Burden and prevalence of prognostic factors for severe covid-19 disease in Sweden

Katalin Gemes; Mats Talback; Karin Modig; Anders Ahlbom; Anita Berglund; Maria Feychting; Anthony Matthews

All calculations from the main analyses rest on the assumption that any medical conditions were diagnosed within three years prior to 1 st January 2016. We have also presented the same analyses when the look back period is changed to one, five and ten years. The primary look back period was defined as three years due to being a reasonable time frame to capture individuals with active disease. We believe that this is a fair assumption and gives an accurate overview of the burden of disease in the population for all diseases apart from cancer. It has been suggested that only those with active cancer are truly at a high risk of severe COVID-19, and a definition of active cancer can take many forms. [32] Three years can be considered a long time after cancer diagnosis, and if the individual has survived, it is likely they will be considered to no longer have active cancer at three years after diagnosis. Therefore, for cancer, the analysis with a one year look back period may be a better estimation of individuals with active disease.