Comparison of COVID-19 Inactivated Virus Vaccine Immunogenicity Between Healthy Individuals and Patients on Hemodialysis: A Single-Center Study From Pakistan

Introduction This study compares the immune response after coronavirus disease 2019 (COVID-19) inactivated virus vaccine between healthy individuals (HI) and patients on hemodialysis (HD). Methods In this cross-sectional, comparative study, the presence or absence of immunoglobulin G (IgG) anti-S antibody and IgG anti-S antibody titer was compared between HI, and patients on HD after two doses of COVID-19 vaccine. Results A total of 81 participants, 50 (61.7%) HD patients and 31 (38.3%) HI, were studied. The mean age was 52.9±12 in HD patients and 42±12.4 in HI. Vaccination responder rates were 80.6% in HI and 72% in HD patients after the first dose (p=0.38) and 93.5% in HI and 94% in HD at the third week of the second dose of the vaccine (p=0.93). The mean IgG antibody titer was 156.3±113.8 in HI and 143.4 ± 117.8 in HD patients (p=0.538) after the first dose and 186.7 ± 97.9 in HI and 180.6 ± 105.8 in HD patients (p=0.552) at three weeks of the second dose. No statistically significant difference was found in antibody titer with respect to gender, age, vaccine (BBIBP-CorV or Conovac), and hypertension. Diabetic HD patients had a lower antibody titer than non-diabetic HD patients (p=0.03) while participants who had a history of COVID-19 infection had a higher IgG titer (p = 0.001). The levels of IgG titer in the same patient increased, corresponding to the doses of vaccine (p <0.001). No HD patient developed COVID-19 infection till the third week of vaccination. Conclusion This study demonstrates a similar humoral response after COVID-19 inactivated virus vaccination in HD patients and HI. The response was lower among diabetic patients on HD and better in those with previous COVID-19 infection.