Table 5.
Alcohol consumption in earlier and later adult life and breast cancer risk
| All Invasive Breast Cancers | ||||||||
|---|---|---|---|---|---|---|---|---|
| 18-40 years | Cumulative >40 years | |||||||
| Alcohol (gm/day) | Cases/person-years | Incidence rate per 100,000 person-years | RR (95%CI) Model 1* | RR (95%CI) Model 2** | Cases/person-years | Incidence rate per 100,000 person-years | RR (95%CI) Model 1* | RR (95%CI) Model 2** |
| 0 | 816/235246 | 347 | 1.0 (ref) | 1.0 (ref) | 976/283346 | 344 | 1.0 (ref) | 1.0 (ref) |
| 0.1-4.9 | 3028/828044 | 366 | 1.06 (0.97-1.14) | 1.02 (0.93-1.12) | 2162/606120 | 357 | 1.03 (0.95-1.11) | 1.02 (0.93-1.10) |
| 5-9.9 | 748/189544 | 395 | 1.13 (1.02-1.26) | 1.05 (0.93-1.18) | 703/185850 | 378 | 1.09 (0.99-1.20) | 1.07 (0.96-1.19) |
| 10-19.9 | 322/74250 | 434 | 1.25 (1.09-1.43) | 1.15 (0.99-1.33) | 691/99266 | 426 | 1.20 (1.09-1.33) | 1.17 (1.04-1.31) |
| ≥ 20 | 42/97968 | 429 | 1.33 (0.97-1.82) | 1.21 (0.88-1.67) | 424 | 429 | 1.23 (1.09-1.39) | 1.18 (1.03-1.34) |
| RR per 10 gm increase | 4956/1336212 | 371 | 1.16 (1.08-1.25) | 1.10 (1.02-1.20) | 4956/1336212 | 371 | 1.08 (1.05-1.12) | 1.07 (1.03-1.11) |
| P for trend | <0.001 | 0.02 | <0.001 | <0.001 | ||||
*
Model lanalyses begin with 1988 follow-up period when drinking in earlier adult life was first assessed. For cumulative alcohol intake after age 40, cumulative intake was calculated from baseline (1980) going forward for nurses 40 or older at baseline and from the time the nurse turned 40 for those younger than 40 at baseline. All relative risks were controlled for same variables as Table 2.
**
Model 2 is the same as Model 1, but both alcohol intake at ages 18 – 40 and cumulative alcohol intake are included in the same model