Dr Sebastian Walsh

Profile

I am a public health clinical academic with a passionate interest in dementia and healthy ageing research. In 2026 I took up a Senior Clinical Lecturer post at QMUL, alongside an Honorary Consultant in Public Health post at East London NHS Foundation Trust. 

I qualified from Keele Medical School in 2015 and completed clinical foundation training in the West Midlands. I undertook academic public health specialty training in the East of England between 2018 and 2026 - which included an MPhil in Public Health at the University of Cambridge (2018-19, distinction), an NIHR Academic Clinical Fellow at Cambridge (2019-2022), an NIHR Doctoral Fellowship (2022-2025, thesis: 'A Population-Level Approach to Dementia Risk Reduction’), and placements in local, regional, and national government, Public Health England, the UK Health Security Agency, CCGs and ICBs. 

I led a 2026 national review of dementia surveillance in England on behalf of the Department of Health and Social Care and NHS England. I co-authored the 2025 Lancet Series on Alzheimer's Disease and the 2024 Lancet Commission on Dementia, co-leading on the public/population health perspectives. I co-lead the international Population-Level Approaches to Dementia Risk Reduction (PLADRR) research group. I co-chair the Academic Special Interest Group and the Healthy Ageing Special Interest Group for the UK Faculty of Public Health. I was awarded the Rising Star Award in the Alzheimer’s Society 2024 Research and Care Excellence Awards.

Research

Research Interests:

I lead public health research into dementia and healthy ageing. I use different research methods, including quantitative analyses of large datasets, qualitative work with different stakeholders, policy analysis, and complex evidence reviews. 

My current research programme focuses on compression of dementia morbidity - meaning that the period of life spent free from dementia is maximised, and the years lived with dementia (if it is to occur) are ‘compressed’ into as few years as possible at the end of life. Initial work focuses on reviewing the existing literature and developing consensus methodology for the conduct of all compression of morbidity analyses. This will be followed by application of the methodology to dementia, in order to identify dementia compressors (and expanders); as well as informing policy modelling work. I will also be undertaking both quantitative (in New Zealand) and qualitative (in the UK) work to understand the effects of compressed trajectories of decline on the experience of dementia and dementia caregiving. Broader ambitions include shifting the way that we conduct prevention analyses in the context of late-life conditions, such that systematic comparisons of disability-free years and years lived with disease become the standard approach. 

My prior research focused on population-level approaches to dementia risk reduction. This included defining the approach as a social-determinant of health based approach, empirically demonstrating it’s value, policy mapping and semi-structured interviews with policymakers to explore existing approaches and attitudes, and curation of existing population-level evidence on reducing dementia risk factors to inform quantitative modelling. All this work is published open access, and the thesis is available here: https://doi.org/10.17863/CAM.123819, with a lay summary available here: https://www.cph.cam.ac.uk/sites/default/files/dementia_prevention_summary.pdf. 

More broadly, I am interested in any aspect of the intersection of dementia/healthy ageing with public health. 

Publications

Please click through to view a full list of Sebastian's publciations

Supervision

I have an Associate Fellowship of the Higher Education Academy. 

I have supervised 3 students for their Master’s dissertations at Cambridge prior to joining QMUL in June 2026. I am an advisor to the PhD student at UCL.

I am open to supervising.