| Means comparison for IgG at 6 and 9 months (n = 102) | Means, statistic and p-value |
| IgG 6 months | 2368.52 (DE 2933.12) |
| IgG 9 months | 1699.48 (DE 2443.77) |
|
| Wilcoxon Z = −7.770; p = 0.000 |
| Groups in which the decrease in IgG levels are significant | Means, statistic and p-value |
| >50 years |
|
| IgG 6 months | 1971.63 (SD 2021.07) |
| IgG 9 months | 1241.99 (SD 1500.62) |
|
| Wilcoxon Z = −4.869; p = 0.000 |
| Men |
|
| IgG 6 months | 3345.23 (SD 3543.07) |
| IgG 9 months | 2653.07 (SD 2978.28) |
|
| Wilcoxon Z = −3.70; p = 0.000 |
| Women |
|
| IgG 6 months | 1998.96 (SD 2599.17) |
| IgG 9 months | 1338.67 (SD 2121.59) |
|
| Wilcoxon Z = −6.89; p = 0.000 |
| Active smokers |
|
| IgG 6 months | 1151.94 (SD 1204.47) |
| IgG 9 months | 673.18 (SD 626.10) |
| Non-smokers |
|
| IgG 6 months | 2737.76 (SD 3507.67) |
| IgG 9 months | 2056.28 (SD 2961.99) |