Table 2. Linear regression showing the predictor neutralizing antibody anti-SRBD titre 5-6 months post-vaccination (n = 76).
| Characteristic | n (%) | Mean concentration (±SD), IU/ml | Initial model | Final model | ||
|---|---|---|---|---|---|---|
| ß (95% CI) | p–value | ß (95% CI) | p–value | |||
| Post-vaccination time (month) | ||||||
| 5 (R) | 38 (50.0) | 101.8 (±102.2) | ||||
| 6 | 38 (50.0) | 95.6 (±95.2) | -30.2 (-86.8, 26.3) | 0.289 | ||
| Age (year) | ||||||
| 20-30 (R) | 34 (44.7) | 103.6 (±93.6) | ||||
| 31-40 | 26 (34.2) | 114.4 (±111.8) | -6.6 (-71.1, 57.9) | 0.838 | ||
| 41-50 | 11 (14.5) | 72.0 (±91.7) | -69.9 (-158.3, 18.5) | 0.119 | ||
| >50 | 5 (6.6) | 42.7 (±39.3) | -14.9 (-178.1, 148.2) | 0.855 | ||
| Gender | ||||||
| Male (R) | 25 (32.9) | 100.9 (±102.3) | ||||
| Female | 51 (67.1) | 97.6 (±97.1) | -3.0 (-68.6, 62.6) | 0.928 | ||
| Body mass index (BMI) | ||||||
| Underweight (R) | 8 (10.5) | 85.4 (±102.8) | ||||
| Normal | 18 (23.7) | 86.2 (±87.1) | 24.2 (-65.0, 113.4) | 0.588 | ||
| Overweight | 21 (27.6) | 92.7 (±97.8) | 47.0 (-49.8, 143.7) | 0.334 | ||
| Obesity | 29 (38.2) | 114.5 (±106.3) | 33.6 (-56.6, 123.7) | 0.459 | ||
| Regular exercise | ||||||
| Yes | 24 (31.6) | 92.4 (±98.4) | 19.2 (-45.4, 83.8) | 0.553 | ||
| No (R) | 52 (68.4) | 101.6 (±98.9) | ||||
| Sleep quality | ||||||
| Good | 27 (35.5) | 82.4 (±95.6) | -40.0 (-96.2, 16.1) | 0.159 | ||
| Poor (R) | 49 (64.5) | 107.7 (±99.4) | ||||
| Healthy meal | ||||||
| No | 49 (64.5) | 79.0 (±89.6) | -78.1 (-142.6, -13.7) | 0.018 | -62.3 (-108.5, -16.1) | 0.009 |
| Yes (R) | 27 (35.5) | 134.5 (±104.5) | ||||
| Regular food supplementation | ||||||
| Yes | 48 (63.2) | 94.4 (±95.4) | 23.0 (-32.2, 78.2) | 0.407 | ||
| No (R) | 28 (36.8) | 106.1 (±104.1) | ||||
| Smoking | ||||||
| Yes (R) | 6 (7.9) | 91.7 (±123.2) | ||||
| No | 70 (92.1) | 99.3 (±96.8) | -14.8 (-122.8, 93.3) | 0.785 | ||
| Stress level | ||||||
| Normal (R) | 66 (86.8) | 104.2 (±103.0) | ||||
| Mild | 3 (3.9) | 34.4 (±13.8) | -162.5 (-296.7, -28.2) | 0.019 | -90.6 (-203.3, 22.2) | 0.114 |
| Moderate | 3 (3.9) | 76.9 (±19.2) | -37.3 (-166.9, 92.2) | 0.566 | -48.0 (-160.7, 64.7) | 0.399 |
| Severe | 4 (5.3) | 73.2 (±65.5) | -27.5 (-139.9, 84.9) | 0.626 | -25.8 (-123.3, 71.7) | 0.599 |
| Stress | ||||||
| Yes | 10 (132) | 62.7 (±44.0) | NA (NA, NA) | NA | ||
| No (R) | 66 (86.8) | 104.2 (±103.0) | ||||
| Comorbidity | ||||||
| Hypertension | ||||||
| Yes (R) | 5 (6.6) | 45.2 (±51.7) | ||||
| No | 71 (93.4) | 102.5 (±99.8) | 66.9 (-49.8, 183.6) | 0.255 | ||
| Hyperlipidaemia | ||||||
| Yes (R) | 6 (7.9) | 23.1 (±24.9) | ||||
| No | 70 (92.1) | 105.2 (±99.4) | 55.5 (-78.2, 189.1) | 0.409 | ||
| Gout | ||||||
| Yes (R) | 6 (7.9) | 73.9 (±94.7) | ||||
| No | 70 (92.1) | 100.8 (±98.8) | 11.4 (-109.3, 132.1) | 0.851 | ||
| History of infection except COVID-19 | ||||||
| Yes (R) | 7 (9.2) | 91.7 (±85.1) | -3.2 (-93.0, 86.6) | 0.943 | ||
| No | 69 (90.8) | 99.4 (±99.9) | ||||
| Experience of vaccination side effect | ||||||
| No (R) | 39 (51.3) | 94.3 (±94.1) | ||||
| Yes | 37 (48.7) | 103.4 (±103.4) | 4.9 (-53.4, 63.2) | 0.867 | ||
| History of flu vaccination | ||||||
| Yes | 15 (19.7) | 65.5 (±69.5) | -53.0 (-117.9, 11.9) | 0.108 | ||
| No (R) | 61 (80.3) | 106.9 (±102.8) | ||||