
This study is expected to benefit the public health of England by providing an updated estimate on the incidence of COVID-19 and long COVID-19 for vulnerable patient groups, associated healthcare resource utilization, and direct medical costs. This will also provide essential information for cost-effectiveness assessment needed by health technology assessment agencies in the UK and other countries to decide whether or not additional therapeutics are needed and should be approved for prevention and treatment of COVID-19.

Health Outcomes to be Measured

• Size of the population: the size of the populations that are ineligible for COVID-19 vaccinations or at increased risk of COVID-19 infections following vaccination.
• COVID-19 infections: new COVID-19 infections.
• Long COVID-19: patients who have developed long COVID-19. .
• Health care resource use and associated costs: inpatient visits, hospital length of stay, days mechanically ventilated, days in intensive care, outpatient visits, specialist outpatient visits, primary care visits, primary care referrals, prescriptions, procedures and direct cost of care associated with COVID-19 infections.

Collaborators

Sabada Dube - Chief Investigator - AstraZeneca Ltd - UK Headquarters
Sophie Graham - Corresponding Applicant - Evidera, Inc
Christen Gray - Collaborator - AstraZeneca Ltd - UK Headquarters
Clement Erhard - Collaborator - AstraZeneca Ltd - UK Headquarters
Eleni Rapsomaniki - Collaborator - AstraZeneca Ltd - UK Headquarters
Kathryn Evans - Collaborator - Evidera, Inc
Nahila Justo - Collaborator - Evidera Ltd - UK
Renata Yokota - Collaborator - AstraZeneca Ltd - UK Headquarters
Sabada Dube - Collaborator - AstraZeneca Ltd - UK Headquarters
Sofie Arnetorp - Collaborator - Astra Zeneca R&D Molndal Sweden
Sylvia Taylor - Collaborator - AstraZeneca Ltd - UK Headquarters
Xiaojian Chen - Collaborator - Astra Zeneca Inc - USA
Yi Lu - Collaborator - Evidera, Inc

Linkages

CHESS (Hospitalisation in England Surveillance System);HES Accident and Emergency;HES Admitted Patient Care;HES Diagnostic Imaging Dataset;HES Outpatient;NCRAS Cancer Registration Data;NCRAS Systemic Anti-Cancer Treatment (SACT) data;ONS Death Registration Data;Practice Level Index of Multiple Deprivation;COVID-19 Linkages