Inverse association between estrogen receptor-α DNA methylation and breast composition in adolescent Chilean girls

Table 2 ER-α methylation at B4 is inversely associated with B4 total BV in Chilean girls enrolled in GOCS

Stage label	Relative change in geometric mean BV (95% CI)
Stage label	Model 1^a	Model 2^b	Model 3^c
Tanner 2
Quartiles^d
Q2	0.91 (0.79–1.05)	0.89 (0.76–1.03)	0.89 (0.77–1.04)
Q3	1.04 (0.90–1.21)	1.05 (0.90–1.22)	1.05 (0.90–1.22)
Q4	1.03 (0.89–1.19)	1.02 (0.88–1.19)	1.03 (0.89–1.20)
Linear model^e
	1.03 (0.96–1.09)	1.01 (0.95–1.08)	1.02 (0.95–1.09)
Tanner 4
Quartiles^d
Q2	0.91 (0.82–1.00)	0.95 (0.86–1.06)	0.95 (0.86–1.06)
Q3	1.03 (0.93–1.14)	0.99 (0.89–1.10)	0.99 (0.89–1.10)
Q4	0.94 (0.85–1.04)	0.92 (0.83–1.02)	0.92 (0.83–1.02)
Linear model^e
	0.98 (0.94–1.03)	0.96 (0.91–1.00)	0.96 (0.91–1.00)
Tanner 2 (2 and 4)^f
Quartiles^d
Q2	0.89 (0.77–1.03)	0.90 (0.77–1.05)	0.90 (0.77–1.05)
Q3	1.07 (0.92–1.24)	1.08 (0.92–1.27)	1.08 (0.92–1.27)
Q4	1.00 (0.86–1.17)	1.02 (0.87–1.19)	1.01 (0.86–1.19)
Linear model^e
	1.02 (0.95–1.09)	1.00 (0.94–1.08)	1.00 (0.93–1.08)
Tanner 4 (2 and 4)^g
Quartiles^d
Q2	0.93 (0.81–1.07)	0.95 (0.82–1.10)	0.95 (0.82–1.10)
Q3	1.10 (0.94–1.28)	1.03 (0.88–1.21)	1.03 (0.88–1.21)
Q4	0.89 (0.77–1.04)	0.85 (0.72–0.99)*	0.85 (0.72–0.99) *
Linear model^e
	0.98 (0.91–1.04)	0.93 (0.86–1.00)*	0.93 (0.86–1.00)*

^aAssociation with mean ER-α methylation adjusting for fat percentage at breast density measurement
^bAssociation with cell composition corrected mean ER-α methylation adjusting for fat percentage at breast density measurement
^cModel 2 additionally adjusted for age at breast density measurement and maternal education
^dQuartiles for Tanner 2 methylation: Q1 [1.17, 4.05], Q2 (4.05, 6.04], Q3 (6.04, 8.85], Q4 (8.85, 29.30]; quartiles for Tanner 2 methylation after correction for cellular heterogeneity: Q1 [0.98, 3.49], Q2 (3.49, 5.03], Q3 (5.03, 7.34], Q4 (7.34, 24.8]. Quartiles for Tanner 4 methylation: Q1 [1.10, 4.27], Q2 (4.27, 7.05], Q3 (7.05, 9.37], Q4 (9.37, 32.00]; quartiles for Tanner 4 methylation after correction for cellular heterogeneity: Q1 [0.78, 3.37], Q2 (3.37, 5.28], Q3 (5.28, 6.96], Q4 (6.96, 23.60]
^eReporting relative change in geometric mean BV per doubling of percent methylation
^fModeling B2 and B4 ER-α methylation simultaneously, reporting association with B2 ER-α methylation
^gModeling B2 and B4 ER-α methylation simultaneously, reporting association with B4 ER-α methylation
*p<0.05, Wald test

ISSN: 1868-7083