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Risk prediction of covid-19 related death and hospital admission in adults after covid-19 vaccination: national prospective cohort study
Hippisley-Cox J, Coupland CA, Mehta N, Keogh RH, Diaz-Ordaz K, Khunti K, Lyons RA, Kee F et al.. BMJ (Clinical research ed.), 2021-09-17
Topic: Risk, prevention and care in population studies
Design Prospective, population based cohort study using the QResearch database linked to data on covid-19 vaccination, SARS-CoV-2 results, hospital admissions, systemic anticancer treatment, radiotherapy, and the national death and cancer registries. Results Of 6 952 440 vaccinated patients in the derivation cohort, 5 150 310 (74.1%) had two vaccine doses. Other conditions with increased risk (ranging from 1.2-fold to 2.0-fold increases) included chronic kidney disease, blood cancer, epilepsy, chronic obstructive pulmonary disease, coronary heart disease, stroke, atrial fibrillation, heart failure, thromboembolism, peripheral vascular disease, and type 2 diabetes. No evidence indicated that associations differed after the second dose, although absolute risks were reduced.
Key findings
- Design Prospective, population based cohort study using the QResearch database linked to data on covid-19 vaccination, SARS-CoV-2 results, hospital admissions, systemic anticancer treatment, radiotherapy, and the national death and cancer registries.
- Results Of 6 952 440 vaccinated patients in the derivation cohort, 5 150 310 (74.1%) had two vaccine doses.
- Other conditions with increased risk (ranging from 1.2-fold to 2.0-fold increases) included chronic kidney disease, blood cancer, epilepsy, chronic obstructive pulmonary disease, coronary heart disease, stroke, atrial fibrillation, heart failure, thromboembolism, peripheral vascular disease, and type 2 diabetes.
- No evidence indicated that associations differed after the second dose, although absolute risks were reduced.
Why it matters
This cohort study examined risk of covid-19 related death and hospital admission after vaccination, and lists conditions with increased risk. It does not address treating, curing, or preventing Alzheimer's disease.
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Study details
- Study designcohort study
- Effect size74.1%; 4.0%; 3.7%
- Evidence strengthModerate
How this study scored 67/100
Published in a leading specialty journal, and it is a cohort study following people over time. Scored zero for sample size, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (BMJ (Clinical research ed.)) |
| Journal's citation record | 3 / 4 | BMJ: journal h-index 413 (OpenAlex, 2026-10-29) |
| Study design | 7 / 12 | A cohort study following people over time |
| Strength of evidence | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 3 / 5 | 2021 — within 6 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 310 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 44.3 citations a year over 7 year(s) since 2021 |
| Impact for its field and year | 5 / 6 | Cited 20.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 3 / 4 | Cited 86 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Jonathan S. Nguyen‐Van‐Tam: h-index 64 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Oxford: institution h-index 2,205 (OpenAlex) |
| Multi-centre collaboration | 3 / 3 | OpenAlex lists 12 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 34535466) |
| Free to read | 2 / 2 | Free to read |
| Total | 67 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Hippisley-Cox, J., Coupland, C. A., Mehta, N., Keogh, R. H., Diaz-Ordaz, K., Khunti, K., et al. (2021). Risk prediction of covid-19 related death and hospital admission in adults after covid-19 vaccination: national prospective cohort study. BMJ (Clinical research ed.). https://doi.org/10.1136/bmj.n2244
Vancouver
Hippisley-Cox J, Coupland CA, Mehta N, Keogh RH, Diaz-Ordaz K, Khunti K, et al. Risk prediction of covid-19 related death and hospital admission in adults after covid-19 vaccination: national prospective cohort study. BMJ (Clinical research ed.). 2021. doi:10.1136/bmj.n2244. PMID: 34535466.
BibTeX
@article{hippisleycox2021-34535466,
author = {Hippisley-Cox, J. and Coupland, C. A. and Mehta, N. and Keogh, R. H. and Diaz-Ordaz, K. and Khunti, K. and Lyons, R. A. and Kee, F. and others},
title = {{Risk prediction of covid-19 related death and hospital admission in adults after covid-19 vaccination: national prospective cohort study}},
journal = {BMJ (Clinical research ed.)},
year = {2021},
doi = {10.1136/bmj.n2244},
pmid = {34535466},
url = {https://doi.org/10.1136/bmj.n2244}
}
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