Characteristics and outcomes of patients admitted to Swedish intensive care units for COVID-19 during the first 60 days of the 2020 pandemic: a registry-based, multicenter, observational study

Abstract

Background The mortality of patients admitted to the intensive care unit (ICU) with COVID-19 is unclear due to variable censoring and substantial proportions of undischarged patients at follow-up. Nationwide data have not been previously reported. We studied the outcomes of Swedish patients at 30 days after ICU admission. Methods We conducted a registry-based cohort study of all adult patients admitted to Swedish ICUs from 6 March-6 May, 2020 with laboratory confirmed COVID-19 disease and complete 30-day follow-up. Data including baseline characteristics, comorbidities, intensive care treatments, organ failures and outcomes were collected. The primary outcome was 30-day all-cause mortality. A multivariable model was used to determine the independent association between potential predictor variables and the primary outcome. Results A total of 1563 patients were identified. Median ICU length of stay was 12 (5-21) days, and fifteen patients remained in ICU at the time of follow-up. Median age was 61 (52-69), median Simplified Acute Physiology Score III (SAPS III) was 53 (46-59), and 66.8% had at least one comorbidity. Median PaO2/FiO2 on admission was 97.5 (75.0-140.6) mmHg, 74.7% suffered from moderate to severe acute respiratory distress syndrome (ARDS). The 30-day all-cause mortality was 26.7%. The majority of deaths occurred during ICU admission. Age, male sex (adjusted odds ratio [aOR] 1.5 [1.1-2.1]), SAPS III score (aOR 1.3 [1.2-1.4]), severe ARDS (aOR 3.1 [2.0-4.8], specific COVID-19 pharmacotherapy (aOR 1.4 [1.0-1.9]), and CRRT (aOR 2.2 [1.6-3.0]), were associated with increased mortality. With the exception of chronic lung disease, the presence of comorbidities was not independently associated with mortality. Conclusions Thirty-day mortality rate in COVID-19 patients admitted to Swedish intensive care units is generally lower than previously reported. Mortality appears to be driven by age, baseline disease severity, the degree of organ failure and ICU treatment, rather than preexisting comorbidities.

Characteristics, management and survival of ICU patients with coronavirus disease‐19 in Norway, March‐June 2020. A prospective observational study

“…Age, diabetes and chronic kidney disease were all independently associated with mortality. Notably, however, the median age of our population was 63 years, similar to that observed in Italy 13 and intermediate of that observed in Denmark (68 years) 33 and Iceland (64 years), 34 and that found in Sweden (61 years), 35 and the UK (60 years). 32 It should be noted that admission to intensive care of nursing home residents is rarely deemed appropriate in Norway.…”

Severe COVID-19 among patients with asthma and COPD: a report from the Swedish National Airway Register

“…Data extraction from SNAR was conducted on August 17, 2020, and linked with data from the NPR (inpatient care), the Swedish Intensive Care Registry (SIR), and the Swedish Cause of Death Register (SCDR) on 11 September. 11 , 17 These registers provide data about COVID-19 based on International Classification of Diseases, version 10 (ICD-10) codes U07.1 (COVID-19 confirmed by laboratory testing) and U07.2 (COVID-19 clinically or epidemiologically diagnosed, but laboratory testing is inconclusive or not available). The registration of inpatient care, intensive care and causes of death have coverage of nearly 100%.…”

“…The registration of inpatient care, intensive care and causes of death have coverage of nearly 100%. 11 , 17 A severe COVID-19 was defined as hospitalization (inpatient care identified as primary discharge diagnosis in NPR and/or ICU registration in SIR) or death due to COVID-19 (registered as an underlying or contributing cause of death in SCDR). Patients in SNAR with severe COVID-19 were defined as cases and patients in SNAR without severe COVID-19 as controls.…”

“… 9 , 10 In Sweden, the proportion of patients with chronic lung diseases was 14% in the intensive care units (ICU) during the first months of the pandemic. 11 …”

“…9,10 In Sweden, the proportion of patients with chronic lung diseases was 14% in the intensive care units (ICU) during the first months of the pandemic. 11 Overall, asthma patients do not seem to represent a risk group, 12 chronic obstructive pulmonary diseases (COPD), on the contrary, has shown to be associated with an increasing need for intensive care treatment and risk of death. 13 However, most studies are based on patients with COVID-19 identified with asthma or COPD as comorbidities, rather than settings using high-quality nationwide registers for identification of COVID-19 in patients with obstructive lung diseases.…”