Baseline characteristics of 70 928 participants from the E3N cohort, by use of menopausal hormone therapy during follow-up
| Characteristic | Use of menopausal hormone therapy* | Type of regimen used | |||
|---|---|---|---|---|---|
| Never n = 18 694 | Ever n = 45 984 | Transdermal estrogen n = 33 584 | Oral estrogen n = 16 736 | Other estrogen n = 6 709 | |
| Length of follow-up, yr, mean (IQR) | 10.5 (5.8–15.9) | 12.1 (7.9–16.2) | 12.6 (10.1–16.4) | 11.9 (10.9–16.3) | 12.0 (7.9–16.3) |
| Age, yr, mean ± SD | 56.4 ± 4.7 | 53.9 ± 4.1 | 53.8 ± 4.0 | 53.2 ± 3.9 | 53.7 ± 4.0 |
| Education level ≥ high school,† no. (%) | 15 986 (85.5) | 41 181 (89.6) | 30 049 (89.5) | 15 119 (90.3) | 6 075 (90.6) |
| BMI,† kg/m2, mean ± SD | 23.3 ± 3.7 | 22.4 ± 2.8 | 22.4 ± 2.8 | 22.2 ± 2.7 | 22.3 ± 2.7 |
| Parity,† mean ± SD | 1.8 ± 1.2 | 1.8 ± 1.1 | 1.8 ± 1.1 | 1.8 ± 1.1 | 1.8 ± 1.1 |
| Hypercholesterolemia, no. (%) | 623 (3.3) | 1 318 (2.9) | 997 (3.0) | 393 (2.3) | 188 (2.8) |
| Diabetes mellitus, no. (%) | 262 (1.4) | 281 (0.6) | 213 (0.6) | 77 (0.5) | 31 (0.5) |
| Hysterectomy, no. (%) | 3 011 (16.1) | 9 404 (20.5) | 7 476 (22.3) | 2 965 (17.7) | 1 225 (18.3) |
| History of gallstone disease not requiring surgery, no. (%) | 341 (1.8) | 749 (1.6) | 563 (1.7) | 257 (1.5) | 94 (1.4) |
| Physical activity,† MET-h/wk, mean ± SD | 44.2 ± 28.5 | 42.0 ± 26.2 | 41.7 ± 25.9 | 41.9 ± 26.4 | 41.6 ± 25.5 |
| Artificial menopause,†‡ no. (%) | 1 741 (9.3) | 3 936 (8.6) | 3 047 (9.1) | 1 323 (7.9) | 505 (7.5) |
| Ever use of oral contraceptives, no. (%) | 9 310 (49.8) | 29 602 (64.4) | 21 371 (63.6) | 11 774 (70.4) | 4 588 (68.4) |
| History of breastfeeding† no. (%) | 10 965 (58.7) | 27 741 (60.3) | 20 195 (60.1) | 10 158 (60.7) | 4 079 (60.8) |
Note: BMI = body mass index, E3N = Étude Épidémiologique de femmes de la Mutuelle Générale de l’Éducation Nationale, IQR = interquartile range, MET-h/wk = metabolic equivalent hours per week, SD = standard deviation.
↵* Data on use of menopausal hormone therapy were missing for 6 250 women, including 211 who reported undergoing cholecystectomy during follow-up.
↵† Data were missing on education level for 2 841 women, on BMI for 76, on parity for 523, on physical activity for 779, on status of artificial menopause for 1 229 and on breastfeeding for 523 women.
↵‡ Artificial menopause due to bilateral oophorectomy or to a specific medical condition (induced by radiation or a drug).