Table 3. Risk of breast cancer associated with ethnic subgroup, before and after adjustment for reproductive and socio-economic factors.
| Ethnic subgroup (cases/controls) | Gujarati Hindu (80/186) |
Punjabi Hindu (18/54) |
Punjabi Sikh (58/105) |
Pakistani/Indian Muslim (76/101) |
||||
|---|---|---|---|---|---|---|---|---|
| Controlled for age and GP (through matching) and: | ORa | ORa | 95% CIb | ORa | 95% CIb | ORa | 95% CIb | P-valuec |
| — | 1 | 0.65 | 0.34, 1.28 | 1.26 | 0.74, 2.12 | 1.88 | 1.19, 2.98 | 0.008 |
| Age at menarche | 1 | 0.61 | 0.21, 1.19 | 1.29 | 0.76, 2.18 | 1.91 | 1.20, 3.04 | 0.005 |
| Age at first birth | 1 | 0.66 | 0.33, 1.30 | 1.28 | 0.75, 2.17 | 1.79 | 1.12, 2.86 | 0.017 |
| Parity | 1 | 0.68 | 0.35, 1.33 | 1.28 | 0.75, 2.16 | 2.04 | 1.28, 3.26 | 0.005 |
| Time since menopause | 1 | 0.70 | 0.36, 1.38 | 1.34 | 0.79, 2.28 | 1.96 | 1.23, 3.12 | 0.008 |
| Family history of breast cancer | 1 | 0.65 | 0.34, 1.28 | 1.24 | 0.73, 2.09 | 1.90 | 1.20, 3.01 | 0.008 |
| Breast fedd | 1 | 0.67 | 0.34, 1.31 | 1.21 | 0.71, 2.05 | 1.91 | 1.20, 3.04 | 0.009 |
| Years of formal educatione | 1 | 0.64 | 0.32, 1.26 | 1.40 | 0.82, 2.38 | 2.21 | 1.37, 3.56 | 0.001 |
| Years since migration to UK | 1 | 0.65 | 0.33, 1.27 | 1.24 | 0.76, 2.10 | 1.89 | 1.19, 2.99 | 0.008 |
| All of the above | 1 | 0.74 | 0.36, 1.52 | 1.49 | 0.85, 2.62 | 2.32 | 1.38, 3.88 | 0.003 |
a
OR=odds ratio, estimated from a conditional logistic regression model.
b
CI=confidence interval.
c
P-value for heterogeneity in odds of breast cancer by ethnic subgroup.
d
Breast feeding: 0–4.4, 4.5–11, 12–23, 24–47, ⩾48 months, never.
e
Years of formal education: 0, 1–7, 8–13, ⩾14 years.