Height, adiposity and body fat distribution and breast density in young women

Breast Cancer Research

Table 3 Percentage dense breast volume differences associated with difference in anthropometric and body composition measures

	Unadjusted^a				Adjusted^b				Also adjusted for childhood or young adult BMI^c
	% Diff	95% CI	Pvalue	R ^2d	% Diff	95% CI	Pvalue	R ²	% Diff	95% CI	Pvalue	R ²
Adult anthropometric measures
Height (cm)	3.7	-13.8, 24.8	0.70	< 0.01	21.0	9.4, 33.8	< 0.001	0.55	18.7	6.7, 32.1	0.002	0.57
BMI (kg/m²)	-50.2	-55.0, -44.8	< 0.001	0.49	-50.2	-55.4, -44.4	< 0.001	0.54	-45.1	-51.5, -37.8	< 0.001	0.56
Waist (cm)	-51.9	-58.8, -43.8	< 0.001	0.38	-51.5	-59.7, -41.6	< 0.001	0.47	-44.4	-51.0, -37.0	< 0.001	0.56
Adult DXA measures
Total fat (%)	-50.8	-55.0, -46.4	< 0.001	0.53	-50.1	-55.0, -44.7	< 0.001	0.55	-44.4	-49.6, -38.7	< 0.001	0.60
A:G ratio	-52.3	-55.6, -48.8	< 0.001	0.57	-52.0	-54.5, -49.5	< 0.001	0.60	-47.0	-48.5, -45.4	< 0.001	0.67
Childhood BMI
BMI z-score at 8 to 10 years old	-40.0	-47.0, -32.0	< 0.001	0.22	-41.7	-47.5, -35.2	< 0.001	0.34	-17.3	-22.4, -11.9	< 0.001	0.56

Percentage differences (%Diff) in percentage dense breast volume associated with a one-standard-deviation difference in anthropometric and dual-energy X-ray absorptiometry (DXA) body composition measures. Results are also interpretable as the excess relative ratio. To convert to the relative ratio (RRatio), use the formula: RRatio = (%Diff + 100)/100. A:G ratio, android:gynoid fat ratio; BMI, body mass index; CI, confidence interval. ^aEstimates from six linear mixed-effects models including clinic as a random effect and anthropometric and body composition variables as fixed effects. Anthropometric and body composition variables are modeled separately without mutual adjustment. ^bEstimates from six linear mixed-effects models as described for unadjusted plus including race, education (attended college), smoking status, duration of hormone use, and parity as fixed effects. Model for height also includes weight as a fixed effect. ^cEstimates from six linear mixed-effects models as described for adjusted plus including BMI z-score at 8 to 10 years old as a fixed effect in adult anthropometric and DXA models and young adult BMI in the childhood BMI model. ^dProportion of variance explained by model.