Strata
|
Total number of cases in strata
|
HR for ever smoking relative to never smoking within strata of alcohol consumptiona
|
95% CI
|
P value
|
---|
Alcoholb
|
Non-drinker
|
110
|
0.97
|
0.61–1.52
|
0.89
|
Ever drinker
|
1705
|
1.18
|
1.07–1.30
|
0.0010
|
| |
Interaction P
c = 0.41
|
Alcoholb
|
Non-drinker
|
110
|
0.97
|
0.61–1.52
|
0.89
|
< 20 g/day
|
706
|
1.17
|
1.00–1.36
|
0.049
|
20 to < 40 g/day
|
356
|
1.17
|
0.95–1.44
|
0.13
|
40 to < 60 g/day
|
87
|
1.12
|
0.73–1.72
|
0.61
|
≥ 60 g/day
|
27
|
1.92
|
0.78–4.76
|
0.16
|
Current, amount unknown
|
180
|
1.47
|
1.09–1.98
|
0.011
|
Former drinker
|
295
|
0.98
|
0.78–1.25
|
0.89
|
Drinker, details missing
|
54
|
0.73
|
0.38–1.42
|
0.35
|
| |
Interaction P
c = 0.33
|
-
aAdjusted for attained age (Cox regression time scale); time since recruitment to cohort (0, 1–2, 3+ years); birth cohort (1908–1939, 1940–1949, 1950–1959, 1960–1969, 1970–1996); benign breast disease (yes/no); family history of breast cancer in first-degree relatives (yes/no); socio-economic score (Acorn score as trend, missing); age at menarche (trend, missing); age at first pregnancy (trend, missing); parity (trend, missing); duration of breastfeeding (trend, missing); current oral contraceptive use before menopause (yes/no); physical activity [log(metabolic equivalent) trend, missing]; pre-menopausal body mass index at age 20 years (trend, missing); post-menopausal body mass index (trend, missing); menopausal hormone therapy use (never used, ex-user, current oestrogen-only user, current oestrogen plus progestogen user, current user of other types, missing); menopausal status (pre- or post-menopausal) and age at menopause (trend, missing)
-
bTime updated through follow-up period
-
cInteraction across all categories, including missing groups