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The swedish covid-19 intensive care cohort: Risk factors of ICU admission and ICU mortality
Björn Ahlström1,2, Robert Frithiof1, Michael Hultström1,3
1Anesthesiology and Intensive Care, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
Insights
Oral anticoagulants protected against intensive care unit (ICU) admission for COVID-19 patients, while certain comorbidities and RAASi treatment increased ICU admission and mortality risk. Statins were found to be protective against ICU death.
Area of Science:
- Critical Care Medicine
- Infectious Diseases
- Epidemiology
Background:
- Severe Coronavirus disease 2019 (COVID-19) risk factors require evaluation in large cohorts.
- Comorbidities and medications' roles in COVID-19 severity are not fully understood.
Purpose of the Study:
- To investigate comorbidities and medications associated with intensive care unit (ICU) admission and mortality in COVID-19 patients.
- To assess the risk of ICU admission and mortality in a matched cohort of COVID-19 patients.
Main Methods:
- Matched cohort study of COVID-19 ICU patients and population controls in Sweden.
- Conditional logistic regression and Cox proportional hazards models used to analyze risk factors.
- Data on comorbidities and medications retrieved from high-quality registries.
Main Results:
- Hypertension, type 2 diabetes, renal failure, asthma, obesity, transplant status, and immunosuppressants increased ICU admission risk; oral anticoagulants were protective.
- Stroke, asthma, COPD, and RAASi treatment were risk factors for ICU mortality; statins were protective.
- RAASi's independent risk factor status for mortality was negated after adjusting for renal replacement therapy.
Conclusions:
- Oral anticoagulants showed a protective effect against ICU admission for COVID-19.
- Statins demonstrated a protective effect against ICU mortality in COVID-19 patients.
- Comorbidities and RAASi treatment were identified as independent risk factors for ICU admission and mortality.
Background:
Several studies have recently addressed factors associated with severe Coronavirus disease 2019 (COVID-19); however, some medications and comorbidities have yet to be evaluated in a large matched cohort. We therefore explored the role of relevant comorbidities and medications in relation to the risk of intensive care unit (ICU) admission and mortality.
Methods:
All ICU COVID-19 patients in Sweden until 27 May 2020 were matched to population controls on age and gender to assess the risk of ICU admission. Cases were identified, comorbidities and medications were retrieved from high-quality registries. Three conditional logistic regression models were used for risk of ICU admission and three Cox proportional hazards models for risk of ICU mortality, one with comorbidities, one with medications and finally with both models combined, respectively.
Results:
We included 1981 patients and 7924 controls. Hypertension, type 2 diabetes mellitus, chronic renal failure, asthma, obesity, being a solid organ transplant recipient and immunosuppressant medications were independent risk factors of ICU admission and oral anticoagulants were protective. Stroke, asthma, chronic obstructive pulmonary disease and treatment with renin-angiotensin-aldosterone inhibitors (RAASi) were independent risk factors of ICU mortality in the pre-specified primary analyses; treatment with statins was protective. However, after adjusting for the use of continuous renal replacement therapy, RAASi were no longer an independent risk factor.
Conclusion:
In our cohort oral anticoagulants were protective of ICU admission and statins was protective of ICU death. Several comorbidities and ongoing RAASi treatment were independent risk factors of ICU admission and ICU mortality.
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