Table 3.
Incidence and adjusted hazard ratios for hip fracture by levels of serum OC and CTX
| Incident fracture (n) | Unadjusted incidence per 1000 PY (95% CI) | Model 1 | Model 2 | Model 3 | Model 4 | |
|---|---|---|---|---|---|---|
| HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | |||
| Osteocalcin | ||||||
| Quartile 1 (≤17.0 ng/mL) | 62 | 10.99 (8.57–14.09) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) |
| Quartile 2 (>17.0–23.0 ng/mL) | 78 | 14.94 (11.97–18.65) | 1.27 (0.91–1.77) | 1.32 (0.91–1.90) | 1.34 (0.91–1.98) | 1.36 (0.92–2.02) |
| Quartile 3 (>23.0–30.0 ng/mL) | 72 | 13.50 (10.72–17.01) | 1.12 (0.80–1.58) | 1.16 (0.80–1.68) | 1.23 (0.82–1.85) | 1.23 (0.82–1.84) |
| Quartile 4 (>30.0 ng/mL) | 76 | 16.02 (12.79–20.05) | 1.20 (0.85–1.69) | 1.16 (0.79–1.70) | 1.30 (0.86–1.97) | 1.30 (0.86–1.98) |
| Per SD* increment (<19.3 ng/mL) | 1.54 (0.89–2.66) | 1.54 (0.84–2.85) | 1.70 (0.90–3.21) | 1.72 (0.91–3.25) | ||
| Per SD* increment (≥19.3 ng/mL) | 0.96 (0.82–1.12) | 0.94 (0.80–1.11) | 0.98 (0.82–1.16) | 0.97 (0.82–1.15) | ||
| CTX (ng/mL) | ||||||
| Quartile 1 (≤0.23 ng/mL) | 60 | 10.61 (8.24–13.67) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) | 1.00 (Ref.) |
| Quartile 2 (>0.23–0.37 ng/mL) | 75 | 13.97 (11.14–17.52) | 1.16 (0.83–1.64) | 1.22 (0.84–1.76) | 1.33 (0.90–1.97) | 1.39 (0.93–2.06) |
| Quartile 3 (>0.37–0.52 ng/mL) | 82 | 16.12 (12.99–20.02) | 1.42 (1.01–1.98) | 1.43 (0.99–2.07) | 1.64 (1.11–2.43) | 1.63 (1.10–2.43) |
| Quartile 4 (>0.52 ng/mL) | 71 | 14.69 (11.64–18.54) | 1.18 (0.83–1.68) | 1.11 (0.75–1.64) | 1.33 (0.87–2.02) | 1.33 (0.87–2.04) |
| Per SD† increment (<0.43 ng/mL) | 1.34 (1.03–1.76) | 1.36 (1.01–1.83) | 1.53 (1.11–2.10) | 1.52 (1.10–2.09) | ||
| Per SD† increment (≥0.43 ng/mL) | 0.86 (0.69–1.06) | 0.79 (0.63–0.99) | 0.81 (0.64–1.03) | 0.80 (0.63–1.01) |
CI, confidence interval; PY, person years.
*
SD=10.75 ng/mL
†
SD=0.23 ng/mL
Model 1: adjusted for age, race, field center and season.
Model 2 additionally adjusted for BMI, education, smoking status, alcohol consumption, physical activity, estrogen replacement therapy.
Model 3 additionally adjusted for systolic blood pressure, anti-hypertensive therapy, diabetes, calcium supplementation, LDLc, HDLc, triglycerides, prevalent CHD, prevalent CHF, prevalent claudication, prevalent AF, prevalent stroke/TIA, eGFR, and C-reactive protein.
Model 4 additionally adjusted for ADL impairment, cognitive impairment and fall history.