Table 2.
GMTs and fold increases of HI antibodies for three influenza strains in the RA treatment groups prior to and after influenza vaccination
| MTX group (n=65) | TCZ+MTX group (n=49) | TCZ group (n=62) | RA control group (n=18) | p Values between treatment groups | |
|---|---|---|---|---|---|
| GMTs | |||||
| A/H1N1 | |||||
| Before | 31.7 (16.1–47.2) | 59.5 (19.9–99.1) | 62.0 (25.4–125.4) | 15.3 (8.3–22.3) | NS |
| After | 120.5 (75.3–165.6)* | 162.1 (86–238.2)** | 211.7 (142–281.4)* | 169.4 (11.5–327.4)* | NS |
| A/H3N2 | |||||
| Before | 37.9 (15.5–60.4) | 42.6 (25.2–59.9) | 55.2 (31.8–78.7) | 36.9 (11.9–62.0) | NS |
| After | 120.2 (80.2–160.2)* | 140.7 (82–199.4)*** | 237.8 (169.1–306.5)* | 93.9 (54.1–133.6)** | 0.009 (M vs T) |
| B/B1 | |||||
| Before | 45.5 (30.2–60.7) | 43.2 (29.8–56.5) | 72.1 (53.3–90.9) | 23.9 (12.2–35.6) | 0.017 (T vs C) |
| After | 103.1 (74.9–131.3)* | 105.1 (69.4–140.8)* | 161.8 (123.8–144)* | 68.9 (45.7–92.1)* | 0.044 (M vs T) |
| 0.031 (T vs C) | |||||
| Fold increase | |||||
| A/H1N1 | 12.6 (5.8–19.5) | 14.5 (7.2–21.9) | 12.0 (9.8–17.7) | 11.2 (3.0–19.4) | NS |
| A/H3N2 | 9.6 (5–14.2) | 9.9 (5.2–14.6) | 12.0 (6.6–17.3) | 5.3 (2.7–8.0) | NS |
| B/B1 | 3.5 (2.5–4.4) | 5.4 (2.4–8.3) | 5.0 (3.3–5.7) | 5.8 (3.1–8.4) | NS |
Data are expressed as the mean (95% CIs). Differences between prevaccination and postvaccination GMTs were assessed using the paired-sample t test. Comparisons between the four treatment groups were performed by post hoc ANOVA using Tukey's HSD test.
*p<0.0001, **p=0.009 and ***p=0.001 based on comparisons with prevaccination titres.
ANOVA, analysis of variance; C, RA control group; GMT, geometric mean titre; HI, haemagglutination inhibition; HSD, honestly significant difference; M, MTX group; MTX, methotrexate; NS, not significant; RA, rheumatoid arthritis; T, TCZ group; TCZ, tocilizumab.