Long-term immune response and antibody dynamics after SARS-CoV-2 vaccination in patients undergoing renal replacement therapy

• Published in: Paediatrics and Family Medicine 2024-01, Vol.20 (2), p.182-188
• Main Authors: Kotwica-Strzałek, Ewa, Jędrych, Ewelina, Rymarz, Aleksandra, Romejko, Katarzyna, Smoszna, Jerzy, Korsak, Jolanta, Marczak, Iwona, Gielerak, Grzegorz, Niemczyk, Stanisław
• Format: Article
• Language: English
• Subjects: Antibodies; COVID-19 vaccines; Renal replacement therapy; Severe acute respiratory syndrome coronavirus 2
• ISSN: 1734-1531; 2451-0742
• DOI: 10.15557/PiMR.2024.0026

Introduction and objective: The SARS-CoV-2 virus has triggered a global pandemic, particularly affecting individuals with comorbidities and those on renal replacement therapy. Vaccination has become a critical strategy, although evidence indicates suboptimal immunity in these groups compared to the general population. Material and methods: The study assessed the post-vaccination response in 121 patients undergoing renal replacement therapy and 104 control individuals. IgG antibody levels against glycoprotein S were measured twice: the first sample was collected 4–8 months after two vaccine doses, and the second sample 6–8 months after third dose. Results: In both groups, antibody titres significantly increased after the third vaccine dose, with no notable difference between the control and study groups after two vaccine doses (p < 0.001). The findings revealed no statistically significant difference in antibody levels between the two groups. Furthermore, there was no significant difference in infection frequency after three vaccine doses (p = 0.072). Patients who contracted COVID-19 after the third vaccination had lower antibody levels during the first blood draw, suggesting a potential impact on immunity. Among dialysis patients, a correlation was found between IgG antibody titres (in the first blood draw) and a longer time interval between the first and second vaccine doses (p = 0.021). The regression analysis indicated that a 1-unit increase in antibody level resulted in a 0.1% reduction in the risk of infection. Conclusions: The results imply that achieving immunity comparable to the general population is possible among patients undergoing renal replacement therapy more than half a year after receiving three vaccine doses. The study also introduces the hypothesis of a delayed antibody response.