Cited by 191SARS-CoV-2 and COVID-19 ResearchCOVID-19 Clinical Research StudiesCOVID-19 epidemiological studies

The DOI matches its Crossref record; 9 of the 9 references it cites were found in a registry or an index; none of the 12 sources its claims cite is checked for support yet.

Case fatality risk of the SARS-CoV-2 variant of concern B.1.1.7 in England, 16 November to 5 February

Open access

Published version of a preprint

Abstract

The SARS-CoV-2 B.1.1.7 variant of concern (VOC) is increasing in prevalence across Europe. Accurate estimation of disease severity associated with this VOC is critical for pandemic planning. We found increased risk of death for VOC compared with non-VOC cases in England (hazard ratio: 1.67; 95% confidence interval: 1.34–2.09; p < 0.0001). Absolute risk of death by 28 days increased with age and comorbidities. This VOC has potential to spread faster with higher mortality than the pandemic to date.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

In England, infection with the SARS-CoV-2 B.1.1.7 variant of concern (VOC) was associated with a higher risk of death than non-VOC infection after adjustment for demographics and comorbidities (HR: 1.67; 95% CI: 1.34–2.09). Absolute 28-day death risk increased with age and comorbidities and was consistently higher for VOC across strata.

Key findings

  • In a fully adjusted Cox model, VOC infection was associated with two-thirds higher hazard of death compared with non-VOC (HR: 1.67; 95% CI: 1.34–2.09; p < 0.0001); a sensitivity analysis restricted to people testing positive at least 28 days before censoring gave HR: 1.71 (95% CI: 1.36–2.15; p < 0.0001).
  • In a fully adjusted logistic model, VOC was associated with increased odds of death by 28 days (adjusted odds ratio: 1.73; 95% CI: 1.34–2.23; p < 0.0001). Absolute risk was higher for VOC across age, sex, and comorbidity strata; the highest risk was among those aged ≥85 years with two or more comorbidities (VOC: males 24.3%, females 14.7%; non-VOC: males 16.7%, females 9.7%).
  • Among 184,786 people with known spike gene target failure (SGTF) status, there were 867 deaths (419 VOC; 448 non-VOC). The VOC group was younger and had fewer comorbidities, and median follow-up was shorter for VOC (36 days; IQR: 30–45) than non-VOC (57 days; IQR: 40–72).
  • Increased hazards for VOC were consistent across all pre-specified subgroup analyses, including epidemiological week, age group, number of comorbidities, ethnicity, and index of multiple deprivation quintile.

Methods

  • Data came from the OpenSAFELY electronic health records platform covering 40% of England’s population registered with a general practitioner, with linked GP, SARS-CoV-2 testing, vaccination, and mortality records. Cases were people testing positive for SARS-CoV-2 between 16 November 2020 and 11 January 2021, followed until death or censoring on 5 February 2021; vaccinations and diagnoses before the study period were exclusion criteria. SGTF status was known for 184,786 of 441,161 (42%) confirmed infections (91,775 VOC; 93,011 non-VOC).
  • Relative hazard of death was estimated using a Cox proportional hazards regression model stratified by upper tier local authority, with follow-up from positive test and censoring on 5 February 2021 or 7 days before vaccination. Absolute risk of death by 28 days was estimated from marginal means of a fully adjusted logistic regression model restricted to 112,979 people diagnosed at least 28 days before the censoring date, with deaths beyond 28 days censored.

Limitations

  • The paper states that people with asymptomatic or mild infection may not present for testing, so estimates of absolute risk of death by 28 days may overestimate the true case fatality ratio. It also states that SARS-CoV-2 tests performed in hospital settings in the UK are not tested for PCR S-gene target failure and are therefore not included.
  • Evident from the text: SGTF status was known for only 42% of confirmed SARS-CoV-2 infections in the study period, so the analysed population may not represent all cases. The VOC group also had shorter median follow-up than the non-VOC group, although the sensitivity analysis restricted to at least 28 days from testing to censoring was consistent.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.2807/1560-7917.es.2021.26.11.2100256

