Skip to main content
. Author manuscript; available in PMC: 2014 Dec 1.
Published in final edited form as: Cancer Epidemiol Biomarkers Prev. 2014 Mar 19;23(6):976–985. doi: 10.1158/1055-9965.EPI-13-1210-T

Table 3.

Odds ratios and 95% CI for differentiated thyroid carcinoma associated with thirds and a doubling of IGF-I concentration, overall, by sub-groups, and by tumour characteristics.

Bottom third Middle third Top third Doublinga
IGF-I range (median) < 15.3 (13.0) nmol/lb 15.3 - 19.6 (17.4) nmol/lb > 19.6 (22.8) nmol/lb

OR 95% CI OR 95% CI OR 95% CI OR 95% CI Ptrend pheterogeneityc
ncase/ncontrol 105/245 101/245 139/245
Risk overalld
 Age-adjusted model 345/735 1 Ref 0.99 0.71 1.39 1.37 0.99 1.91 1.48 1.06 2.08 0.02
 Multivariable-adjusted modele 345/735 1 Ref 1.00 0.71 1.41 1.37 0.98 1.92 1.46 1.04 2.07 0.03
 Further adjusted modelf 345/735 1 Ref 1.02 0.72 1.46 1.33 0.93 1.88 1.41 0. 99 2.01 0.06
Risk in sub-groupsd
Sex
  Male 56/164 1 Ref 1.01 0.45 2.28 1.63 0.73 3.65 1.39 0.61 3.16 0.43
  Female 289/571 1 Ref 0.99 0.68 1.44 1.33 0.92 1.91 1.50 1.04 2.18 0.03 0.87
Age at blood collection (years)
  < 50 146/310 1 Ref 1.55 0.84 2.84 1.59 0.91 2.78 1.54 0.90 2.66 0.12
  ≥ 50 199/425 1 Ref 0.79 0.52 1.20 1.39 0.91 2.13 1.45 0.94 2.22 0.09 0.86
Educationg
  Less than secondary school 135/273 1 Ref 1.10 0.66 1.86 1.47 0.87 2.48 1.80 1.08 3.00 0.02
  Secondary school or more 201/436 1 Ref 0.84 0.53 1.31 1.20 0.79 1.83 1.27 0.83 1.93 0.27 0.27
Smoking
  Never 179/390 1 Ref 1.02 0.65 1.60 1.37 0.87 2.17 1.62 1.03 2.56 0.04
  Ever 161/326 1 Ref 0.96 0.58 1.58 1.39 0.87 2.24 1.39 0.88 2.20 0.16 0.62
BMI (kg/m2)
  < 25 158/347 1 Ref 0.92 0.55 1.53 1.32 0.81 2.16 1.45 0.88 2.38 0.14
  ≥ 25 187/388 1 Ref 1.05 0.67 1.64 1.44 0.92 2.26 1.55 1.00 2.42 0.05 0.84
Thyroid stimulation hormone (mIU/l)g
  < 1.27 204/365 1 Ref 1.03 0.66 1.61 1.37 0.89 2.11 1.46 0.96 2.22 0.08
  ≥ 1.27 140/366 1 Ref 1.00 0.59 1.67 1.35 0.83 2.22 1.52 0.91 2.52 0.11 0.90
Risk by tumour characteristicsd
Histological typeg
  Papillary 253/538 1 Ref 1.30 0.86 1.95 1.62 1.09 2.40 1.69 1.13 2.55 0.01
  Follicular 56/122 1 Ref 0.60 0.27 1.38 0.92 0.41 2.08 1.13 0.53 2.37 0.76 0.35
TNM stageg
  Localized 101/211 1 Ref 0.92 0.47 1.78 1.48 0.82 2.70 1.44 0.81 2.54 0.22
  More advanced 79/172 1 Ref 2.01 1.00 4.06 1.53 0.75 3.13 1.91 0.90 4.08 0.09 0.55
Years between blood collection and diagnosis
  < 5 137/293 1 Ref 0.79 0.46 1.35 1.33 0.80 2.21 1.48 0.84 2.61 0.18
  ≥ 5 208/442 1 Ref 1.15 0.74 1.80 1.42 0.92 2.20 1.48 0.97 2.26 0.07 0.99
a

OR, 95% CI, and ptrend were based on the logarithm (base2) of IGF-I concentrations (as a continuous variable) and correspond to the risk associated with a doubling in IGF-I concentration.

b

Tertile cut-points were based on the distribution controls only.

c

P values refer to likelihood ratio χ2 test between models of the linear trend in logarithm (base 2) of IGF-I concentrations with and without an interaction term with the variable of interest.

d

All analyses were logistic regression models conditioned on the matching variables and adjusted for age at blood collection (as a continuous variable).

e

The multivariable-adjusted model was adjusted for age at blood collection (as a continuous variable), height (as a continuous variable), and BMI (in fifths based on the distribution in controls).

f

The further adjusted model was in addition to age at blood collection, height, and BMI adjusted for waist to hip ratio (below and above the median based on the distribution in controls; unknown), alcohol (0; > 0 – 9; 10 – 19; ≥ 20 g/d), smoking (never; former; current; unknown), physical activity (inactive; moderately inactive; moderately active or active; unknown), education (less than secondary school; secondary school; university degree; unknown), and in women only, age at first period (< 12; 12 – 14; < 14 years; unknown), number of full term pregnancies and age at first pregnancy (nulliparous; 1 – 2 children and < 25 years; 1 – 2 children and ≥ 25 years; ≥ 3 children and < 25 years; ≥ 3 children and ≥ 25 years; unknown), and for postmenopausal women only, age at menopause (<50; ≥ 50 years; unknown).

g

Unknown for some participants.