Abstract: SA-OR09
Clinical Efficacy of the Fourth Dose of the BNT162b2 Vaccine in Chronic Dialysis Patients
Session Information
- COVID-19 and Kidney Diseases: Mechanisms and Management
November 05, 2022 | Location: W230, Orange County Convention Center‚ West Building
Abstract Time: 05:42 PM - 05:51 PM
Category: Coronavirus (COVID-19)
- 000 Coronavirus (COVID-19)
Authors
- Shashar, Moshe, Laniado Hospital, Netanya, Central, Israel
- Grupper, Ayelet, Tel Aviv University, Tel Aviv, Israel
- Hornik-Lurie, Tzipi, Meir Medical Center, Kfar Saba, Israel
- Benchetrit, Sydney, Meir Medical Center, Kfar Saba, Israel
- Einbinder, Yael, Meir Medical Center, Kfar Saba, Israel
- Nacasch, Naomi, Meir Medical Center, Kfar Saba, Israel
- Cohen - Hagai, Keren, Meir Medical Center, Kfar Saba, Israel
Background
Following the emergence of the Omicron B.1.1.529 variant of SARS-CoV 2,Israel began on January 2,2022,to administer a fourth dose of the BNT162b2 vaccine to people 60 years and older and to at-risk populations.Chronic dialysis patients were among the first to receive the fourth dose.Given the scarcity of evidence regarding the efficacy or necessity of a fourth dose.we assessed the clinical efficacy regarding infectivity and all-cause mortality of the fourth dose of the BNT162b2 vaccine among chronic dialysis patients.
Methods
This study was conducted using the electronic database of Clalit HMO in Israel.Chronic dialysis patients receiving hemodialysis and peritoneal dialysis during the COVID-19 pandemic were included.The control group was matched in a 4 to 1 ratio to the dialysis group.The study included the pre-vaccination and post-vaccination periods.
Results
Included in this analysis were 14,230 patients of whom 2,846 were chronic dialysis patients with a mean age of 66.2±14.3 (range 18-97) years and 62.5% (1,779) were males.Mortality among unvaccinated chronic dialysis patients who tested positive for COVID-19 was 18.4%, as compared to 10.8% among similar patients who did not test positive for COVID-19 during the same period (OR 1.9, 95%CI 1.3-2.7; p=0.001).A total of 1,908 chronic dialysis patients had information available regarding vaccine status and were alive when vaccinations began in December 2020.Among them, 159 (8.3%) were unvaccinated, 113 (5.9%) were vaccinated with 1 dose, 270 (14.2%)with 2 doses, 703 (36.8%) with 3 doses, 663 (34.7%) with 4 doses.During 2022, which was dominated by the Omicron variant, 34.7% of chronic dialysis patients vaccinated with 3-doses were infected with SARS-CoV2 vs. 24.3% of 4-dose patients.Odds ratio for SARS-CoV2 infection after fourth dose was 0.6, (95%CI 0.5-0.8; p<0.001).Odds ratio for all-cause mortality in chronic dialysis patients who received 4 vs. 3 doses was 0.6 (0.4-0.9, 6.3% vs. 10.1%; p<0.001).
Conclusion
As seen in the general population,and previous vaccine boosters,the fourth dose of the BNT162b2 vaccine reduced COVID-19 infections, as well as mortality among chronic dialysis patients. Additional studies are needed to establish the exact dose and schedule of the COVID-19 vaccine in patients treated with chronic maintenance dialysis.