Cites

9 of 9 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Figure 1 Hazard ratios for death following diagnosis of infection with SARS-CoV-2 VOC vs non-VOC, England, 16 November 2020–5 February (n =184,786)
Figure 1 Hazard ratios for death following diagnosis of infection with SARS-CoV-2 VOC vs non-VOC, England, 16 November 2020–5 February (n =184,786)CC BY · PubMed Central
Figure 2 Excess risk of death by 28 days, SARS-CoV-2 VOC compared with non-VOC infection, England, 16 November 2020–5 February (n =112,979)
Figure 2 Excess risk of death by 28 days, SARS-CoV-2 VOC compared with non-VOC infection, England, 16 November 2020–5 February (n =112,979)CC BY · PubMed Central

Verification

Claims the paper makes

8 Not checked yet · 7 Own result · 6 Own interpretation · 5 Own method

Verify all 12 references — free account
  • It may state two separate claims as one. 7
  • Probably not a substantial claim. 7
12 of 12
  • The paper relies on this without support.

    The non-VOC comparison group represents infection with the previously circulating SARS-CoV-2 virus.

    “We found that this VOC was associated with two-thirds higher case fatality than the previously circulating virus in this unvaccinated population.”
  • The paper relies on this without support.

    The proportional hazards assumption of the Cox regression model holds.

    “using a Cox proportional hazards regression model stratified by region (upper tier local authority area (UTLA)) [4,5]”
  • The paper relies on this without support.

    The study population, drawn from the OpenSAFELY platform covering 40% of England's population registered with a GP, is representative of the wider population of England.

    “Data were drawn from the OpenSAFELY electronic health records secure research platform, covering 40% of England’s population registered with a general practitioner (GP) (see Supplement, part 1).”
  • The paper relies on this without support.

    A test result without spike gene target failure indicates non-VOC infection.

    “Spike gene target failure (SGTF) is therefore a proxy for VOC identification, with greater than 95% sensitivity for VOC diagnosis during the period from 16 November to 11 January [3].”
4 of 4

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Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

1 of 1

Citations

Cites

Show all 8 references

Research works printed but not linked: 1

  1. Cox DR, Oakes D. Analysis of survival data. London: CRC press; 1984. ISBN 9780412244902.

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Metadata

Authors
Grint, D. J., Wing, K., Williamson, E., McDonald, H. I., Bhaskaran, K., Evans, D., Evans, S. J., Walker, A. J., Hickman, G., Nightingale, E., Schultze, A., Rentsch, C. T., Bates, C., Cockburn, J., Curtis, H. J., Morton, C. E., Bacon, S., Davy, S., Wong, A. Y., Mehrkar, A., Tomlinson, L., Douglas, I. J., Mathur, R., Blomquist, P., MacKenna, B., Ingelsby, P., Croker, R., Parry, J., Hester, F., Harper, S., DeVito, N. J., Hulme, W., Tazare, J., Goldacre, B., Smeeth, L., & Eggo, R. M.
Affiliations
  • London School of Hygiene & Tropical Medicine (GB)
  • University of Oxford (GB)
  • The Phoenix Partnership (TPP), TPP House, Leeds, United Kingdom
  • The DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, United Kingdom
  • Public Health England (GB)
Corresponding author
Grint, Daniel J
Venue
Eurosurveillance
Published
2021-03-18
Volume
26
Issue
11
ISSN
  • 1025-496X (ISSN-L)
  • 1560-7917
OpenAlex
W3136104126
Cited by
189
References
8
Citations by year
2026: 1 · 2025: 3 · 2024: 13 · 2023: 18 · 2022: 68 · 2021: 85
FWCI
14.73
Type
journal article
Language
en
Open access
Locations
  • Eurosurveillance (publishedVersion, cc-by)
  • medRxiv (acceptedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • LSHTM Research Online (London School of Hygiene and Tropical Medicine) (acceptedVersion)
  • Edinburgh Research Explorer (University of Edinburgh) (submittedVersion, cc-by)
Funders
  • National Institute for Health and Care Research ((NIHR200908), MR/S003975/1, MR/V015737/1, MR/V015737)
  • Medical Research Council (MR/S003975/1, 19065, MR/R010161/1, MR/V015737/1, NIHR200908, MC_PC_19065)
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
Keywords
SARS-CoV-2, B.1.1.7 variant, variants of concern, case fatality, COVID-19 mortality, disease severity, comorbidities, age, hazard ratio, England
MeSH terms
COVID-19, SARS-CoV-2, Age Factors, England, Humans, Comorbidity

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