Table 1.
Characteristics of the Sample of 848 Women in the Medical Research Council NSHD With at Least One Bone Measure and Known Type of Menopause
| Maximum Sample pQCT Measures | Total Sample |
Natural Menopause |
Hysterectomy and/or Bilateral Oophorectomy |
P Value | |||
|---|---|---|---|---|---|---|---|
| 848a No | Mean (SD) | 653 No | Mean (SD) | 195 No | Mean (SD) | ||
| Cortical sites: 50% radius | |||||||
| Diaphysis CSA, mm2 | 681 | 112.3 (15.8) | 523 | 112.1 (15.5) | 158 | 113.3 (16.8) | .4 |
| Medullary CSA, mm2 | 681 | 35.2 (12.5) | 523 | 35.6 (12.5) | 158 | 33.8 (12.3) | .1 |
| Polar SSI, mm3 | 682 | 210.6 (43.1) | 524 | 208.6 (42.2) | 158 | 217.2 (45.4) | .03 |
| Trabecular sites: 4% distal radius | |||||||
| Distal CSA, mm2 | 674 | 132.7 (23.9) | 518 | 132.7 (24.5) | 156 | 132.7 (22.0) | >.9 |
| 50% radius | |||||||
| Cortical vBMD, mg/cm3 | 682 | 1148.2 (39.4) | 524 | 1146.8 (40.2) | 158 | 1152.8 (36.3) | .1 |
| Distal radius (4%) | |||||||
| Trabecular vBMD, mg/cm3 | 673 | 171.7 (42.2) | 517 | 169.7 (42.3) | 156 | 178.3 (41.0) | .02 |
| Total vBMD, mg/cm3 | 674 | 329.3 (70.4) | 518 | 325.5 (70.1) | 156 | 342.0 (69.9) | .01 |
| DXA measures | |||||||
| Spine L1-L4 aBMD, g/cm2 | 843 | .944 (.165) | 649 | .934 (.164) | 194 | .976 (.163) | .002 |
| Total hip aBMD, g/cm2 | 839 | .869 (.131) | 645 | .859 (.132) | 194 | .902 (.123) | <.001 |
| Current body size | |||||||
| Height, m | 848 | 1.621 (.058) | 653 | 1.624 (.058) | 195 | 1.613 (.057) | .03 |
| Weight, kg | 848 | 72.4 (14.1) | 653 | 71.5 (14.1) | 195 | 75.4 (14.0) | .001 |
| Reproductive measures | |||||||
| Age at period cessation, y | 709 | 50 y 0 mo | 519 | 52 y 0 mo | 190 | 44 y 6 mo | <.001 |
| (5 y 9 mo) | (3 y 9 mo) | (6 y 6 mo) | |||||
| Age at menarche, y | 688 | 13 y 0 mo | 529 | 13 y 1 mo | 159 | 12 y 10 mo | .04 |
| (1 y 7 mo) | (1 y 3 mo) | (1 y 4 mo) | |||||
| Length of reproductive life | 573 | 37 y 0 mo | 418 | 38 y 10 mo | 155 | 32 y 0 mo | <.001 |
| (5 y 8 mo) | (3 y 11 mo) | (6 y 5 mo) | |||||
| HRT use | |||||||
| Ever using HRT | <.001 | ||||||
| No | 277 | 36.40 | 247 | 42.22 | 30 | 17.05 | |
| Yes | 484 | 63.60 | 338 | 57.78 | 146 | 82.95 | |
| Unknown | 87 | 68 | 19 | ||||
| Last use of HRT | .5 | ||||||
| In the last year | 63 | 13.24 | 40 | 12.05 | 23 | 15.97 | |
| 1–5 y ago | 72 | 15.13 | 50 | 15.06 | 22 | 15.28 | |
| More than 5 y ago | 341 | 71.64 | 242 | 72.89 | 99 | 68.75 | |
| Taken HRT but last use unknown | 8 | 6 | 2 | ||||
| Total length of HRT use, y | <.001 | ||||||
| <1 | 50 | 10.57 | 38 | 11.48 | 12 | 8.45 | |
| 1–2 | 79 | 16.70 | 71 | 21.45 | 8 | 5.63 | |
| 3–4 | 78 | 16.49 | 54 | 16.31 | 24 | 16.90 | |
| 5–6 | 67 | 14.16 | 39 | 11.78 | 28 | 19.72 | |
| 7–8 | 67 | 14.16 | 42 | 12.69 | 25 | 17.61 | |
| 9–10 | 53 | 11.21 | 42 | 12.69 | 11 | 7.75 | |
| 11–12 | 35 | 7.40 | 27 | 8.16 | 8 | 5.63 | |
| ≥13 | 44 | 9.30 | 18 | 5.44 | 26 | 18.31 | |
| Unknown length | 11 | 7 | 4 | ||||
| Current smoker | |||||||
| No | 760 | 90.15 | 585 | 90.14 | 175 | 90.21 | >.9 |
| Yes | 83 | 9.85 | 64 | 9.86 | 19 | 9.79 | |
| Unknown | 5 | 4 | 1 | ||||
| Adult social class | |||||||
| Nonmanual | 680 | 80.28 | 534 | 81.90 | 146 | 74.87 | .03 |
| Manual | 167 | 19.72 | 118 | 18.10 | 49 | 25.13 | |
| Unknown | 1 | 1 | 0 | ||||
a
Sample excludes 13 women whose periods ceased because of medical treatment (eg, chemotherapy) and five women who had been insufficiently followed up to determine menopause type.