RT Journal Article
SR Electronic
T1 Organ dysfunction and death in patients admitted to hospital with COVID-19 in pandemic waves 1 to 3 in British Columbia, Ontario and Quebec, Canada: a cohort study
JF CMAJ Open
JO CMAJ
FD Canadian Medical Association
SP E379
OP E389
DO 10.9778/cmajo.20210216
VO 10
IS 2
A1 Terry Lee
A1 Matthew P. Cheng
A1 Donald C. Vinh
A1 Todd C. Lee
A1 Karen C. Tran
A1 Brent W. Winston
A1 David Sweet
A1 John H. Boyd
A1 Keith R. Walley
A1 Greg Haljan
A1 Allison McGeer
A1 François Lamontagne
A1 Robert Fowler
A1 David Maslove
A1 Joel Singer
A1 David M. Patrick
A1 John C. Marshall
A1 Kevin D. Burns
A1 Srinivas Murthy
A1 Puneet K. Mann
A1 Geraldine Hernandez
A1 Kathryn Donohoe
A1 Genevieve Rocheleau
A1 James A. Russell
A1 ,
YR 2022
UL http://www.cmajopen.ca/content/10/2/E379.abstract
AB Background: There have been multiple waves in the COVID-19 pandemic in many countries. We sought to compare mortality and respiratory, cardiovascular and renal dysfunction between waves in 3 Canadian provinces.Methods: We conducted a substudy of the ARBs CORONA I study, a multicentre Canadian pragmatic observational cohort study that examined the association of pre-existing use of angiotensin receptor blockers with outcomes in adults admitted to hospital with acute COVID-19 up to April 2021 from 9 community and teaching hospitals in 3 Canadian provinces (British Columbia, Ontario and Quebec). We excluded emergency department admissions without hospital admission, readmissions and admissions for another reason. We used logistic and 0–1-inflated β regression models to compare 28-day and in-hospital mortality, and the use of invasive mechanical ventilation, vasopressors and renal replacement therapy (RRT) between the first 3 waves of the COVID-19 pandemic in these provinces.Results: A total of 520, 572 and 245 patients in waves 1, 2 and 3, respectively, were included. Patients in wave 3 were on average younger and had fewer comorbidities than those in waves 1 and 2. The unadjusted 28-day mortality rate was significantly lower in wave 3 (7.8%) than in wave 1 (18.3%) (odds ratio [OR] 0.43, 95% confidence interval [CI] 0.24–0.78) and wave 2 (16.3%) (OR 0.46, 95% CI 0.27–0.79). After adjustment for differences in baseline characteristics, the difference in 28-day mortality remained significant (adjusted OR wave 3 v. wave 1: 0.46, 95% CI 0.26–0.81; wave 3 v. wave 2: 0.52, 95% CI 0.29–0.91). In-hospital mortality findings were similar. Use of invasive mechanical ventilation or vasopressors was less common in waves 2 and 3 than in wave 1, and use of RRT was less common in wave 3 than in wave 1.Interpretation: Severity of illness decreased (lower mortality and less use of organ support) across waves among patients admitted to hospital with acute COVID-19, possibly owing to changes in patient demographic characteristics and management, such as increased use of dexamethasone. Continued application of proven therapies may further improve outcomes.Study registration: ClinicalTrials.gov, no. NCT04510623