Source : medRxiv
Auteurs : Elizabeth Williamson and al.
“Voici une étude britannique, qui a été reprise largement dans les médias. Elle s’intéresse aux facteurs de risque de décéder (à l’hôpital) du COVID en population générale. Échantillon de plus de 17 000 000 d’adultes adhérents au NHS (Angleterre), avec un peu plus de 5000 décès intra-hospitaliers attribués au COVID-19. On y retrouve les facteurs de risque classiques, mais aussi, de façon originale, la précarité (sur la base de la zone géographique) et l’appartenance à un groupe ethnique autre que « blanc ». Une étude « big data », qui ne prend en compte que les décès intra-hospitaliers et ne donne pas d’informations sur le risque de contracter la pathologie : elle mélange « risque de contracter la maladie » et « risque de décéder une fois infecté » présenté par le Dr Marie MOITRY
Background: Establishing who is at risk from a novel rapidly arising cause of death, and why, requires a new approach to epidemiological research with very large datasets and timely data. Working on behalf of NHS England we therefore set out to deliver a secure and pseudonymised analytics platform inside the data centre of a major primary care electronic health records vendor establishing coverage across detailed primary care records for a substantial proportion of all patients in England. The following results are preliminary.
Data sources: Primary care electronic health records managed by the electronic health record vendor TPP, pseudonymously linked to patient-level data from the COVID-19 Patient Notification System (CPNS) for death of hospital inpatients with confirmed COVID-19, using the new OpenSAFELY platform.
- Population: 17,425,445 adults.
- Time period: 1st Feb 2020 to 25th April 2020.
- Primary outcome: Death in hospital among people with confirmed COVID-19.
Methods: Cohort study analysed by Coxregression to generate hazard ratios: age and sex adjusted, and multiply adjusted for covariates selected prospectively on the basis of clinical interest and prior findings.
Results: There were 5683 deaths attributed to COVID-19. In summary after full adjustment, death from COVID-19 was strongly associated with: being male (hazard ratio 1.99, 95%CI 1.88-2.10); older age and deprivation (both with a strong gradient); uncontrolled diabetes (HR 2.36 95% CI 2.18-2.56); severe asthma (HR 1.25 CI 1.08-1.44); and various other prior medical conditions. Compared to people with ethnicity recorded as white, black people were at higher risk of death, with only partial attenuation in hazard ratios from the fully adjusted model (age-sex adjusted HR 2.17 95% CI 1.84-2.57; fully adjusted HR 1.71 95% CI 1.44-2.02); with similar findings for Asian people (age-sex adjusted HR 1.95 95% CI 1.73-2.18; fully adjusted HR 1.62 95% CI 1.43- 1.82).
Conclusions: We have quantified a range of clinical risk factors for death from COVID-19, some of which were not previously well characterised, in the largest cohort study conducted by any country to date. People from Asian and black groups are at markedly increased risk of in-hospital death from COVID19, and contrary to some prior speculation this is only partially attributable to pre-existing clinical risk factors or deprivation; further research into the drivers of this association is therefore urgently required. Deprivation is also a major risk factor with, again, little of the excess risk explained by co-morbidity or other risk factors. The findings for clinical risk factors are concordant with policies in the UK for protecting those at highest risk. Our OpenSAFELY platform is rapidly adding further NHS patients’ records; we will update and extend these results regularly.