Table 3.

Adjusted associations between IGF variables and HGCIN stratified according to median age

IGF variable and levelsCases, n (%)Controls, n (%)OR (95% CI)
Ptrend
Age-adjusted*Age, ethnicity, sexual activity, and mutual IGF-I and IGFBP-3 adjustedAge, ethnicity, sexual activity, mutual IGF-I and IGFBP-3, and HPV status adjusted
≤30 y (461 women)
IGF-I (quartiles), ng/mL
    Q1 (<294.0)66 (42.31)77 (25.25)1.00 (reference)1.00 (reference)1.00 (reference)0.016
    Q2 (294.0-353.0)32 (20.51)77 (25.25)0.50 (0.29-0.84)0.43 (0.24-0.79)0.40 (0.16-0.96)
    Q3 (353.0-424.0)27 (17.31)75 (24.59)0.42 (0.24-0.74)0.33 (0.18-0.62)0.35 (0.14-0.87)
    Q4 (>424.0)31 (19.87)76 (24.92)0.48 (0.27-0.85)0.36 (0.19-0.71)0.31 (0.12-0.76)
IGFBP-3 (quartiles), ng/mL
    Q1 (<4,714.8)38 (24.36)76 (24.92)1.00 (reference)1.00 (reference)1.00 (reference)0.729
    Q2 (4,714.8-5,204.7)45 (28.85)76 (24.92)1.19 (0.70-2.04)1.40 (0.76-2.58)1.41 (0.58-3.44)
    Q3 (5,204.7-5,787.0)40 (25.64)78 (25.57)1.04 (0.60-1.80)1.38 (0.73-2.59)1.28 (0.50-3.27)
    Q4 (>5,787.0)33 (21.15)75 (24.59)0.90 (0.51-1.61)1.29 (0.64-2.58)0.91 (0.34-2.42)
>30 y (488 women)
IGF-I (quartiles), ng/mL
    Q1 (<208.0)46 (25.59)82 (26.03)1.00 (reference)1.00 (reference)1.00 (reference)0.506
    Q2 (208.0-261.0)49 (28.32)78 (24.76)1.04 (0.67-1.74)0.99 (0.57-1.72)1.05 (0.40-2.74)
    Q3 (261.0-332.0)50 (28.90)77 (24.44)1.06 (0.62-1.79)0.94 (0.53-1.68)1.72 (0.62-4.76)
    Q4 (>332.0)28 (16.18)78 (24.76)0.55 (0.30-1.00)0.47 (0.24-0.92)0.59 (0.19-1.89)
IGFBP-3 (quartiles), ng/mL
    Q1 (<4,496.7)47 (27.17)79 (25.08)1.00 (reference)1.00 (reference)1.00 (reference)0.486
    Q2 (4,496.7-4,965.9)40 (23.12)78 (24.76)0.83 (0.49-1.41)0.89 (0.51-1.55)0.58 (0.22-1.54)
    Q3 (4,965.9-5,461.9)49 (28.32)79 (25.08)1.01 (0.60-1.69)1.15 (0.66-2.02)1.12 (0.40-3.11)
    Q4 (>5,461.9)37 (21.39)79 (25.08)0.78 (0.46-1.34)0.99 (0.55-1.80)1.24 (0.44-3.48)
  • * Analyses adjusted for age group (<22, 22-25-, 26-30) and (31-34, 35-40, 41+).

  • Analyses also adjusted for ethnicity (French Canadian, English Canadian, Other), age at first intercourse (<16, 16-17, 18, >19 y), number of sexual partners (1, 2-4, 5-8, and >8 partners), and mutual adjustment for IGF-I and IGFBP-3 according to the age-specific quartiles in the table.

  • Analyses adjusted also for HPV status (negative, low-risk HPV only, high-risk HPV except HPV-16/HPV-18, and HPV-16/HPV-18).