REACT Cohort Study

Context: This is an invited reapplication for 5-year Longitudinal Population Studies (LPS) infrastructural support for the REACT (REal-time Assessment of Community Transmission) Cohort Study of over 3 million participants. We respond to feedback from the Board and reviewers, and include three funding-level options as requested. Challenge: From 2020-22, the world's population experienced two unprecedented shocks: the COVID-19 pandemic exposed millions of people to a virus for which they had no prior specific immunity; and there was massive social disruption due to pandemic restrictions affecting education, work, travel, social interactions and health services. In addition, widespread vaccination was rolled out based in part on a novel technology. The short-term impacts include in the UK over 200,000 deaths by the start of 2023. Medium-term impacts are less well defined, but include ongoing symptoms and disability with Long COVID, and increased risks of cardiometabolic and other chronic diseases, while long-term impacts beyond 5 years are unknown. The REACT Cohort includes data on contemporaneous exposures/behaviours captured at scale in the community during the first two years of the pandemic, providing unique opportunity to investigate these longer term impacts. Aims and objectives: Continue to develop REACT as a resource for research into the health and social impacts of SARS-CoV-2 infection, social disruption and vaccination on the population in England. Workpackage 1 (WP1, data & sample management, discoverability & access) includes curation, archiving, storage and management of existing data and samples; wide data access via TREs, and development/maintenance of a fully integrated and operational, outward-facing 'front-end' to provide high-level functionality for researchers to interrogate summary data/metadata in real time, in tandem with implementation of the OMOP common data model led by HDR UK. WP2 (NHS data linkage) will obtain linked NHS data in Year 4 (2028-29) for participants with active consent for linkage, providing outcomes recorded through GP, hospital and registry data. WP3 (Follow-up survey including participant inclusion & retention) will undertake a further survey/cognitive assessment offered to all consented individuals during Years 4-5 (10 years post start of the pandemic), providing crucial information from participants about their lived experience, health and wellbeing which cannot be captured in routine data. We will address retention and diversity through targeted incentives and messaging. Potential applications and benefits: This LPS builds on substantial public investment from DHSC, NIHR and UKRI in the REACT programme which includes large numbers of people from groups frequently under-represented in health research. By maintaining and strengthening the REACT cohort as a major resource for the research community, we will facilitate research on the impacts of the COVID-19 pandemic on long-term physical and mental health and other outcomes including employment and disability. The extensive omic data in our clinical sub-cohort of over 10,000 people will help improve understanding of the biological pathways underlying post-COVID conditions.  We are partnering with the UK Longitudinal Linkage Collaboration (UK LLC), Population Research UK (PRUK), Health Data Research UK (HDR UK), Dementias Platform UK (DPUK) and the UK Dementia Research Institute (UK DRI), among others, to ensure we continue to adopt best practice in LPS management, that our data are widely used and available to bona-fide researchers nationally and internationally, and to secure the long-term sustainability of the cohort. We have an active public advisory panel and links to the charity Long COVID Support.