Table 3

Means and correlations of IGFBP-3 levels with mammographic breast density


Adjusted means of percent density (percentage)a
Adjusted means of absolute density (cm2)a,b

Levels of IGFBP-3
Intactc
Fragmentedd
Totale
Intactc
Fragmentedd
Totale
     Quartile 1 (n = 185)
42.2
45.3
44.5
48.6
48.3
49.4
     Quartile 2 (n = 184)
42.9
44.3
44.7
46.3
48.0
48.6
     Quartile 3 (n = 184)
40.4
40.3
40.7
45.7
45.9
45.0
     Quartile 4 (n = 184)
44.0
39.6
39.6
45.5
43.9
43.1
     rf (P)
0.075 (0.04)
-0.171 (< 0.0001)
-0.151 (< 0.0001)
-0.010 (0.79)
-0.092 (0.01)
-0.094 (0.01)
     rf (P)a
0.031 (0.40)
-0.105 (0.004)
-0.095 (0.01)
-0.029 (0.43)
-0.066 (0.07)
-0.075 (0.04)
     rf (P)g
0.022 (0.55)
-0.112 (0.003)
-0.104 (0.005)
-0.042 (0.26)
-0.078 (0.04)
-0.090 (0.02)

aMeans and correlations are adjusted for age, body mass index, waist-to-hip ratio, alcohol intake, energy intake, physical activity, parity, smoking status, and total IGF-I levels. bMeans of absolute density are presented as back-transformed values; square-root-transformed absolute density is used in the correlation. cQuartiles of intact IGFBP-3 are ≤883.80, 883.81 to 1,021.00, 1,021.01 to 1,170.50, and > 1,170.50 ng/mL. dQuartiles of fragmented IGFBP-3 are ≤3,137.50, 3,137.51 to 3,662.50, 3,662.51 to 4,263.00, and > 4,263.00 ng/mL. eQuartiles of total IGFBP-3 are ≤4,183.0, 4,183.1 to 4,695.0, 4,695.1 to 5,290.0, and > 5,290.0 ng/mL. fPearson correlation between continuous variables; adjusted correlations are partial Pearson coefficients. gCorrelations are adjusted for age, body mass index, waist-to-hip ratio, alcohol intake, energy intake, physical activity, parity, smoking status, total IGF-I levels, age at menarche, number of full-term pregnancies, age at first full-term pregnancy, lactation, family history of breast cancer, number of breast biopsies, education, past use of oral contraceptives, past use of hormone replacement therapy, and height.

Diorio et al. Breast Cancer Research 2008 10:R42   doi:10.1186/bcr2093