Factors predictive of anti-spike antibody titers after COVID-19 vaccination in hemodialysis patients

Abstract

Background. Hemodialysis (HD) patients have a high prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mortality, but they may have a weak response to coronavirus disease 2019 (COVID-19) vaccines.Objectives. This study aimed to evaluate factors predictive of humoral response in HD patients vaccinated against SARS-CoV-2 infection. Materials and methods. This is a 2-center observational study including HD patients who received the BNT162b2 mRNA vaccine followed by serological measurements 20 days and 4 weeks after the 1 st and 2 nd dose, respectively. Healthy controls were included. Anti-spike antibody was measured using the chemiluminescent immunoassay (CLIA) method. The quantile regression analysis was performed to assess factors associated with anti-spike antibody titers.Results. Seventy-two HD patients and 22 healthy controls were included. Mean age of dialysis patients and controls was 72.5 ±11.5 years and 45.7 ±17.4 years, respectively. In the HD group, median levels of anti-spike antibody were 3 (interquartile range (IQR): 0.5−26) UI/mL and 391 (IQR: 55−1642) UI/mL after the 1 st and 2 nd dose, respectively, with response rates of 62.5% and 96.7%. The median level of the anti-spike antibody after the 1 st dose in previously infected patients was 8571 (IQR: 2586−19147) UI/mL. There was a significant correlation between anti-spike antibody levels after the 2 nd dose and age and anti-hepatitis B surface (HBs) antibody and serum albumin levels (Spearman's rho: r = −0.289, p < 0.001; r = 0.357, p = 0.027; r = 0.317; p = 0.026, respectively). The regression analysis showed a significant association of previous infection and anti-Hbs antibody level with anti-spike antibody level after the 1 st dose of vaccine (p < 0.001). After a 5-month follow-up, 2 vaccinated patients contracted COVID-19.Conclusions. This study showed a response rate of 96.7% to 2 doses of BNT162b2 mRNA vaccine in HD patients and 100% to a single dose in previously infected patients. The level of anti-spike antibody can be predicted by age, anti-Hbs antibodies, serum albumin, and previous infection. Despite the immunization of patients, preventive measures should be maintained in all dialysis units.

Untitled

“…The study from Myanmar, antibody response was positively related with BMI in health care worker [30]. The patients with previous covid-19 infection had higher median anti-Spike antibody level, 4400 U/mL than the patients without previous infection 1680 U/mL; it confirmed the former reports though statistically not significant in this study [14,31]. This finding was similar to that of normal population; infected vaccinated participants had superior antibody levels across time compared to naïve-vaccinated people [32][33][34].…”

“…Reported clinical predictors of antibody positive response toward COVID-19 vaccination were age, previous infection [14], immunosuppressive therapy, body mass index, iron deficiency anemia [15,16] and serum albumin level [14]. Longer vintage of end-stage kidney disease, and lower pre-vaccination serum albumin were related with response to vaccine in patients on MHD [17].…”