TABLE 2.
SARS-CoV-2 spike S1-specific IgG antibody level and percentage responders 28 d after first vaccination (upper panel) and 28 d after second vaccination (lower panel)
| Control (N = 191) | CKD G4/5 (N = 162) | P a | Dialysis (N = 159) | P a | KTR (N = 288) | P a | |
|---|---|---|---|---|---|---|---|
| Vaccination 1 | |||||||
| Responder,b n (%) | 189 (99.0) | 156 (96.3) | 0.28 | 139 (87.4) | <0.001 | 61 (21.2) | <0.001 |
| Difference in response (%) | Ref. | 2.7% (−0.6 to 5.9) | 11.5% (6.2–16.9) | 77.8% (72.8–82.7) | |||
| S1 IgG antibody level (BAU/mL) | 435 (220–813) | 236 (104–430) | <0.001 | 105 (22–285) | <0.001 | 0.87 (0.29–6.82) | <0.001 |
| Vaccination 2 | |||||||
| Responder,b n (%) | 191 (100.0) | 162 (100.0) | – | 158 (99.4) | 0.81 | 164 (56.9) | <0.001 |
| Difference in response (%) | Ref. | – | 0.6% (−0.6 to 1.9) | 43.1% (37.3–48.8) | |||
| S1 IgG antibody level (BAU/mL) | 3186 (1896–4911) | 2405 (1287–4524) | 0.06 | 1650 (698–3024) | <0.001 | 25 (3–416) | <0.001 |
Variables are presented as mean ± SD, or as median (interquartile interval) in case of nonnormal distribution. P values are calculated using independent sample t test in case of normal distribution, Mann-Whitney U in case of nonnormal distribution and chi-squared in case of proportion.
aP values are given for the comparison between patient groups and controls and corrected for multiple testing by Bonferroni.
bSubjects were defined as responder with a level of SARS-CoV-2 Spike S1-specific IgG antibodies of ≥10 BAU/mL.
BAU, binding antibody unit; CKD, chronic kidney disease; IgG, immunoglobulin G; KTR, kidney transplant recipient; Ref., reference group; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.