18.05.2020

Risk factors for SARS-CoV-2 among patients in the Oxford Royal College of General Practitioners Research and Surveillance Centre primary care network: a cross-sectional study

Prognosis InfectiologyTransversal
Lusignan S et al
Lancet Infect Dis

Main result

  • 3,802 SARS-CoV-2 test results (of which 587 positive, 15.4%).
  • In multivariate analysis, these factors were independently associated with a positive test:
  •     male sex (296/1,612 males, 18.4% vs 291/ 2190 females, 13.3%): OR = 1.55; 95% CI 1.27-1.89
  •     adults compared to children, those aged 40-64 years were most at risk (243/ 1316 adults aged 40-64 years, 18.5% vs. 23/499 children, 4.6% 9 children): OR = 5.36; IC 95% 3.28-8.76
  •     people of Black ethnic origin compared to people of White ethnic origin (36/58 for people of Black ethnic origin, 62.1% vs 388/2,497, 15.5%): OR= 4.75; 95% CI 2.65-8.51
  •     people living in urban areas compared to rural areas (476/1816, 26.2% in urban areas vs. 111/1,986, 5.6% in rural areas) : OR = 4.59; IC 95% 3.57-5.90
  •     people living in the most disadvantaged areas (197/668, 29.5% in the most disadvantaged vs. 143/1,855, 7.7% in the least disadvantaged) : OR = 2.03; IC 95% 1.51-2.71
  •     individuals with chronic kidney disease (68/207, 32.9% with chronic kidney disease vs. 519/2,595 without, 14.4%): OR = 1.91; 95% CI 1.31-2.78
  •     obese people (142 [20 - 9%] out of 680 obese people versus 171 [13 - 2%] out of 1296 normal weight people; adjusted OR 1 - 41, 95% CI 1 - 04-1 - 91)

On the contrary:

  •     active smoking was associated with a decreased chance of a positive test result (47/413 active smokers, 11.4% vs 201/1,125 non-smokers, 17.9): OR = 0.49; 95% CI 0.34-0.71)

Takeaways

Risk factors for a positive outcome: similar to those observed for serious outcomes of COVID-19 in the hospital setting (including deprivation, population density, ethnicity and chronic kidney disease), with the exception of smoking.

Strenght of evidence Weak

Cohort study, n=3,802 people tested, local scale.
Exclusion of about 2.2% of the network population not wishing to share their medical data.
Multiple imputation of missing data (more than 10% missing data for BMI, smoking status, ethnic origin).
Change in practices as of March 14: self-sampling since then.

Objectives

To identify demographic and clinical risk factors for SARS-CoV-2 test positivity within the primary care network of the Royal College of Oxford Research and Surveillance Centre.

Method

Cohort study on a primary care network.

Analysis of regularly collected pseudonymized data for patients in the primary care sentinel network of the Centre for Research and Surveillance who were tested for SARS-CoV-2 between January 28 and April 4, 2020.

Inclusion of patients enrolled in a practice at the Research and Surveillance Centre as of September 30, 2019

Multivariate logistic regression model with multiple imputation to identify risk factors for SARS-CoV-2 positive tests.

bibliovid.org and its content are bibliovid property.

Legal Notice