The prediction of COVID-19 and related symptoms in Lifelines

COVID-19, also known as the coronavirus, is an ongoing pandemic disease. COVID-19 can affect anyone, and the disease can cause symptoms ranging from mild to very severe. Risk factors of COVID-19 severe outcomes among hospitalized patients are older age, sex, overweight, and comorbidities such as hypertension, chronic lung disease, diabetes and coronary heart disease (Garg et al., 2020; Stefan et al., 2020; Zhou et al., 2020). There are indications that the presence of comorbidity in males is more relevant for worse outcome than in females (Walter et al., 2020; Meng et al., 2020). Older age and male sex seems independent predictors for worse outcome (Walter et al., 2020; Wang et al., 2020). In addition, about 50% of the critically ill patients are obese (Cimming et al., 2020; Stefan et al., 2020). One study observed that COVID-19 severity seems to cluster in a family (Ikitimur et al., 2020). 
Thus far, all published studies focus on in-hospital cohorts. There were no published studies on risk factors for the development of COVID-19 related symptoms among those who were tested positive for COVID19, but do not need hospitalization, or among those who had symptoms, but were tested negative. In the Lifelines cohort, weekly questionnaires are sent to participants to get an overview of COVID-19 symptoms and related burden to this pandemic disease. This gives us the opportunity to evaluate the risk factors for experiencing a COVID-19 related symptoms or a proven infection including those with a mild and severe course of COVID-19.