Risk factors for developing COVID-19: a population-based longitudinal study (COVIDENCE UK)
Prospective survey-based study with 15,227 people in the UK, showing lower risk of COVID-19 cases with vitamin A, vitamin D, zinc, selenium, probiotics, and inhaled corticosteroids; and higher risk with metformin and vitamin C. Statistical significance was not reached for any of these. Except for vitamin D, the results for treatments we follow were only adjusted for age, sex, duration of participation, and test frequency. NCT04330599 (history)
. COVIDENCE UK.
The immune effects of probiotics are strain-specific.
This study is excluded in the after exclusion results of meta
significant unadjusted confounding possible.
risk of case, 30.4% lower, RR 0.70, p = 0.11, treatment 20 of 909 (2.2%), control 426 of 14,318 (3.0%), NNT 129, adjusted per study, odds ratio converted to relative risk, minimally adjusted, group sizes approximated.
Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates
Holt et al., 30 Mar 2021, prospective, United Kingdom, peer-reviewed, 34 authors, study period 1 May, 2020 - 5 February, 2021, trial NCT04330599 (history)
Abstract: Respiratory infection
Risk factors for developing COVID-19: a population-
based longitudinal study (COVIDENCE UK)
Hayley Holt,1 Mohammad Talaei ,1 Matthew Greenig,1 Dominik Zenner,1
Jane Symons,2 Clare Relton,1 Katherine S Young,3 Molly R Davies,3
Katherine N Thompson,3 Jed Ashman,1 Sultan Saeed Rajpoot,1 Ahmed Ali Kayyale,1
Sarah El Rifai ,1 Philippa J Lloyd ,1 David Jolliffe,1 Olivia Timmis,1 Sarah Finer,1
Stamatina Iliodromiti,1 Alec Miners,4 Nicholas S Hopkinson ,5 Bodrul Alam,6
Graham Lloyd-Jones ,7 Thomas Dietrich,8 Iain Chapple,8 Paul E Pfeffer ,1
David McCoy,1 Gwyneth Davies,9 Ronan A Lyons,9 Christopher Griffiths,1
Frank Kee ,10 Aziz Sheikh,11 Gerome Breen,3 Seif O Shaheen,1
Adrian R Martineau 1
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org/1 0.1136/t horaxjnl-2021-
For numbered affiliations see
end of article.
Professor Adrian R Martineau,
Blizard Institute, Barts and The
London School of Medicine
and Dentistry, Queen Mary
University of London, London
E1 2AT, UK;
HH, MT, SOS and ARM
Received 19 April 2021
Accepted 9 September 2021
© Author(s) (or their
employer(s)) 2021. No
commercial re-use. See rights
and permissions. Published
To cite: Holt H, Talaei M,
Greenig M, et al. Thorax Epub
ahead of print: [please
include Day Month Year].
Background Risk factors for severe COVID-19 include
older age, male sex, obesity, black or Asian ethnicity and
underlying medical conditions. Whether these factors
also influence susceptibility to developing COVID-19 is
Methods We undertook a prospective, population-
based cohort study (COVIDENCE UK) from 1 May 2020
to 5 February 2021. Baseline information on potential
risk factors was captured by an online questionnaire.
Monthly follow-up questionnaires captured incident
COVID-19. We used logistic regression models to
estimate multivariable-adjusted ORs (aORs) for
associations between potential risk factors and odds of
Results We recorded 446 incident cases of COVID-19
in 15 227 participants (2.9%). Increased odds of
developing COVID-19 were independently associated
with Asian/Asian British versus white ethnicity (aOR
2.28, 95% CI 1.33 to 3.91), household overcrowding
(aOR per additional 0.5 people/bedroom 1.26, 1.11 to
1.43), any versus no visits to/from other households
in previous week (aOR 1.31, 1.06 to 1.62), number of
visits to indoor public places (aOR per extra visit per
week 1.05, 1.02 to 1.09), frontline occupation excluding
health/social care versus no frontline occupation (aOR
1.49, 1.12 to 1.98) and raised body mass index (BMI)
(aOR 1.50 (1.19 to 1.89) for BMI 25.0–30.0 kg/m2
and 1.39 (1.06 to 1.84) for BMI >30.0 kg/m2 versus
BMI <25.0 kg/m2). Atopic disease was independently
associated with decreased odds (aOR 0.75, 0.59 to
0.97). No independent associations were seen for age,
sex, other medical conditions, diet or micronutrient
Conclusions After rigorous adjustment for factors
influencing exposure to SARS-CoV-2, Asian/Asian British
ethnicity and raised BMI were associated with increased
odds of developing COVID-19, while atopic disease was
associated with decreased odds.
Trial registration number C
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