Table 2.

ORs and 95% CIs of baseline serum 25(OH)D and bladder cancer risk, PLCO

No. of casesNo. of controlsOR (95% CI)aOR (95% CI)bOR (95% CI)c
25(OH)D, nmol/L
 <2516170.86 (0.38–1.94)0.73 (0.29–1.84)0.74 (0.29–1.87)
 25–<37.554630.75 (0.47–1.20)0.71 (0.42–1.19)0.72 (0.43–1.23)
 37.5–<5092761.10 (0.75–1.63)1.17 (0.76–1.80)1.17 (0.76–1.80)
 50–<751581441.0 (ref)1.0 (ref)1.0 (ref)
 ≥7549640.71 (0.46–1.09)0.85 (0.53–1.35)0.85 (0.53–1.38)
Ptrendd0.500.970.99
Season-specific quartilese of 25(OH)D
 1841001.00 (0.65–1.52)0.84 (0.52–1.36)0.84 (0.51–1.38)
 2101811.43 (0.96–2.13)1.24 (0.80–1.92)1.24 (0.79–1.93)
 3103821.49 (1.00–2.21)1.29 (0.84–1.99)1.28 (0.83–1.98)
 4811011.0 (ref)1.0 (ref)1.0 (ref)
Ptrendf0.950.560.58
Residual-adjusted quartilesg of 25(OH)D
 193901.19 (0.78–1.83)1.01 (0.53–1.64)1.04 (0.63–1.71)
 291921.15 (0.77–1.70)1.11 (0.72–1.71)1.12 (0.72–1.74)
 3100831.39 (0.91–2.12)1.13 (0.71–1.81)1.13 (0.70–1.82)
 485991.0 (ref)1.0 (ref)1.0 (ref)
Ptrendf0.610.940.88
DBP, μg/mL
 Q1: <18790921.0 (ref)1.0 (ref)1.0 (ref)
 Q2: 187–<23598861.03 (0.67–1.58)0.80 (0.50–1.29)0.79 (0.49–1.28)
 Q3: 235–<29191921.18 (0.78–1.78)1.12 (0.71–1.76)1.08 (0.68–1.71)
 Q4: ≥29190941.03 (0.67–1.56)0.90 (0.57–1.42)0.85 (0.53–1.36)
Ptrendd0.710.610.58
25(OH)D:DBP molar ratio
 Q1: <9.687901.0 (ref)1.0 (ref)
 Q2: 9.6–<13.0103890.86 (0.54–1.36)0.88 (0.53–1.48)
 Q3: 13.0–<17.279951.00 (0.66–1.50)1.02 (0.65–1.60)
 Q4: ≥17.2100900.75 (0.49–1.15)0.82 (0.51–1.32)
Ptrendd0.830.90
  • aConditioned on the matching factors.

  • bConditioned on the matching factors. Further adjusted for smoking status, pack-years of smoking, dairy consumption, and use of aspirin or ibuprofen.

  • cConditioned on the matching factors. Further adjusted for smoking status, pack-years of smoking, dairy consumption, use of aspirin or ibuprofen, and mutually adjusted for 25(OH)D and DBP.

  • dMedian of each category modeled as a continuous variable.

  • eWinter quartile cutoff points (in nmol/L) = Q1: <35, Q2: 35–<49, Q3: 49–<66, Q4: ≥66; summer quartile cutoff points (in nmol/L) = Q1: <48, Q2: 48–<60, Q3: 60–<73, Q4: ≥73.

  • fOrdinal variable for quartile group modeled as a continuous variable.

  • gCutoff points for residual-adjusted quartiles were Q1: <54.5, Q2: 54.5–<54.8, Q3: 54.8–<55.0, Q4: ≥55.0, created by calculating residuals from the regression line of log-transformed 25(OH)D against calendar week of blood collection and adding them to the mean 25(OH)D level.