Table 1.
Anthropometric, Serum, and Bone Density/Structural Parameters in the Study Subjects
| Postmenopausal | ||||
|---|---|---|---|---|
| All women | Premenopausal | Not on HRT | On HRT | |
| N | 275 | 90 | 125 | 60 |
| Age (years) | 57.9 ± 17.7 | 38.3 ± 9.0 | 69.3 ± 12.2*** | 63.7 ± 10.6***†† |
| Anthropometric parameters | ||||
| Height (m) | 162.2 ± 6.5 | 164.4 ± 5.7 | 161.4 ± 6.7** | 160.8 ± 6.2*** |
| Weight (kg) | 73.2 ± 16.3 | 71.6 ± 16.5 | 75.9 ± 16.3 | 70.1 ± 15.3† |
| BMI (kg/m2) | 27.8 ± 5.7 | 26.4 ± 5.7 | 29.0 ± 5.3** | 27.2 ± 6.1† |
| Lean mass (kg) | 35.8 ± 4.8 | 37.5 ± 4.4 | 35.2 ± 5.1** | 34.4 ± 4.0*** |
| Fat mass (kg) | 33.6 ± 12.5 | 30.6 ± 13.9 | 36.7 ± 10.8*** | 31.7 ± 12.6†† |
| Serum parameters | ||||
| Serotonin (ng/mL) | 84.9 ± 52.3 | 95.0 ± 54.5 | 78.7 ± 52.6* | 82.6 ± 46.6 |
| Calcium (mg/dL) | 9.4 ± 0.4 | 9.3 ± 0.3 | 9.6 ± 0.4*** | 9.4 ± 0.3†† |
| Phosphorus (mg/dL) | 3.5 ± 0.4 | 3.5 ± 0.5 | 3.6 ± 0.4* | 3.5 ± 0.3 |
| 25(OH)D (ng/mL) | 22.3 ± 10.1 | 26.1 ± 12.9 | 20.2 ± 7.9*** | 20.8 ± 8.1** |
| PTH (pmol/L) | 3.6 ± 1.6 | 3.0 ± 1.2 | 4.0 ± 1.7*** | 3.7 ± 1.7** |
| Osteocalcin (ng/mL) | 19.7 ± 8.7 | 19.8 ± 7.8 | 21.3 ± 9.5 | 16.2 ± 7.1**††† |
| PINP (µg/L) | 37.8 ± 17.6 | 38.7 ± 16.5 | 41.4 ± 19.3 | 29.1 ± 12.0***††† |
| CTX (ng/mL) | 0.49 ± 0.26 | 0.48 ± 0.26 | 0.56 ± 0.26* | 0.38 ± 0.21**††† |
| DXA BMD parameters | ||||
| Total-body BMD (g/cm2) | 1.14 ± 0.11 | 1.19 ± 0.09 | 1.11 ± 0.12*** | 1.13 ± 0.10*** |
| Spine BMD (g/cm2) | 1.11 ± 0.16 | 1.16 ± 0.15 | 1.08 ± 0.16*** | 1.09 ± 0.15** |
| Central QCT parameters | ||||
| Femur neck | ||||
| Total vBMD (mg/cm3) | 334 ± 74 | 391 ± 58 | 296 ± 59*** | 325 ± 67***†† |
| Trabecular vBMD (mg/cm3) | 214 ± 59 | 259 ± 46 | 184 ± 49*** | 207 ± 51***†† |
| Cortical vBMD (mg/cm3) | 581 ± 83 | 633 ± 70 | 548 ± 75*** | 567 ± 77*** |
| Vertebrae | ||||
| Trabecular vBMD (mg/cm3) | 154 ± 44 | 190 ± 27 | 130 ± 39*** | 152 ± 36***††† |
| HRpQCT parametersa | ||||
| BV/TV | 0.126 ± 0.033 | 0.136 ± 0.027 | 0.119 ± 0.035** | 0.124 ± 0.033* |
| TbN (1/mm) | 2.50 ± 0.26 | 2.56 ± 0.19 | 2.49 ± 0.31 | 2.46 ± 0.23** |
| TbTh (mm) | 0.050 ± 0.010 | 0.053 ± 0.008 | 0.047 ± 0.011*** | 0.050 ± 0.010 |
| TbSp (mm) | 0.354 ± 0.054 | 0.340 ± 0.035 | 0.362 ± 0.066** | 0.360 ± 0.047** |
Data are mean ± SD. BMI = body mass index; 25(OH)D = 25-hydroxyvitamin D; PTH = parathyroid hormone; PINP = amino-terminal propeptide of type I collagen; CTX = cross-linked C-telopeptide of type I collagen; DXA = dual-energy X-ray absorptiometry; BMD = bone mineral density; vBMD = volumetric BMD; BV/TV = bone volume/total volume; TbN = trabecular number; TbTh = trabecular thickness; TbSp = trabecular separation.
a
As noted in the “Methods,” the HRpQCT data were available in a subset of the women.
*
P < .05
**
P < .01
***
P < .001 versus premenopausal women
†
P < .05
††
P < .01
†††
P < .001 versus postmenopausal women not on HT.