This is a summary, written by members of the CITF Secretariat, of:
Roushani J, Thomas D, Oliver MJ, Ip J, Yeung A, Tang Y, Brimble KS, Levin A, Hladunewich MA, Cooper R, Blake PG. Clinical Outcomes and Vaccine Effectiveness for SARS-CoV-2 Infection in People Attending Advanced CKD Clinics. CJAN. 18 April 2023;18:465-474; doi: 10.2215/CJN.0000000000000087.
The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.
A CTIF-funded study, published in the Clinical Journal of the American Society of Nephrology, showed that people with advanced Chronic Kidney Disease (CKD) who were double-vaccinated (at a time when only two doses were available) had markedly decreased fatality rates compared to CKD patients who had only one dose or no doses. The researchers note that this population had fatality rates as high as those for people on dialysis and advocate for prioritizing the vaccination of patients with advanced CKD in global efforts against COVID-19. This study was led by Dr. Peter Blake (Victoria Hospital, London Health Sciences Centre) in collaboration with Dr. Matthew Oliver and Dr. Michelle Hladunewich (both Sunnybrook Research Institute).
- The overall 30-day case fatality rate was 19%. This was highest in the first wave of COVID-19 at 29%, declining to 14% in the fourth wave.
- Risk factors for infection in advanced CKD patients included: reduced estimated glomerular filtration rate (eGFR), a measure of how well the kidneys are working; comorbidities; advanced CKD treatment for over two years; non-white ethnicity, lower income; living in the Greater Toronto Area (GTA); and residency in a long-term care home.
- Double vaccination in advanced CKD patients was shown to markedly reduce 30-day case fatality rates (but not COVID-19-related hospitalization) compared to those who were unvaccinated or had received only one dose.
This study demonstrates that while advanced CKD patients show high rates of severe outcomes after SARS-CoV-2 infection, double-vaccination reduces fatality in patients with advanced CKD. These researchers advocate for prioritization of COVID-19 vaccination in this vulnerable population. Study limitations include possible underestimation of SARS-CoV-2 infections due to the lack of routine PCR testing in patients, and a lack of generalizability to newer variants of SARS-CoV-2 or different healthcare jurisdictions.
Researchers retrospectively collected data from all patients over 18 years with advanced CKD who were treated for at least 30 days at CKD clinics in Ontario between March 1st, 2020, and November 30th, 2021. A total of 20,235 patients were included in the analysis. Clinical outcomes of severe SARS-CoV-2 infection, including case fatality rates, hospitalizations, and ICU admissions were recorded. Risk factors for infection and the association of severe disease with vaccination status were also determined.