Table 2.
Baseline characteristics of participants subdivided according to age
| Age 55–65 n = 105 | Age 65–75 n = 220 | P-value | |
|---|---|---|---|
| Anthropomorphic variables: | |||
| Age (years) | 59.0 ± 0.3 | 69.3 ± 0.2 | |
| Years since menopause | 9.7 ± 0.5 | 21.2 ± 0.4 | |
| Weight (kg) | 67.4 ± 1.0 | 72.8 ± 0.8 | 0.0001 |
| Height (cm) | 163 ± 0.6 | 161 ± 0.4 | 0.003 |
| BMI (kg/m2) | 25.4 ± 0.4 | 28.1 ± 0.3 | 0.0001 |
| Calcium intake (mg/day) | 816 ± 34 | 858 ± 27 | 0.4 |
| Non-smoking (%) | 88 | 87 | 0.9 |
| Bone density characteristics: | |||
| DXA-BMD (g/cm2) of: femoral neck | 0.716 ± 0.010 | 0.689 ± 0.006 | 0.02 |
| Total hip | 0.871 ± 0.012 | 0.842 ± 0.007 | 0.03 |
| Lumbar L2-L4 | 0.940 ± 0.015 | 0.925 ± 0.011 | 0.4 |
| BMC (g) of: femoral neck | 3.69 ± 0.06 | 3.55 ± 0.03 | 0.02 |
| Total hip | 31.4 ± 0.6 | 30.7 ± 0.3 | 0.3 |
| Lumbar L2-L4 | 44.0 ± 0.9 | 42.1 ± 0.6 | 0.1 |
| Hip geometry: | |||
| Mean FNW (cm): | 3.44 ± 0.022 | 3.44 ± 0.016 | 0.9 |
| HAL (cm): | 11.8 ± 0.08 | 11.6 ± 0.06 | 0.03 |
| Bone strength indices: | |||
| CSI (g/kg m): | 3.75 ± 0.068 | 3.31 ± 0.039 | 0.0001 |
| BSI (g/kg m): | 1.09 ± 0.022 | 0.98 ± 0.013 | 0.0001 |
| ISI (g/kg m): | 0.27 ± 0.005 | 0.24 ± 0.003 | 0.0001 |
| Serum markers for bone metabolism: | |||
| c-OC (ng/mL) | 5.9 ± 0.2 | 6.3 ± 0.2 | 0.2 |
| uc-OC (ng/mL) | 3.3 ± 0.2 | 3.2 ± 0.1 | 0.8 |
| t-OC (ng/mL) | 13.9 ± 0.6 | 12.8 ± 0.4 | 0.1 |
| BAP (ng/mL) | 21.8 ± 0.8 | 24.1 ± 0.7 | 0.05 |
| NTX (nM) | 11.0 ± 0.3 | 10.6 ± 0.2 | 0.2 |
| 25-OH D (nM) | 76.5 ± 2.7 | 66.3 ± 2.3 | 0.005 |
| Urine markers for bone metabolism: | |||
| creatinine (mmol/L) | 3.5 ± 0.3 | 3.6 ± 0.2 | 0.8 |
| DPD / creat (nmol/mmol) | 8.2 ± 0.2 | 7.1 ± 0.2 | 0.0001 |
| Calcium / creat (mmol/mmol) | 0.29 ± 0.02 | 0.29 ± 0.01 | 0.9 |
The differences in all age-related variables were highly significant. All data are given±SE.