BNT162b2 vaccine effectiveness in chronic kidney disease patients-an observational study

Abstract

Background: Chronic kidney disease (CKD) is a risk factor for severe coronavirus disease 2019 (COVID-19). We aimed to evaluate the real-life effectiveness of the BNT162b2 messenger RNA vaccine for a range of outcomes in patients with CKD compared with matched controls.

Methods: Data from Israel's largest healthcare organization were retrospectively used. Vaccinated CKD [estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m²] and maintenance dialysis patients were matched to vaccinated controls without CKD (eGFR ≥60 ml/min/1.73 m²) according to demographic and clinical characteristics. Study outcomes included documented infection with severe acute respiratory syndrome coronavirus 2, symptomatic infection, COVID-19-related hospitalization, severe disease and death. Vaccine effectiveness was estimated as the risk ratio (RR) at days 7-28 following the second vaccine dose, using the Kaplan-Meier estimator. Effectiveness measures were also evaluated separately for various stages of CKD.

Results: There were 67 861 CKD patients not treated with dialysis, 2606 hemodialysis (HD) patients and 70 467 matched controls. The risk of severe disease {RR 1.84 [95% confidence interval (CI) 0.95-2.67]} and death [RR 2.00 (95% CI 0.99-5.20)] was increased in nondialysis CKD patients compared with controls without CKD following vaccination. For the subgroup of patients with eGFR <30 ml/min/1.73 m², the risk of severe disease and death was increased compared with controls [RR 6.42 (95% CI 1.85-17.51) and RR 8.81 (95% CI 1.63-13.81), respectively]. The risks for all study outcomes were increased in HD patients compared with controls.

Conclusion: Two doses of the BNT162b2 vaccine were found to be less efficient for patients with eGFR <30 ml/min/1.73 m². Risk in HD patients is increased for all outcomes. These results suggest prioritizing patients with eGFR <30 ml/min/1.73 m² for booster shots, pre- and post-exposure prophylaxis and early COVID-19 therapy.

Keywords: BNT162b2 vaccine; COVID-19; chronic kidney disease.

Graphical Abstract

FIGURE 1:

Population flow chart describing data cleaning steps of the cohort. From an initial cohort of 3247 611 individuals >18 years of age who were insured by Clalit Health Services at the beginning of follow-up, the final cohort included 135 722 CKD nondialysis patients and 5212 dialysis patients.

FIGURE 2:

Cumulative incidence of severe infection and death related to COVID-19 in ndCKD patients according to CKD stage. Patients (red) were grouped according to eGFR and are shown compared with matched controls (blue). (A, B) Patients with CKD3A (eGFR 45 to <60 ml/min/1.73 m²), (C, D) CKD 3B (eGFR 30–<45 ml/min/1.73 m²), (E, F) patients with CKD 4–5 (eGFR 0–<30 ml/min/1.73 m²). (A, C, E) severe COVID-19 infection, (B, D, F) death related to COVID-19.

FIGURE 3:

COVID-19-related outcomes in dialysis patients following vaccination compared with matched controls. Results depict dialysis patients in red versus controls in blue; on the y-axis, cumulative incidence (%) of the specific outcome versus time (days). (A) documented infection rates, (B) symptomatic infection rates, (C) hospitalization rates, (D) severe infection and (E) death due to COVID.

FIGURE 4:

Relative risk of the various outcomes according to different stages of CKD. Patients were divided according to KDIGO eGFR based CKD stages (3A: 45 to <60 ml/min/1.73 m², 3B: 30 to <45 ml/min/1.73 m² and 4 and 5: below 30 ml/min/1.73 m²).