Table 2. Associations between alcohol consumption and volumetric mammographic density among all women.

			β (95% Confidence interval)
			Absolute dense volume (cm3)		Per cent dense volume (%)
Alcohol consumption (g per day)	N	%	Unadjusted	Multivariable adjusteda	Unadjusted	Multivariable adjusteda
0	9728	18.3	Ref.	Ref.	Ref.	Ref.
0.1–4.9	13 437	25.3	−0.6 (−1.5, 0.3)	−0.2 (−0.8, 1.1)	1.0 (0.9, 1.2)	0.3 (0.2, 0.4)
5.0–9.9	19 659	37.1	−1.6 (−2.4, −0.8)	0.5 (−0.4, 1.4)	1.2 (1.0, 1.3)	0.3 (0.2, 0.4)
10.0–19.9	3538	6.7	−0.8 (−2.1, 0.5)	0.9 (−0.5, 2.2)	1.0 (0.8, 1.2)	0.4 (0.3, 0.6)
20.0–29.9	5635	10.6	−1.7 (−2.8, −0.6)	1.3 (0.2, 2.5)	0.5 (0.3, 0.6)	0.2 (0, 0.3)
30.0–40.0	1063	2.0	1.6 (−0.5, 3.7)	4.5 (2.2, 6.8)	0.3 (0, 0.6)	0.5 (0.2, 0.8)
Pglobalb			<0.001	<0.001	<0.001	<0.001
For every 10 g per day increasec			−0.2 (−0.5, 0.2)	0.9 (0.5, 1.3)	0 (0, 0.1)	0.1 (0.02, 0.1)
Ptrendd			0.34	<0.001	0.86	0.01

Abbreviations: β=regression coefficient; CI=confidence interval.

^aRegression coefficients were adjusted for age at mammography (5-year categories), body mass index (<25.0, 25.0–29.9, and ⩾30.0 kg m⁻²), family history of breast cancer in mother or sisters (yes, no), age at menarche (<13, 13, 14, and ⩾15 years), parity and age at first birth (nulliparous; 1–2 births, age at first birth<26 years; 1–2 births, age at first birth ⩾26 years, ⩾3 birth; age at first birth <26 years; ⩾3 births, age at first birth ⩾26 years), oral contraceptives use (never, ever), menopausal status (pre/postmenopausal), hormone replacement therapy use (never, past, current), education level (secondary school, high school, university or higher, other), smoking status (never, past, current), physical activity (<40.0, 40.0–44.9, 45.0–49.9, and ⩾50.0 metabolic equivalent hours per day), and ethnicity (having a European ancestry; yes or no).

^bP_global values were obtained from regression models using alcohol consumption as a categorical exposure.

^cChange in absolute dense volume for every 10 g per day increase in alcohol consumption, from regression models with alcohol consumption as a continuous exposure.

^dP_trend values were obtained from regression models using alcohol consumption as a continuous exposure.