Table 2.
Regression analysis of pre- and post-messenger RNA-1273 boost log10 antispike binding antibody titers
| Independent variable | Pre-mRNA-1273 boost Bab | Post-mRNA-1273 boost Bab | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Univariable | Multivariable | Univariable | Multivariable | |||||||||
| Beta | 95% CI | P value | Beta | 95% CI | P value | Beta | 95% CI | P value | Beta | 95% CI | P value | |
| Age (per decade) | 0.095 | –0.094 to 0.283 | 0.325 | 0.019 | –0.180 to 0.219 | 0.849 | 0.111 | –0.079 to 0.301 | 0.255 | –0.001 | –0.208 to 0.205 | 0.989 |
| Gender | ||||||||||||
| Men | 0 (ref) | – | – | – | – | – | 0 (ref) | – | – | – | – | – |
| Women | –0.230 | –0.717 to 0.256 | 0.354 | –0.355 | –0.862 to 0.153 | 0.171 | –0.015 | –0.500 to 0.470 | 0.951 | 0.000 | –0.495 to 0.495 | 1.000 |
| Comorbidity | ||||||||||||
| Cardiovascular diseases | 0.418 | –0.475 to 1.310 | 0.359 | – | – | – | 1.020 | 0.158 to 1.882 | 0.020 | 0.863 | –0.064 to 1.789 | 0.068 |
| Diabetes | –0.510 | –0.251 to 1.489 | 0.617 | – | – | – | 2.360 | 0.133 to 4.587 | 0.038 | 2.106 | –0.238 to 4.449 | 0.078 |
| Obesity | 0.270 | –0.344 to 0.885 | 0.388 | – | – | – | –0.163 | –0.763 to 0.436 | 0.593 | – | – | – |
| Asthma | –0.990 | –2.316 to 0.337 | 0.144 | – | – | – | 0.377 | –1.026 to 1.780 | 0.599 | – | – | – |
| Previous SARS-CoV-2 infection, timing | ||||||||||||
| Naive vaccinated | 0 (ref) | – | – | – | – | – | 0 (ref) | – | – | – | – | – |
| Infected vaccinated | 1.489 | 0.834 to 2.144 | < 0.0001 | 1.316 | 0.545 to 2.086 | 0.001 | –0.380 | –1.024 to 0.264 | 0.248 | 0.299 | –0.478 to 1.075 | 0.451 |
| Vaccinated infected | 2.782 | 2.234 to 3.331 | < 0.0001 | 2.464 | 1.709 to 3.219 | < 0.0001 | –0.333 | –0.778 to 0.113 | 0.143 | 0.829 | 0.014 to 1.644 | 0.046 |
| Interval between first and second dose, day | –0.007 | –0.018 to 0.006 | 0.296 | – | – | – | 0.001 | –0.013 to 0.015 | 0.883 | – | – | – |
| Interval between most recent spike antigen exposure* and mRNA-1273 booster, months | ||||||||||||
| < 3 | 0 (ref) | – | – | – | – | – | 0 (ref) | – | – | – | – | – |
| 3–4 | –1.031 | –1.591 to –0.471 | < 0.0001 | –0.899 | –1.465 to –0.333 | 0.002 | 0.152 | –0.381 to 0.686 | 0.576 | 0.272 | –0.280 to 0.823 | 0.334 |
| 4–5 | –2.207 | –2.980 to –1.434 | < 0.0001 | –1.008 | –1.856 to –0.160 | 0.020 | 0.567 | –0.157 to 1.290 | 0.125 | 1.041 | 0.162 to 1.921 | 0.020 |
| 5–6 | –2.707 | –3.487 to –1.927 | < 0.0001 | –1.114 | –2.034 to –0.193 | 0.018 | 0.544 | –0.152 to 1.241 | 0.126 | 1.041 | 0.107 to 1.975 | 0.029 |
| > 6 | –2.603 | –3.300 to –1.907 | < 0.0001 | –0.840 | –1.710 to 0.031 | 0.059 | 0.932 | 0.310 to 1.553 | 0.003 | 1.576 | 0.661 to 2.491 | 0.001 |
| Preboost Bab titer | – | – | – | – | – | – | –0.191 | –0.413 to 0.032 | 0.094 | –0.135 | –0.411 to 0.140 | 0.336 |
Bab = binding antibody; mRNA = messenger RNA; ref (reference).
The table shows the results of univariable and multivariable ordinal regression analyses with preboost and postboost Bab titer as the dependent variables (classified in quartiles).
*
Defined as either CoronaVac second dose or breakthrough infection, whichever occurred most recently.