Unadjusted incidence of gastric and colon cancer in women who underwent endoscopy procedure within 1 year of testing for iron deficiency*
| Iron deficient | Non-iron deficient | P value | |||||
| Sample size (n) | Cancer† (n) | Incidence/1000 patients (95% CI) | Sample size (n) | Cancer† (n) | Incidence/1000 patients (95% CI) | ||
| Anaemic women (n=653) | |||||||
| Gastric cancer | |||||||
| Age 20–49 years | 527 | 1 | 1.90 (0.34 to 10.67) | 126 | 1 | 7.94 (1.40 to 43.59) | 0.35 |
| 20–29 | 11 | 0 | – | 4 | 0 | – | – |
| 30–39 | 82 | 1 | 12.20 (2.16 to 65.89) | 36 | 0 | – | >0.99 |
| 40–49 | 434 | 0 | – | 86 | 1 | 11.63 (2.06 to 62.96) | 0.17 |
| Colon cancer | |||||||
| Age 20–49 years | 527 | 8 | 15.18 (7.71 to 29.67) | 126 | 2 | 15.87 (4.36 to 56.03) | >0.99 |
| 20–29 | 11 | 0 | – | 4 | 0 | – | – |
| 30–39 | 82 | 4 | 48.78 (19.13 to 118.80) | 36 | 1 | 27.78 (4.92 to 141.70) | >0.99 |
| 40–49 | 434 | 4 | 9.22 (3.59 to 23.46) | 86 | 1 | 11.63 (2.06 to 62.96) | >0.99 |
| Non†anaemic women (n=939) | |||||||
| Gastric cancer | |||||||
| Age 20–49 years | 388 | 0 | – | 551 | 0 | – | – |
| 20–29 | 33 | 0 | – | 47 | 0 | – | – |
| 30–39 | 75 | 0 | – | 132 | 0 | – | – |
| 40–49 | 280 | 0 | – | 372 | 0 | – | – |
| Colon cancer | |||||||
| Age 20–49 years | 388 | 7 | 18.04 (8.77 to 36.77) | 551 | 3 | 5.44 (1.85 to 15.88) | 0.10 |
| 20–29 | 33 | 0 | – | 47 | 0 | – | – |
| 30–39 | 75 | 1 | 13.33 (2.36 to 71.73) | 132 | 1 | 7.58 (1.34 to 41.66) | >0.99 |
| 40–49 | 280 | 6 | 21.43 (9.86 to 45.95) | 372 | 2 | 5.38 (1.48 to 19.39) | 0.08 |
–, not applicable.
*No comparisons were significant due to small event size.
†Within 5 years of the iron deficiency test date.