Table 1.
Characteristics of participants [mean ± SD or N (%)] by quartiles of sex hormone binding globulin (SHBG)
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | ||
|---|---|---|---|---|---|
| < 35.7 nmol/liter | ≥35.7–<46.5 nmol/liter | ≥46.5–<59.3 nmol/liter | ≥59.3 nmol/liter | P value | |
| Age | 71.8 ± 5.0 | 73.2 ± 5.5 | 74.02 ± 6.0 | 75.7 ± 6.4 | <0.001 |
| Race/ethnicity | |||||
| Caucasian | 321 (88.4) | 345 (93.0) | 328 (89.4) | 326 (88.6) | 0.161 |
| African American | 15 (4.1) | 11 (3.0) | 16 (4.4) | 10 (2.7) | |
| Asian, Hispanic or Other | 27 (7.4) | 15 (4.0) | 23 (6.3) | 32 (8.7) | |
| BMI (kg/m2) | 28.9 ± 3.8 | 27.7 ± 4.0 | 26.7 ± 3.1 | 26.2 ± 3.6 | <0.001 |
| Height (cm) | 174.7 ± 6.3 | 174.9 ± 6.9 | 174.1 ± 7.2 | 173.9 ± 7.1 | 0.163 |
| Smoking | |||||
| Never | 116 (32.0) | 133 (35.9) | 146 (39.8) | 151 (41.0) | 0.002 |
| Past | 241 (66.4) | 224 (60.4) | 207 (56.4) | 194 (52.7) | |
| Current | 6 (1.7) | 14 (3.8) | 14 (3.8) | 23 (6.3) | |
| PASE score (activity level) | 148.7 ± 68.2 | 151.5 ± 70.8 | 143.6 ± 69.0 | 143.5 ± 67.5 | 0.299 |
| Fall history | 58 (16.0) | 73 (19.7) | 88 (24.0) | 89 (24.2) | 0.018 |
| Femoral neck BMD (g/cm2) | 0.818 ± 0.128 | 0.777 ± 0.123 | 0.785 ± 0.130 | 0.749 ± 0.122 | <0.001 |
| Lumbar spine BMD (g/cm2) | 1.080 ± 0.175 | 1.078 ± 0.194 | 1.069 ± 0.177 | 1.036 ± 0.177 | 0.003 |
| Walking speed (m/s) | 1.20 ± 0.23 | 1.20 ± 0.23 | 1.20 ± 0.22 | 1.18 ± 0.23 | 0.084 |
| Non-spine fracture after age 50 | 73 (20.2) | 87 (23.5) | 87 (23.7) | 96 (26.2) | 0.288 |
| Number of selected comorbidities* | |||||
| 0 | 166 (45.7) | 185 (49.9) | 189 (51.5) | 182 (49.5) | 0.608 |
| 1–2 | 173 (47.7) | 171 (46.1) | 161 (43.9) | 167 (45.4) | |
| 3+ | 24 (6.6) | 15( 4.0) | 17 (4.6) | 19 (5.2) | |
| Bioavailable Estradiol (pg/ml) | 15.1 ± 4.9 | 14.7 ± 4.8 | 14.2 ± 4.7 | 13.5 ± 4.7 | <0.001 |
| Estradiol (pg/ml) | 20.1 ± 6.6 | 21.7 ± 7.0 | 22.9 ± 7.5 | 25.2 ± 9.2 | <0.001 |
| Bioavailable Testosterone (ng/dl) | 179.0 ± 51.4 | 204.0 ± 57.9 | 215.0 ± 61.8 | 219.4 ± 78.0 | <0.001 |
| Testosterone (ng/dl) | 282.2 ± 83.4 | 367.9 ± 99.8 | 431.9 ± 118.7 | 535.5 ± 197.6 | <0.001 |
*
Medical conditions included self-report of a physician’s diagnosis of diabetes, stroke, low or high thyroid levels, heart attack, congestive heart failure, chronic obstructive pulmonary disease, Parkinson’s disease, and non-skin cancer.
BMD: Bone mineral density