Table 2.
Odds ratios and 95% confidence intervals of advanced and lethal prostate cancer by quartile of total 25-hydroxyvitamin D, bioavailable 25-hydroxyvitamin D, and vitamin D binding protein
| Quartile of biomarker | ptrend | ||||
|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||
| Advanced prostate cancer | |||||
| Total 25(OH)D | |||||
| Median (range), ng/mL | 15.60 (≤18.49) | 21.45 (18.54–24.28) | 27.95 (24.31–30.47) | 37.00 (≥30.78) | |
| No. of cases/controls | 44/38 | 54/39 | 33/39 | 24/39 | |
| Base model, OR (95% CI)1 | 1 | 1.19 (0.63–2.26) | 0.78 (0.40–1.54) | 0.54 (0.27–1.08) | 0.03 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 1.24 (0.64–2.40) | 0.78 (0.38–1.57) | 0.50 (0.24–1.03) | 0.02 |
| Model further adjusted for VDBP, OR (95% CI) | 1 | 1.23 (0.64–2.37) | 0.79 (0.39–1.59) | 0.49 (0.24–1.01) | 0.02 |
| Bioavailable 25(OH)D3 | |||||
| Median (range), ng/mL | 1.787 (≤2.253) | 2.626 (2.255–2.887) | 3.470 (2.888–3.980) | 5.067 (≥4.008) | |
| No. of cases/controls | 52/38 | 33/39 | 33/39 | 37/39 | |
| Base model, OR (95% CI)1 | 1 | 0.59 (0.30–1.15) | 0.58 (0.29–1.14) | 0.67 (0.35–1.27) | 0.21 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 0.47 (0.22–0.97) | 0.50 (0.24–1.02) | 0.58 (0.30–1.15) | 0.14 |
| VDBP | |||||
| Median (range), µg/mL | 138.8 (≤186.6) | 212.8 (188.0–239.6) | 262.8 (239.8–296.0) | 346.7 (≥298.0) | |
| No. of cases/controls | 50/39 | 38/39 | 34/39 | 34/39 | |
| Base model, OR (95% CI)1 | 1 | 0.69 (0.35–1.36) | 0.61 (0.30–1.21) | 0.59 (0.29–1.21) | 0.14 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 0.66 (0.33–1.31) | 0.61 (0.30–1.23) | 0.62 (0.30–1.30) | 0.21 |
| Model further adjusted for 25(OH)D, OR (95% CI) | 1 | 0.64 (0.31–1.29) | 0.55 (0.27–1.14) | 0.59 (0.28–1.26) | 0.16 |
| Lethal prostate cancer | |||||
| Total 25(OH)D | |||||
| Median (range), ng/mL | 15.63 (≤18.49) | 21.32 (18.54–24.22) | 27.55 (24.31–30.32) | 37.00 (≥30.78) | |
| No. of cases/controls | 35/28 | 36/29 | 25/30 | 19/28 | |
| Base model, OR (95% CI)1 | 1 | 0.95 (0.46–1.96) | 0.69 (0.33–1.47) | 0.57 (0.26–1.22) | 0.09 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 1.07 (0.49–2.34) | 0.63 (0.28–1.40) | 0.50 (0.22–1.15) | 0.04 |
| Model further adjusted for VDBP, OR (95% CI) | 1 | 1.07 (0.49–2.34) | 0.63 (0.28–1.40) | 0.50 (0.22–1.15) | 0.04 |
| Bioavailable 25(OH)D3 | |||||
| Median (range), ng/mL | 1.802 (≤2.253) | 2.656 (2.255–2.887) | 3.453 (2.888–3.980) | 5.331 (≥4.087) | |
| No. of cases/controls | 41/27 | 24/29 | 23/29 | 27/30 | |
| Base model, OR (95% CI)1 | 1 | 0.49 (0.22–1.11) | 0.47 (0.21–1.05) | 0.57 (0.27–1.21) | 0.13 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 0.38 (0.16–0.95) | 0.34 (0.14–0.83) | 0.45 (0.20–1.02) | 0.05 |
| VDBP | |||||
| Median (range), µg/mL | 140.6 (≤186.6) | 213.3 (188.0–237.9) | 262.8 (239.8–296.0) | 348.7 (≥299.4) | |
| No. of cases/controls | 39/33 | 24/25 | 28/31 | 25/27 | |
| Base model, OR (95% CI)1 | 1 | 0.78 (0.36–1.69) | 0.71 (0.33–1.53) | 0.72 (0.32–1.63) | 0.39 |
| Multivariable-adjusted model, OR (95% CI)2 | 1 | 0.65 (0.29–1.50) | 0.70 (0.32–1.55) | 0.85 (0.35–2.04) | 0.62 |
| Model further adjusted for 25(OH)D, OR (95% CI) | 1 | 0.65 (0.28–1.54) | 0.62 (0.27–1.39) | 0.79 (0.32–1.95) | 0.48 |
Abbreviations: 25(OH)D, 25-hydroxyvitamin D; CI, confidence interval; OR, odds ratio; VDBP, vitamin D binding protein.
OR (95% CI) from conditional logistic models conditioned on matching factors.
OR (95% CI) from conditional logistic models conditioned on matching factors and adjusted for family history of prostate cancer, body mass index (<25.0, 25.0–29.9, ≥30.0 kg/m2), vigorous physical activity (0, 0.1–5.9, 6.0–12.9, 13.0–25.9, ≥26.0 metabolic equivalent-h/week), and smoking status (never, past, current).
Bioavailable 25(OH)D was calculated using total 25(OH)D, VDBP, and albumin levels and a constant affinity of VDBP for 25(OH)D.