Table 3.
Association of IgG2 and IgG4 with malaria incidence.
| Antigen | Antibody | Crude IRR (95%CI) | P-value | Age-adjusted IRR | P-value | |
| MSP3 | ||||||
| IgG2* | (coded as log(2)) | 0.74 (0.57, 0.98) | 0.04 | 0.85 (0.63, 1.15) | 0.29 | |
| IgG4 | < detection limit | 1 | 0.01 | 1 | 0.20 | |
| < median | 0.45 (0.21, 0.95) | 0.56 (0.26, 1.19) | ||||
| ≥ median | 0.47 (0.28, 0.79) | 0.68 (0.40, 1.15) | ||||
| MSP119 | ||||||
| IgG2* | (coded as log(2)) | 0.62 (0.45, 0.86) | < 0.01 | 0.836 (0.606, 1.157) | 0.275 | |
| IgG4* | (coded as log(2)) | 1.07 (0.95, 1.21) | 0.25 | 0.838 (0.608, 1.159) | 0.278 | |
| GLURP | ||||||
| IgG2* | (coded as log(2)) | 0.65 (0.49, 0.86) | < 0.01 | 0.79 (0.58, 1.08) | 0.13 | |
| IgG4* | (coded as log(2)) | 0.94 (0.81, 1.08) | 0.37 | 1.01 (0.87, 1.16) | 0.94 | |
| AMA1 | ||||||
| IgG2 | < detection limit | 1 | 0.18 | 1 | 0.54 | |
| < median | 1.80 (0.86, 3.78) | |||||
| ≥ median | 1.78 (0.90, 3.51) | |||||
| IgG4 | < detection limit | 1 | 0.19 | 1 | 0.54 | |
| < median | 0.96 (0.47, 1.93) | |||||
| ≥ median | 0.62 (0.36, 1.07) | |||||
For IgG 2 to AMA1 and for IgG4 to AMA1 and MSP3, antibody level was categorized.
*For IgG2 to MSP3, MSP119 and GLURP, the association is expressed as the incidence rate ratio (IRR) corresponding to a doubling of baseline antibody level.