Table 3.
Association between serum 25(OH)D, DBP, and the 25(OH)D:DBP molar ratio and lung cancer survival in stratified models, Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study.
| Quartile 1 HR (95% CI) |
Quartile 2 HR (95% CI) |
Quartile 3 HR (95% CI) |
Quartile 4 HR (95% CI) |
p-trend | p-interaction | |
|---|---|---|---|---|---|---|
| Season-specific 25(OH)Da | ||||||
| DBP <median | ||||||
| Deaths/Total cases | 58/62 | 49/61 | 54/62 | 41/55 | 0.56 | |
| Model 1b | 1.00 (Reference) | 0.66 (0.45, 0.97) | 0.78 (0.54, 1.14) | 0.85 (0.56, 1.27) | 0.81 | |
| Model 2c | 1.00 (Reference) | 0.72 (0.47, 1.10) | 0.79 (0.51, 1.21) | 0.80 (0.51, 1.27) | 0.58 | |
| DBP ≥median | ||||||
| Deaths/Total cases | 46/54 | 53/59 | 53/61 | 61/66 | ||
| Model 1b | 1.00 (Reference) | 1.18 (0.79, 1.75) | 0.88 (0.59, 1.32) | 1.00 (0.68, 1.47) | 0.70 | |
| Model 2c | 1.00 (Reference) | 1.49 (0.96, 2.33) | 0.92 (0.59, 1.45) | 1.16 (0.76, 1.76) | 0.89 | |
| DBP | ||||||
| 25(OH)D <median | ||||||
| Deaths/Total cases | 56/64 | 51/59 | 49/57 | 50/56 | 0.20 | |
| Model 1b | 1.00 (Reference) | 0.92 (0.63, 1.35) | 1.13 (0.77, 1.66) | 1.35 (0.92, 1.98) | 0.08 | |
| Model 2c | 1.00 (Reference) | 0.85 (0.56, 1.29) | 0.91 (0.59, 1.41) | 1.36 (0.88, 2.09) | 0.17 | |
| 25(OH)D ≥median | ||||||
| Deaths/Total cases | 47/56 | 48/61 | 60/63 | 54/64 | ||
| Model 1b | 1.00 (Reference) | 0.74 (0.49, 1.11) | 1.22 (0.83, 1.79) | 0.79 (0.53, 1.17) | 0.73 | |
| Model 2c | 1.00 (Reference) | 0.85 (0.54, 1.34) | 1.39 (0.88, 2.17) | 0.76 (0.49, 1.16) | 0.43 | |
|
25(OH)D:DBP molar ratio DBP <median |
||||||
| Deaths/Total cases | 35/38 | 42/50 | 56/64 | 69/88 | 0.42 | |
| Model 1b | 1.00 (Reference) | 0.68 (0.43, 1.07) | 0.86 (0.56, 1.32) | 0.85 (0.56, 1.29) | 0.93 | |
| Model 2c | 1.00 (Reference) | 0.55 (0.33, 0.91) | 0.87 (0.53, 1.41) | 0.76 (0.48, 1.22) | 0.95 | |
| DBP ≥median | ||||||
| Deaths/Total cases | 72/82 | 61/70 | 52/56 | 28/32 | ||
| Model 1b | 1.00 (Reference) | 0.79 (0.56, 1.12) | 0.89 (0.62, 1.27) | 0.81 (0.52, 1.27) | 0.46 | |
| Model 2c | 1.00 (Reference) | 0.78 (0.54, 1.13) | 0.82 (0.55, 1.24) | 0.82 (0.50, 1.34) | 0.43 |
HR = hazard ratio; CI = confidence interval; 25(OH)D = 25-hydroxyvitamin D; DBP = vitamin D binding protein.
Cutpoints for season specific quartiles (nmol/L): Winter (November - April) = Q1: <17.8, Q2: 17.8 - <25.3, Q3: 25.3 - <40.8, Q4: ≥40.8; Summer (May - October) = Q1: <29.5, Q2: 29.5 - <45.1, Q3: 45.1 - <60.8, Q4: ≥60.8.
Adjusted for age at randomization and date of blood collection.
Adjusted for age at randomization, date of blood collection cigarettes per day, total years smoked, BMI, total serum cholesterol, calcium intake, energy intake, alcohol intake, fat intake, trial supplementation (α-tocopherol: yes/no; β-carotene: yes/no), family history of lung cancer, stage at diagnosis, and age at diagnosis.