Skip to main content

Table 2 Least squares mean and 95 % confidence interval (CI) for percent dense breast volume at the DISC06 follow-up visit according to quartile of age-specific youth body mass index (BMI) Z-score

From: Body fatness during childhood and adolescence and breast density in young women: a prospective analysis

Quartile of age-specific youth BMI Z-score:

Q1

Q2

Q3

Q4

Change in adult percent breast density per unit youth BMI Z-score

p value*

BMI at baseline visit (ages 8–10)

Model 1

40.9 (34.6, 47.2)

32.9(30.0, 35.8)

23.6 (19.6, 27.6)

13.1 (9.4, 16.8)

−11.1

<0.01

n = 182

Model 2

31.3 (25.0, 37.6)

28.9 (26.6, 31.3)

26.7 (22.1, 31.3)

23.7 (19.3, 28.0)

−2.7

<0.01

 

Model 3

31.8 (25.2, 38.4)

29.0 (26.0, 32.0)

26.2 (22.2, 30.1)

23.4 (18.0, 28.8)

−3.1

<0.01

BMI at Year 3 visit (ages 11–13)

Model 1

43.3 (36.7, 50.0)

34.6 (27.5, 41.8)

19.7 (16.8, 22.6)

12.8 (9.9, 15.7)

−12.9

<0.01

n = 170

Model 2

33.8 (27.6, 40.0)

30.8 (24.8, 36.8)

24.1 (21.5, 26.8)

21.8 (18.6, 24.9)

−5.1

<0.01

 

Model 3

34.5 (28.2, 40.7)

30.4 (26.5, 34.2)

25.0 (22.3, 26.9)

21.1 (18.6, 23.5)

−5.4

<0.01

BMI at Year 5 visit (ages 13–15)

Model 1

44.5 (38.7, 50.2)

39.0 (33.0, 44.9)

18.7 (15.0, 22.4)

9.9 (6.8, 13.0)

−15.5

<0.01

n = 153

Model 2

35.4 (30.1, 40.8)

31.8 (26.4, 37.2)

22.7 (18.6, 26.9)

21.6 (14.9, 28.2)

−6.2

<0.01

 

Model 3

34.5 (29.3, 39.7)

31.6 (19.3, 28.5)

23.9 (19.3, 28.5)

21.3 (14.8, 27.7)

−6.2

<0.01

BMI at last visit (ages 15–17)

Model 1

44.7 (37.4, 51.9)

36.0 (30.9, 41.1)

23.9 (19.9, 28.0)

11.0 (10.0, 12.0)

−14.0

<0.01

n = 159

Model 2

32.3 (26.6, 38.0)

30.4 (23.4, 37.5)

29.0 (24.6, 33.4)

23.8 (22.0, 25.5)

−3.4

<0.01

 

Model 3

32.1 (26.0, 38.1)

30.7 (24.6, 36.8)

29.0 (23.2, 34.9)

23.3 (20.8, 25.8)

−3.6

<0.01

  1. Cut points for quartiles are: baseline Z-BMI −1.9 to 0.47, −0.46 to 0.27, 0.28 to 0.98, 0.98 to 1.85; Year 3 Z-BMI −2.4 to 0.37, −0.34 to 0.34, 0.35 to 1.14, 1.15 to 2.17; Year 5 visit −2.2 to 0.21, −0.21 to 0.37, 0.38 to 1.09, 1.53 to 2.19; Last visit −2.25 to 0.26, −0.23 to 0.30, 0.33 to 0.98, 0.99 to 2.13
  2. Model 1 Least squares means estimated from linear mixed-effects models including clinic as a random effect and treatment group as a fixed effect
  3. Model 2 Least squares means estimated from linear mixed-effects models including clinic as a random effect and adjusted for treatment group and current adult BMI (continuous, kg/m2) as fixed effects
  4. Model 3 Least squares means estimated from linear mixed-effects models including clinic as a random effect and adjusted for treatment group, current adult BMI (continuous, kg/m2), number of live births, duration of hormone use, age at menarche, race, education, alcohol consumption, smoking status, and family history of breast cancer, as fixed effects (4 missing)
  5. *Test for trend