Cumulative average coffee and tea consumption and risk of endometrial cancer in the NHS cohort
| Coffee intake, RR (95% CI) | |||||
|---|---|---|---|---|---|
| <1 cup/d | 1 cup/d | 2–3 cups/d | ≥4 cups/d | Ptrend | |
| Person-years | 301,317 | 211,400 | 514,014 | 256,514 | |
| No. of cases | 168 | 140 | 275 | 89 | |
| Age-adjusted | 1.00 | 0.95 (0.76–1.19) | 0.81 (0.67–0.98) | 0.61 (0.47–0.79) | <0.001 |
| Multivariable-adjusteda | 1.00 | 1.04 (0.83–1.31) | 0.93 (0.76–1.14) | 0.75 (0.57–0.97) | 0.02 |
| Multivariable-adjustedb | 1.00 | 0.94 (0.73–1.19) | 0.94 (0.77–1.16) | 0.68 (0.52–0.90) | 0.01 |
| Caffeinated coffee intake, RR (95% CI) | |||||
| <1 cup/d | 1 cup/d | 2–3 cups/d | ≥4 cups/d | Ptrend | |
| Person-years | 423,877 | 240,812 | 434,482 | 184,075 | |
| No. of cases | 255 | 151 | 212 | 54 | |
| Age-adjusted | 1.00 | 0.94 (0.77–1.15) | 0.79 (0.66–0.95) | 0.57 (0.43–0.77) | <0.001 |
| Multivariable-adjusteda | 1.00 | 1.01 (0.82–1.24) | 0.89 (0.74–1.08) | 0.70 (0.51–0.95) | 0.02 |
| Multivariable-adjustedb | 1.00 | 0.97 (0.79–1.21) | 0.92 (0.76–1.12) | 0.66 (0.48–0.91) | 0.02 |
| Decaffeinated coffee intake, RR (95% CI)c | |||||
| <1 cup/mo | 1 cup/mo to <1 cup/d | 1 cup/d | ≥2 cups/d | Ptrend | |
| Person-years | 311,761 | 368,383 | 139,250 | 107,655 | |
| No. of cases | 170 | 245 | 98 | 54 | |
| Age-adjusted | 1.00 | 1.02 (0.84–1.24) | 1.10 (0.85–1.41) | 0.87 (0.64–1.19) | 0.57 |
| Multivariable-adjusteda | 1.00 | 0.92 (0.75–1.14) | 0.96 (0.74–1.25) | 0.78 (0.57–1.08) | 0.23 |
| Multivariable-adjustedb | 1.00 | 0.90 (0.72–1.11) | 1.01 (0.78–1.32) | 0.72 (0.52–1.01) | 0.20 |
| Tea intake, RR (95% CI) | |||||
| <1 cup/mo | 1 cup/mo to <1 cup/d | 1 cup/d | ≥2 cups/d | Ptrend | |
| Person-years | 235,463 | 677,960 | 194,971 | 162,849 | |
| No. of cases | 92 | 385 | 117 | 71 | |
| Age-adjusted | 1.00 | 1.18 (0.94–1.49) | 1.39 (1.06–1.84) | 1.20 (0.88–1.63) | 0.25 |
| Multivariable-adjusteda | 1.00 | 1.10 (0.87–1.40) | 1.24 (0.94–1.65) | 1.06 (0.77–1.46) | 0.70 |
| Multivariable-adjustedb | 1.00 | 0.97 (0.77–1.22) | 1.21 (0.92–1.59) | 0.94 (0.69–1.30) | 0.77 |
↵aAdjusted for age (mo, continuous), BMI (kg/m2, continuous), age at menopause [pre-/unknown menopause, <45 y, 45–46 y, 47–48 (ref), 49–50 y, 51–52 y, and ≥53 y], age at menarche [<12 y, 12 y (ref), and >12 y], parity and age at last birth [nulliparous (ref), parity 1–2 and age at last birth <30 y, parity 1–2 and age at last birth parity ≥30 y, parity 3–4 and age at last birth <30 y, parity 3–4 and age at last birth ≥30 y, parity ≥5 and age at last birth <30 y, and parity ≥5 and age at last birth ≥30 y], duration of oral contraceptive use [never (ref), <3 y, past 3–5 y, and past >5 y], postmenopausal hormone use [premenopausal, postmenopausal never (ref), past PMH, current PMH estrogen only, current PMH estrogen with progesterone], pack-years of smoking [never (ref), >0–10 pack-years, >10–20 pack-years, >20–30 pack-years, >30–40 pack-years, >40 pack-years], alcohol intake [0 (ref), 0.1–4.9g/d, 5.0–14.9g/d, >15.0g/d], and total energy intake [kcal/d, continuous]. Caffeinated coffee and decaffeinated coffee intakes were mutually adjusted in the model. Total coffee intake was adjusted for tea analysis.
↵bExcluded cases that occurred during the first 2-year follow-up period (n = 33 cases) to minimize the possibility that preclinical disease influenced dietary assessment. For decaffeinated coffee analysis, 28 cases were excluded.
↵cFollow-up from 1984.