Crude and adjusted HRs for the association between the use of PPIs and gastric cancer compared with the use of H2RAs
| Events | Person-years | Incidence rate (95% CI) * | Crude HR | Calendar-year weighted HR (95% CI) | Marginal HR (95% CI) † | |
| H2RAs (n=198 306) | 244 | 947 418 | 25.8 (22.6 to 29.2) | 1.00 | 1.00 (reference) | 1.00 (reference) |
| PPIs (n=973 281) | 1166 | 4 887 771 | 23.9 (22.5 to 25.3) | 0.92 | 1.34 (1.14 to 1.57) | 1.45 (1.06 to 1.98) |
| Cumulative duration of proton pump inhibitors | ||||||
| <2 years | 861 | 3 830 738 | 22.5 (21.0 to 24.0) | 0.82 | 1.21 (1.03 to 1.42) | 1.33 (0.96 to 1.83) |
| 2–3.9 years | 140 | 518 719 | 27.0 (22.7 to 31.8) | 1.16 | 1.65 (1.31 to 2.07) | 1.88 (1.33 to 2.65) |
| ≥4 years | 165 | 538 314 | 30.7 (26.2 to 35.7) | 1.47 | 2.09 (1.67 to 2.62) | 2.40 (1.68 to 3.45) |
| Cumulative omeprazole dose equivalents | ||||||
| <14 600 mg | 886 | 3 933 697 | 22.5 (21.1 to 24.1) | 0.83 | 1.22 (1.04 to 1.43) | 1.33 (0.97 to 1.83) |
| 14 600–28 199 mg | 147 | 502 892 | 29.2 (24.7 to 34.4) | 1.27 | 1.81 (1.45 to 2.26) | 2.05 (1.46 to 2.89) |
| ≥29 200 mg | 143 | 451 182 | 29.5 (24.7 to 34.9) | 1.39 | 2.03 (1.60 to 2.58) | 2.34 (1.62 to 3.37) |
| Time since proton pump inhibitor initiation | ||||||
| <2 years | 293 | 892 171 | 32.8 (29.2 to 36.8) | 0.94 | 1.63 (1.17 to 2.29) | 1.25 (0.69 to 2.28) |
| 2–3.9 years | 334 | 1 404 884 | 23.8 (21.3 to 26.5) | 0.81 | 1.24 (0.92 to 1.67) | 1.32 (0.79 to 2.19) |
| ≥4 years | 539 | 2 590 716 | 20.8 (19.1 to 22.6) | 0.98 | 1.26 (1.01 to 1.56) | 1.82 (1.09 to 3.02) |
*Crude incidence rate per 100 000 person-years.
†Weighted using standardised mortality ratio weights.
H2RA, histamine-2 receptor antagonist; PPI, proton pump inhibitor.