Abstract
OBJECTIVES: To evaluate anti-spike immunoglobulin G (IgG) antibody levels of hemodialysis patients and correlate them with the patients' demographic data and to evaluate these patients' need for a coronavirus disease-19 (COVID-19) vaccine booster. METHODS: A cross-sectional multi-center study carried out at King Abdulaziz Kidney Center, Hasan Tahir Hemodialysis Center, and Hayat Organization Hemodialysis Center in Al-Madinah Al-Munawarah, Saudi Arabia. Patients (n=167) who received a minimum single dose of COVID-19 vaccine were recruited. The samples were collected between March 2022 and January 2023. Anti-spike IgG antibody levels were measured using enzyme-linked immunosorbent assays. RESULTS: A significantly higher proportion of patients who received 3 doses of COVID-19 vaccine had positive serostatus compared with patients who received one or 2 doses (3 doses: 87.2%, one dose: 0.0%, 2 doses: 77.3%; p=0.000). Compared with patients who received one dose, significantly higher IgG antibody levels were detected in patients who received 2 (p=0.013) and 3 doses (p=0.025; n=35). In contrast, there was no significant difference in IgG antibody levels between patients who received 2 or 3 doses (p=0.45). Significant IgG antibody levels were detected in patients who received 2 and 3 doses (p=0.0125) compared with those received one vaccine dose (p=0.0004). Furthermore, patients who received 3 doses had significantly higher IgG antibody levels than patients who received 2 doses (p=0.000). CONCLUSION: The results show a dose-dependent association between IgG antibody levels and the number COVID-19 vaccines received. The study highlights the need for booster COVID-19 vaccination for patients on hemodialysis.