Table 2.
Distribution of baseline characteristics by menopausal hormone therapy use among peri- and post-menopausal women and by oral contraceptive use among all women in the EPIC cohort*
| Characteristic | Menopausal hormone therapy use (HRT) | Oral contraceptive use (OC) | ||||
|---|---|---|---|---|---|---|
|
| ||||||
| Never (n = 101,573) |
Former (n = 17,362) |
Current (n = 39,711) |
Never (n=112,303) |
Former (n=136,862) |
Current (n=16.223) |
|
| Mean age at recruitment (SD), yrs | 57.0 (7.4) | 57.4 (5.8) | 54.4 (5.3) | 54.8 (9.9) | 48.7 (8.8) | 37.2 (9.2) |
| Smoking status, % | ||||||
| Never | 59.0 | 50.7 | 47.7 | 62.8 | 46.7 | 54.1 |
| Former | 21.7 | 26.4 | 28.0 | 18.8 | 27.8 | 23.1 |
| Current | 19.3 | 22.9 | 24.3 | 18.5 | 25.5 | 22.8 |
| Mean body mass index (SD), kg/m2 | 26.5 (4.8) | 26.3 (4.4) | 25.1 (3.9) | 26.5 (4.8) | 24.9 (4.3) | 23.6 (3.8) |
| Ever use of OCs, % | ||||||
| Yes | 41.0 | 53.2 | 64.6 | |||
| No | 58.2 | 46.1 | 34.6 | |||
| Unknown | 0.8 | 0.7 | 0.8 | |||
| Education (%) | ||||||
| None/Primary | 48.8 | 43.0 | 33.0 | 52.7 | 27.4 | 12.7 |
| Technical/professional | 24.2 | 30.5 | 36.0 | 20.9 | 32.0 | 32.5 |
| Secondary | 14.4 | 13.1 | 14.7 | 13.6 | 18.0 | 23.0 |
| University | 12.6 | 13.4 | 16.3 | 12.8 | 22.6 | 31.8 |
| Mean age at menarche (SD) | 13.3 (1.6) | 13.2 (1.6) | 13.3 (1.6) | 13.2 (1.6) | 13.1 (1.5) | 12.9 (1.5) |
| Nulliparous (%) | 9.3 | 9.7 | 7.9 | 13.1 | 10.4 | 37.4 |
| Mean age at first pregnancy (SD)† | 25.0 (4.4) | 24.5 (4.3) | 24.2 (4.2) | 25.0 (4.4) | 24.7 (4.5) | 24.8 (4.5) |
| Mean age at menopause (SD) ‡ | 48.7 (4.8) | 48.2 (5.3) | 47.5 (5.5) | 48.5 (5.1) | 48.4 (4.8) | 44.8 (7.7) |
| Hysterectomy (%) | 12.7 | 19.2 | 23.1 | 13.7 | 11.8 | 0 |
*
χ2 and one-way analysis of variance or Kruskal-Wallis test; all tests were p<0.001.
Abbreviations: SD, standard deviation; OCs, oral contraceptives
†
Among parous women
‡
Among natural postmenopausal women