Table 4.
Association between dietary intake of folate, vitamin B6, B12, methionine and breast cancer risk among all EA women and stratified by menopausal status in the WCHS
| All women | Premenopausal | Postmenopausal | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ca (n) | Co (n) | OR1 | 95% CI2 | Ca (n) | Co (n) | OR1 | 95% CI2 | Ca (n) | Co (n) | OR1 | 95% CI2 | |
| Total dietary folate DFE, mcg/day | ||||||||||||
| Q1 (≤334.8) | 167 | 132 | 1.00 | 85 | 74 | 1.00 | 82 | 58 | 1.00 | |||
| Q2 (334.9–468.8) | 181 | 185 | 0.85 | 0.60–1.19 | 79 | 102 | 0.68 | 0.42–1.12 | 102 | 83 | 0.90 | 0.54–1.51 |
| Q3 (468.9–636.4) | 171 | 165 | 0.99 | 0.68–1.44 | 96 | 89 | 1.07 | 0.63–1.81 | 75 | 76 | 0.83 | 0.47–1.47 |
| Q4 (>636.4) | 209 | 197 | 1.11 | 0.72–1.70 | 119 | 107 | 1.11 | 0.60–2.06 | 90 | 90 | 0.96 | 0.51–1.82 |
| p for linear trend | 0.35 | 0.31 | 0.94 | |||||||||
| Natural folate from food, mcg/day | ||||||||||||
| Q1 (≤159.6) | 151 | 129 | 1.00 | 78 | 76 | 1.00 | 73 | 53 | 1.00 | |||
| Q2 (159.7–230.6) | 223 | 172 | 1.24 | 0.88–1.74 | 110 | 102 | 1.13 | 0.70–1.84 | 113 | 70 | 1.36 | 0.80–2.32 |
| Q3 (230.7–315.1) | 181 | 185 | 0.95 | 0.65–1.40 | 92 | 99 | 0.96 | 0.57–1.63 | 89 | 86 | 1.01 | 0.56–1.82 |
| Q4 (>315.1) | 173 | 193 | 0.89 | 0.58–1.37 | 99 | 95 | 1.03 | 0.56–1.88 | 74 | 98 | 0.65 | 0.33–1.26 |
| p for linear trend | 0.24 | 0.89 | 0.05 | |||||||||
| Synthetic folate from fortified food, mcg/day | ||||||||||||
| Q1 (≤78.1) | 161 | 150 | 1.00 | 75 | 73 | 1.00 | 86 | 77 | 1.00 | |||
| Q2 (78.2–129.8) | 182 | 170 | 1.20 | 0.86–1.68 | 93 | 89 | 1.17 | 0.72–1.89 | 89 | 81 | 1.14 | 0.70–1.85 |
| Q3 (129.9–188.6) | 157 | 175 | 0.97 | 0.68–1.37 | 81 | 103 | 0.80 | 0.48–1.33 | 76 | 72 | 1.12 | 0.66–1.88 |
| Q4 (>188.6) | 228 | 184 | 1.53 | 1.06–2.21 | 130 | 107 | 1.43 | 0.83–2.46 | 98 | 77 | 1.48 | 0.87–2.52 |
| p for linear trend | 0.03 | 0.17 | 0.17 | |||||||||
| Vitamin B6, mg/day | ||||||||||||
| Q1 (≤1.17) | 151 | 124 | 1.00 | 79 | 72 | 72 | 52 | 1.00 | ||||
| Q2 (1.18–1.63) | 194 | 182 | 0.98 | 0.69–1.39 | 87 | 110 | 0.71 | 0.43–1.17 | 107 | 72 | 1.16 | 0.68–1.99 |
| Q3 (1.64–2.13) | 162 | 174 | 0.94 | 0.63–1.38 | 97 | 95 | 1.11 | 0.65–1.90 | 65 | 79 | 0.69 | 0.38–1.26 |
| Q4 (>2.13) | 221 | 199 | 1.14 | 0.73–1.77 | 116 | 95 | 1.31 | 0.70–2.46 | 105 | 104 | 0.84 | 0.43–1.64 |
| p for linear trend | 0.48 | 0.12 | 0.37 | |||||||||
| Vitamin B12, mcg/day | ||||||||||||
| Q1 (≤3.13) | 175 | 151 | 1.00 | 92 | 86 | 83 | 65 | 1.00 | ||||
| Q2 (3.14–4.93) | 192 | 178 | 1.04 | 0.75–1.44 | 95 | 98 | 0.96 | 0.61–1.51 | 97 | 80 | 1.15 | 0.70–1.91 |
| Q3 (4.94–7.08) | 180 | 194 | 0.91 | 0.65–1.29 | 99 | 111 | 0.86 | 0.53–1.38 | 81 | 83 | 1.00 | 0.58–1.71 |
| Q4 (>7.08) | 181 | 156 | 1.04 | 0.71–1.54 | 93 | 77 | 1.01 | 0.58–1.76 | 88 | 79 | 1.09 | 0.60–1.96 |
| p for linear trend | 0.91 | 0.97 | 0.98 | |||||||||
| Methionine, g/day | ||||||||||||
| Q1 (≤1.03) | 166 | 135 | 1.00 | 77 | 77 | 89 | 58 | 1.00 | ||||
| Q2 (1.04–1.47) | 205 | 176 | 1.08 | 0.77–1.53 | 94 | 98 | 1.13 | 0.69–1.84 | 111 | 78 | 1.14 | 0.67–1.93 |
| Q3 (1.48–1.96) | 179 | 205 | 0.83 | 0.56–1.22 | 105 | 113 | 1.27 | 0.74–2.18 | 74 | 92 | 0.58 | 0.32–1.06 |
| Q4 (>1.96) | 178 | 163 | 1.13 | 0.68–1.87 | 103 | 84 | 1.93 | 0.95–3.91 | 75 | 79 | 0.67 | 0.31–1.44 |
| p for linear trend | 0.90 | 0.06 | 0.11 | |||||||||
Abbreviations: Ca, Cases; Co, Controls; OR, Odds ratio; 95% CI, 95% confidence interval.
1, 2
Models are adjusted for age, ethnicity, country of origin, education, BMI, age at menarche, menopausal status (when not stratified by this variable), age at menopause (only for postmenopausal women), parity, age at first birth, breastfeeding status, family history of breast cancer, OC use, history of benign breast disease, HRT use, smoking status, alcohol consumption, and total energy intake.