Since the beginning of the Covid-19 pandemic, the scientific community has explored determinants of Covid 19 disease severity. However, the majority of studies are based on in-hospital patients with high risk of collider- or selection bias. The present investigation details risk factors associated with overall mortality, hospitalization and intensive care unit (ICU) admission in Covid-19 infections, with complete population coverage and high-resolution data on patient characteristics and comorbid conditions This population-based observational study comprises all residents 18 years and older in Stockholm Region—1.8 million inhabitants—using the real-time Covid-19 monitoring framework. The observation period lasted between March 1 to December 31, 2020. Hazard ratios (HR) for risk factors of Covid-19 disease severity were assessed using Cox proportional hazard models. In total, 3322 deaths, 11,508 hospitalizations and 1423 ICU-admissions related to Covid-19 occurred during the study period. Kidney failure, diabetes and obesity increased risk of mortality and so did heart failure and ischemic heart disease. However, atrial fibrillation and hypertension did not. Risk of hospitalization follow a similar pattern, whereas admission to intensive care differs; triage processes where clearly present as certain co-morbid conditions were associated with lower ICU admission. Observed differences in risk of mortality and hospitalization among patients with Covid 19 raise important questions about potentially protective comedication which will be further addressed using the real-time Covid-19 monitoring framework.

自 Covid-19 大流行开始以来，科学界一直在探索 Covid-19 疾病严重程度的决定因素。然而，大多数研究都是基于具有高碰撞偏倚或选择偏倚风险的住院患者。本调查详细介绍了与 Covid-19 感染的总体死亡率、住院治疗和重症监护病房 (ICU) 入住相关的风险因素，并提供完整的人群覆盖以及有关患者特征和合并症的高分辨率数据这项基于人群的观察性研究包括所有居民斯德哥尔摩地区 180 万名居民中 18 岁及以上的居民使用实时 Covid-19 监测框架。观察期持续2020年3月1日至12月31日。使用Cox比例风险模型评估Covid-19疾病严重程度危险因素的风险比（HR）。研究期间，总共有 3322 人死亡，11,508 人住院，1423 人入住 ICU。肾衰竭、糖尿病和肥胖会增加死亡风险，心力衰竭和缺血性心脏病也会增加死亡风险。然而，房颤和高血压却没有。住院风险遵循类似的模式，但入住重症监护室的风险不同；分诊过程明显存在某些共病状况与较低的 ICU 入院率相关。观察到的 Covid-19 患者死亡和住院风险的差异引发了有关潜在保护性药物治疗的重要问题，这一问题将使用实时 Covid-19 监测框架进一步解决。