Table 1.

Study population characteristics

	Cases (n = 68)	Controls (n = 68)	P-value††
Age at enrollment (years)
Mean (SD)	60.2 (5.6)	60.3 (5.7)	0.966
BMI
Mean (SD)	26.6 (3.1)	26.3 (3.6)	0.603
Missing	1	-
Use of oral contraceptives, n (%)
No, but used to in the past	36 (52.9)	40 (58.8)	0.490
No, never	32 (47.1)	28 (41.2)
Duration of oral contraceptives use* (years)
Median (IQR)	10.0 (4.3-15.8)	4.5 (2.0-10.0)	0.018
Use of HT, n (%)
No, but used to in the past	7 (10.3)	6 (8.8)	0.771
No, never	61 (89.7)	62 (91.2)
Duration of HT use* (years)
Median (IQR)	1.0 (1.0-8.0)	2.0 (1.0-10.0)	0.273
Ovariectomy, n (%)
Both ovaries removed	5 (7.4)	3 (4.5)	0.479
Missing	-	1
Parity, n (%)
Nulliparous	10 (14.7)	5 (7.4)	0.171
Number of children†
Median (IQR)	2.0 (2.0-3.0)	3.0 (2.0-3.0)	0.100
Smoking, n (%)
No, but used to in the past	31 (45.6)	34 (50.0)	0.607
No, never	37 (54.4)	34 (50.0)
Pack-years smoking until stop date‡
Median (IQR)	7.9 (1.9-16.4)	4.1 (1.4-10.2)	0.187
Missing	1	3
Alcohol intake (g/day)§
Median (IQR)	2.0 (0.2-7.2)	2.5 (0.2-8.4)	0.638
Use of medicines, minerals or vitamins#, n (%)
Yes	46 (67.6)	44 (64.7)
No	22 (32.4)	24 (35.3)	0.717
Time since last meal and/or drink** (min)
Median (IQR)	108 (87-137)	116 (88-137)	0.651

SD: standard deviation; BMI: body mass index; IQR: inter-quartile range; HT: menopausal hormone therapy; * Among former oral contraceptives/HT users; ^† Among women with children; ^‡ Among former smokers; ^§ Energy-adjusted alcohol intake at enrollment; ^# In last week before blood collection; ** At moment of blood collection; ^†† Independent samples T test for age and BMI, Mann-Whitney U test for other continuous variables, and Pearson Chi-Square test for categorical variables.