Table 2.
Odds ratios and 95% confidence intervals for the associations of diabetes with incident invasive breast cancer, South Texas Women’s Health Project, 2003–2008
| Characteristic | Cases (n=190) | High-risk controls (n=511) | ORa | (95% CI) | Low-risk controls (n=468) | ORa | (95% CI) | |||
|---|---|---|---|---|---|---|---|---|---|---|
| N | % | N | % | n | % | |||||
| History of diabetes | ||||||||||
| No | 125 | 65.8 | 354 | 69.3 | 1.00 | (referent) | 306 | 65.5 | (referent) | |
| Yes | 65 | 34.2 | 157 | 30.7 | 1.02 | (0.71–1.48) | 161 | 34.5 | 0.87 | (0.58–1.30) |
| Missing | 0 | 1 | ||||||||
| Type of diabetes | ||||||||||
| Gestational | 3 | 1.7 | 19 | 3.9 | 0.21 | (0.03–1.64) | 8 | 1.8 | 0.26 | (0.03–2.31) |
| Type 2 | 47 | 26.9 | 112 | 23.1 | 1.00 | (0.66–1.51) | 129 | 29.1 | 0.77 | (0.49–1.23) |
| Missing | 15 | 26 | 24 | |||||||
| Age at diabetes onset (years)b | ||||||||||
| <35 | 3 | 1.7 | 12 | 2.6 | 0.79 | (0.21–2.96) | 11 | 2.6 | 0.66 | (0.17–2.61) |
| ≥35 | 44 | 25.6 | 99 | 21.3 | 0.96 | (0.63–1.47) | 115 | 26.6 | 0.80 | (0.51–1.26) |
| Missing | 0 | 1 | 3 | |||||||
| Diabetes treatmentb | ||||||||||
| Insulin | 22 | 12.8 | 25 | 5.4 | 2.23 | (1.18–4.19) | 37 | 8.5 | 1.24 | (0.66–2.31) |
| Oral med. | 21 | 12.2 | 71 | 15.2 | 0.72 | (0.42–1.23) | 64 | 14.7 | 0.77 | (0.43–1.38) |
| No insulin or oral med. | 4 | 2.3 | 16 | 3.4 | 0.55 | (0.18–1.70) | 28 | 6.4 | 0.31 | (0.10–0.96) |
| Family history of diabetes | ||||||||||
| No | 59 | 31.6 | 160 | 31.6 | 1.00 | (referent) | 154 | 33.3 | 1.00 | (referent) |
| Yes | 128 | 68.4 | 346 | 63.4 | 1.02 | (0.71–1.49) | 309 | 66.7 | 1.16 | (0.77–1.74) |
| Missing | 3 | 5 | 5 | |||||||
a
Odds ratio (OR) and 95% confidence interval (95% CI) adjusted for menopausal status and mammography screening.
b
Among women with type 2 diabetes.