Table 2. Hazard ratio of all-cause and breast cancer-specific death associated with alcohol drinking among overall women.
Factor | Patients | Person-years | All-cause death | Breast cancer-specific death | ||||
---|---|---|---|---|---|---|---|---|
Deaths | Multivariate-adjusted 1a | Multivariate-adjusted 2b | Deaths | Multivariate-adjusted 1a | Multivariate-adjusted 2b | |||
HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | |||||
History of alcohol drinking | ||||||||
Never | 1015 | 7922.7 | 206 | 1 (Reference) | 1 (Reference) | 150 | 1 (Reference) | 1 (Reference) |
Ever (Current/past) | 405 | 3258.2 | 55 | 0.78 (0.57–1.06) | 0.75 (0.54–1.05) | 43 | 0.67 (0.47–0.96) | 0.68 (0.46–0.99) |
Past | 48 | 348.6 | 8 | 0.80 (0.39–1.64) | 0.70 (0.32–1.52) | 6 | 0.57 (0.24–1.32) | 0.53 (0.21–1.33) |
Current | 357 | 2909.6 | 47 | 0.77 (0.55–1.08) | 0.76 (0.53–1.08) | 37 | 0.70 (0.48–1.01) | 0.70 (0.47–1.04) |
Age at start of drinking (years) | ||||||||
≥ 21 | 173 | 1418.3 | 25 | 0.74 (0.49–1.13) | 0.73 (0.47–1.13) | 20 | 0.72 (0.45–1.16) | 0.74 (0.45–1.21) |
≤ 20 | 199 | 1575.6 | 27 | 0.89 (0.58–1.37) | 0.87 (0.55–1.36) | 20 | 0.65 (0.40–1.07) | 0.65 (0.39–1.10) |
p for trend | 0.33 | 0.31 | 0.04 | 0.07 | ||||
(Finer categorization) | ||||||||
> 25 | 111 | 901.1 | 15 | 0.79 (0.47–1.35) | 0.79 (0.45–1.36) | 12 | 0.91 (0.50–1.64) | 0.87 (0.47–1.63) |
≥21 - ≤ 25 | 62 | 517.2 | 10 | 0.67 (0.35–1.28) | 0.66 (0.34–1.28) | 8 | 0.55 (0.27–1.14) | 0.59 (0.28–1.25) |
≤ 20 | 199 | 1575.6 | 27 | 0.89 (0.58–1.37) | 0.86 (0.55–1.36) | 20 | 0.65 (0.39–1.06) | 0.65 (0.39–1.10) |
p for trend | 0.31 | 0.29 | 0.03 | 0.05 | ||||
Frequency of drinking (times) | ||||||||
Occasional or 1–2 per week | 187 | 1524.5 | 22 | 0.67 (0.42–1.05) | 0.70 (0.44–1.13) | 16 | 0.52 (0.31–0.89) | 0.57 (0.33–0.99) |
3–7 per week | 198 | 1586.7 | 28 | 0.83 (0.55–1.24) | 0.75 (0.48–1.17) | 23 | 0.76 (0.48–1.19) | 0.72 (0.43–1.18) |
p for trend | 0.17 | 0.12 | 0.07 | 0.08 | ||||
(Finer categorization) | ||||||||
Occasional | 96 | 800.0 | 15 | 0.77 (0.45–1.32) | 0.81 (0.46–1.41) | 10 | 0.53 (0.27–1.03) | 0.58 (0.29–1.14) |
1–2 per week | 91 | 724.5 | 7 | 0.52 (0.24–1.12) | 0.55 (0.25–1.21) | 6 | 0.51 (0.22–1.16) | 0.57 (0.24–1.33) |
3–4 per week | 94 | 775.9 | 11 | 0.58 (0.31–1.08) | 0.52 (0.27–1.00) | 11 | 0.62 (0.33–1.16) | 0.58 (0.29–1.15) |
5–7 per week | 104 | 810.8 | 17 | 1.13 (0.68–1.88) | 1.04 (0.60–1.80) | 12 | 0.95 (0.52–1.72) | 0.90 (0.47–1.71) |
p for trend | 0.28 | 0.20 | 0.13 | 0.15 | ||||
Amount of alcohol consumed per day (g) | ||||||||
< 5.0 | 171 | 1395.9 | 20 | 0.65 (0.40–1.04) | 0.68 (0.42–1.11) | 15 | 0.52 (0.30–0.89) | 0.57 (0.32–1.00) |
≥ 5.0 | 204 | 1649.4 | 28 | 0.81 (0.54–1.22) | 0.72 (0.46–1.12) | 23 | 0.73 (0.47–1.15) | 0.68 (0.41–1.12) |
p for trend | 0.14 | 0.08 | 0.05 | 0.06 | ||||
(Finer categorization) | ||||||||
< 5.0 | 171 | 1395.9 | 20 | 0.65 (0.40–1.04) | 0.68 (0.42–1.11) | 15 | 0.52 (0.30–0.89) | 0.57 (0.32–1.00) |
≥5.0 - < 15.0 | 115 | 937.8 | 15 | 0.69 (0.40–1.18) | 0.61 (0.35–1.08) | 14 | 0.69 (0.39–1.21) | 0.66 (0.35–1.22) |
≥ 15 | 89 | 711.6 | 13 | 1.01 (0.57–1.79) | 0.90 (0.49–1.66) | 9 | 0.82 (0.41–1.62) | 0.71 (0.34–1.48) |
p for trend | 0.26 | 0.15 | 0.09 | 0.08 |
Abbreviations: HR, hazard ratio; CI, confidence interval.
aAdjusted by age, year of diagnosis, stage (0-I, II, III, IV, missing), hormone receptor (ER+ or PR+, ER-/PR-, missing), and menopausal status (premenopausal, postmenopausal, missing).
bAdjusted by age, year of diagnosis, stage (0-I, II, III, IV, missing), hormone receptor (ER+ or PR+, ER-/PR-, missing), referral status (from screening, other), radiation therapy (no, yes), chemotherapy (no, yes), endocrine therapy (no, yes), family history of breast cancer in parents or siblings (no, yes), smoking (ever, never, missing), BMI (<21.1, 21.1-<23.3, 23.3-<26.0, 26.0-, missing), physical activity (almost no, more than one hour per week, missing), comorbidities (no, yes), occupation (housewife, other, missing), age at menarche (≤12, 13, 14, 15<, missing), parity history (nulliparous, parous, missing), menopausal status (premenopausal, postmenopausal, missing), and intake of folate (continuous) and energy (continuous).