Table 3.

Age-adjusted and variable-adjusted ORs and 95% CIs of baseline serum IGF-I, IGF-II, IGFBP-3, and IGF-I/IGFBP-3 molar ratio concentrations and pancreatic cancer among 187 cases and 374 matched control samples

Quartile of serum IGF-I concentration, ng/mL*
Q1Q2Q3Q4PtrendContinuous
Men<151.4>151.4 to <191.9>191.9 to <237.8>237.8
    Case/Controls (n)25/6531/6033/5832/59
    Crude OR (95% CI)1.00 (reference)1.41 (0.73-2.74)1.59 (0.81-3.12)1.51 (0.77-2.97)0.241.09 (0.94-1.26)
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.34 (0.68-2.65)1.39 (0.69-2.82)1.56 (0.78-3.14)0.221.09 (0.94-1.27)
Women<106.4>106.4 to <144.1>144.1 to <186.8>186.8
    Case/Controls (n)14/3520/3014/3618/31
    Crude OR (95% CI)1.00 (reference)1.82 (0.74-4.49)0.99 (0.41-2.36)1.58 (0.64-3.92)0.661.04 (0.84-1.27)
    Smoking-adjusted OR (95% CI)§1.00 (reference)2.12 (0.82-5.45)0.95 (0.39-2.34)1.74 (0.67-4.51)0.681.03 (0.83-1.27)
Combined Characteristics
    Case/Controls (n)39/10051/8946/9551/90
    Crude OR (95% CI)1.00 (reference)1.53 (0.90-2.60)1.29 (0.76-2.19)1.53 (0.89-2.62)0.23
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.57 (0.91-2.71)1.19 (0.69-2.06)1.58 (0.91-2.76)0.25
Quartile of serum IGFBP-3 concentration, ng/mL
Q1Q2Q3Q4PtrendContinuous
Men<2,977.6>2,977.6 to <3,526.6>3,526.6 to <4,181.2>4,181.2
    Case/Controls (n)28/6236/5529/6228/63
    Crude OR (95% CI)1.00 (reference)1.44 (0.77-2.69)1.04 (0.55-1.96)0.98 (0.50-1.95)0.71.01 (0.86-1.18)
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.55 (0.81-2.96)0.96 (0.50-1.86)1.03 (0.51-2.09)0.731.01 (0.86-1.19)
Women<3,236.8>3,236.8 to <3,922.7>3,922.7 to <4,481.0>4,481.0
    Case/Controls (n)17/3216/3417/3316/33
    Crude OR (95% CI)1.00 (reference)0.89 (0.38-2.08)0.97 (0.41-2.31)0.92 (0.41-2.07)0.880.96 (0.79-1.17)
    Smoking-adjusted OR (95% CI)§1.00 (reference)0.78 (0.33-1.87)0.92 (0.38-2.28)0.77 (0.32-1.83)0.630.94 (0.76-1.15)
Combined Characteristics
    Case/Controls (n)45/9252/9146/9444/97
    Crude OR (95% CI)1.00 (reference)1.17 (0.71-1.93)1.00 (0.60-1.68)0.92 (0.55-1.56)0.62
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.16 (0.69-1.95)0.95 (0.55-1.61)0.88 (0.51-1.51)0.47
Quartile of serum IGF-II concentration, ng/mL
Q1Q2Q3Q4PtrendContinuous
Men<1,339.3>1,339.3 to <1,576.6>1,576.6 to <1,831.8>1,831.8
    Case/Controls (n)29/6137/5431/6024/67
    Crude OR (95% CI)1.00 (reference)1.40 (0.76-2.60)1.07 (0.56-2.06)0.70 (0.34-1.42)0.20.99 (0.85-1.15)
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.40 (0.74-2.65)1.01 (0.51-1.99)0.75 (0.36-1.56)0.290.99 (0.86-1.15)
Women<1,452.5>1,452.5 to <1,741.8>1,741.8 to <1,999.7>1,999.7
    Case/Controls (n)14/3521/2915/3516/33
    Crude OR (95% CI)1.00 (reference)1.79 (0.77-4.16)1.08 (0.44-2.63)1.21 (0.51-2.86)0.960.95 (0.78-1.15)
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.75 (0.73-4.17)1.05 (0.43-2.60)1.12 (0.45-2.77)0.910.93 (0.76-1.14)
Q1Q2Q3Q4Ptrend
Combined Characteristics
    Case/Controls (n)43/9558/8346/9640/100
    Crude OR (95% CI)1.00 (reference)1.52 (0.92-2.51)1.05 (0.62-1.77)0.87 (0.50-1.49)0.32
    Smoking-adjusted OR (95% CI)§1.00 (reference)1.49 (0.89-2.49)1.01 (0.59-1.72)0.86 (0.49-1.50)0.31
Quartile of serum IGF-I/IGFBP-3 concentration, ng/mL
Q1Q2Q3Q4PtrendContinuous
Men≤0.17>0.17 to ≤0.20>0.20 to ≤0.23>0.23
    Case/Controls (n)27/6323/6838/5333/58
    Crude OR (95% CI)1.00 (reference)0.79 (0.39-1.58)1.68 (0.89-3.19)1.41 (0.72-2.77)0.101.16 (0.98-1.36)
    Smoking-adjusted OR (95% CI)§1.00 (reference)0.66 (0.32-1.36)1.52 (0.78-2.96)1.39 (0.69-2.80)0.101.16 (0.98-1.38)
Women≤0.12>0.12 to ≤0.13>0.13 to ≤0.16>0.16
    Case/Controls (n)16/3313/3718/3219/30
    Crude OR (95% CI)1.00 (reference)0.72 (0.29-1.79)1.23 (0.49-3.11)1.42 (0.57-3.53)0.331.03 (0.98-1.09)
    Smoking-adjusted OR (95% CI)§1.00 (reference)0.60 (0.23-1.52)1.15 (0.45-2.94)1.47 (0.58-3.75)0.291.04 (0.98-1.10)
Combined Characteristics
    Case/Controls (n)44/10630/8261/9752/89
    Crude OR (95% CI)1.00 (reference)0.89 (0.50-1.59)1.56 (0.50-1.59)1.51 (0.88-2.57)0.04
    Smoking-adjusted OR (95% CI)§1.00 (reference)0.79 (0.43-1.44)1.44 (0.86-2.41)1.54 (0.89-2.66)0.04
  • *Sex-specific quartiles based on IGF-I, IGF-II, IGFBP-3, and IGF-I/IGFBP-3 molar ratio concentration cut points observed separately for men and women in the study population at baseline.

  • There was no interaction by sex for IGF-I, IGFBP-3, IGF-II, and IGF-I/IGFBP-3 molar ratio (P = 0.94, P = 0.84, P = 0.72, and P = 0.84, respectively).

  • Crude OR adjusted for matching variables (age, race, sex, and date of blood draw based on 2-month blocks).

  • §Adjusted for smoking (never, former quit >15 y ago, former quit <15 y ago, current).