Table 1.
Characteristics of post-menopausal women in the Million Women Study at recruitment and follow-up according to BMI and strenuous physical activity a.
| BMI (kg/m2) |
Strenuous exercise |
All women | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| < 20.0 | 20.0–22.4 | 22.5–24.9 | 25.0–27.4 | 27.5–29.9 | 30 + | Rarely/never (inactive) | At most once per week | More than once per week | ||
| Characteristics at baseline | n = 41 818 | n = 180 331 | n = 313 534 | n = 251 549 | n = 162 477 | n = 205 595 | n = 553 040 | n = 356 539 | n = 245 725 | n = 1 155 304 |
| Mean age at recruitment, years (SD) | 55.8 (4.9) | 55.6 (4.8) | 55.9 (4.8) | 56.3 (4.8) | 56.3 (4.8) | 56.1 (4.7) | 56.4 (4.9) | 55.7 (4.7) | 55.8 (4.7) | 56.0 (4.8) |
| Mean height, cm (SD) | 164.0 (7.1) | 163.4 (6.4) | 162.6 (6.4) | 161.7 (6.5) | 161.4 (6.6) | 160.5 (7.0) | 161.6 (6.7) | 162.4 (6.5) | 162.5 (6.6) | 162.0 (6.7) |
| Mean weight, kg (SD) | 50.9 (4.9) | 57.2 (4.8) | 62.9 (5.2) | 68.5 (5.7) | 74.6 (6.4) | 87.6 (11.7) | 70.1 (13.5) | 68.3 (11.8) | 66.8 (11.3) | 68.8 (12.6) |
| Mean BMI, kg/m2 (SD) | 18.9 (0.9) | 21.4 (0.7) | 23.7 (0.7) | 26.1 (0.7) | 28.6 (0.7) | 34.0 (3.8) | 26.9 (5.0) | 25.9 (4.3) | 25.3 (4.1) | 26.2 (4.7) |
| Mean alcohol, grammes/day (SD) | 6.7 (8.2) | 7.3 (8.0) | 7.0 (7.8) | 6.4 (7.5) | 5.8 (7.3) | 4.7 (6.8) | 5.6 (7.4) | 6.7 (7.4) | 7.4 (8.2) | 6.3 (7.6) |
| Mean number of children (SD) | 1.9 (1.4) | 2.0 (1.2) | 2.1 (1.2) | 2.2 (1.3) | 2.3 (1.3) | 2.4 (1.4) | 2.2 (1.3) | 2.1 (1.2) | 2.1 (1.3) | 2.2 (1.3) |
| Current smoker (%) | 31.8 | 22.9 | 20.0 | 19.0 | 18.2 | 16.0 | 24.4 | 15.4 | 15.6 | 19.7 |
| Socioeconomic status: lowest fifth (%) | 19.1 | 15.3 | 15.9 | 18.3 | 20.9 | 25.6 | 23.9 | 14.1 | 14.5 | 18.9 |
| Never users of hormone therapy (%) | 50.4 | 48.4 | 48.2 | 48.7 | 49.6 | 53.4 | 50.4 | 48.7 | 48.5 | 49.5 |
| No physical activity (%) | 20.1 | 15.6 | 16.7 | 20.0 | 24.2 | 31.9 | 42.7 | 1.2 | 1.2 | 21.1 |
| No strenuous activity (%) | 47.1 | 40.5 | 42.6 | 47.3 | 52.2 | 59.9 | – | – | – | 47.9 |
| Follow-up for fracture incidence | ||||||||||
| Woman-years of follow-up (in millions) | 0.34 | 1.48 | 2.60 | 2.10 | 1.35 | 1,69 | 4.58 | 2.94 | 2.04 | 9.56 |
| Incident ankle fractures (n) | 109 | 660 | 1620 | 1614 | 1204 | 1600 | 3295 | 2068 | 1444 | 6807 |
| Incident wrist fractures (n) | 442 | 1800 | 2892 | 2079 | 1224 | 1296 | 4654 | 2910 | 2169 | 9733 |
| Incident hip fractures (n) | 497 | 1168 | 1451 | 1032 | 543 | 576 | 3149 | 1292 | 826 | 5267 |
a
Women with missing values were excluded when calculating the means or percentages for that given variable.