Table 1

Baseline characteristics of breast cancer cases and controls with BRCA1 and BRCA2 mutations.

Characteristic

BRCA1

BRCA2

Controls

(n = 1,243)

Cases

(n = 1,243)

P

Controls

(n = 422)

Cases

(n = 422)

P


Year of birth, mean (range)

1957.5 (1920-1980)

1957.3 (1920-1980)

0.71

1954.4 (1924-1978)

1955.3 (1924-1978)

0.82

Age at diagnosis, mean (range)

n/a1

0.71

n/a1

n/a1

42.7 (24-67)

n/a1

Country of residence, n (%)

Poland

601 (48%)

matched

0 (0%)

matched

USA

323 (26%)

187 (44%)

Canada

265 (21%)

218 (52%)

Israel

29 (2%)

13 (3%)

Austria

18 (1.5%)

3 (0.7%)

Italy

5 (0.4%)

0 (0%)

United Kingdom

2 (0.2%)

2 (0.5%)

Age at menarche, mean (range)

13.27(8-28)

13.09 (9-21)

0.003

12.64 (8-28)

12.15 (9-17)

0.88

Age at first birth, mean (range)

25.1 (15-44)

24.8 (15-42)

0.08

26.6 (17-44)

26.3 (16-42)

0.37

Age at last birth, mean (range)

29.3 (16-45)

29.0 (17-44)

0.06

30.5 (20-45)

30.2 (18-43)

0.96

Parity2,4, n (%)

1

235 (19%)

65 (15%)

2

663 (53%)

233 (55%)

3

280 (23%)

100 (24%)

≥ 4

65 (5%)

24 (6%)

Mean (range)

2.16 (1-6)

matched

2.20 (1-6)

matched

Breastfeeding, mean months3,4 (range)

10.4 (0-92)

8.8 (0-84)

0.0009

9.7 (0-94)

10.2 (0-86)

0.56

Oral contraceptive use4, ever, n (%)

644 (52%)

657 (53%)

0.95

348 (83.5%)

336 (80.2%)

0.22

Smoking status, ever, n (%)

549 (45%)

574 (46%)

0.74

185 (44.4%)

170 (40.9%)

0.31

Alcohol use, ever, n (%)

832 (67%)

760 (61%)

0.002

305 (73.3%)

284 (68.8%)

0.13

HRT use4, n (%)

148 (12%)

67 (5%)

< 0.0001

69 (16.5%)

45 (10.7%)

0.02

BMI at age 30, mean (range)

22.5 (13-47)

22.6 (9-62)

0.24

22.8 (15-54)

23.0 (12-65)

0.48


1n/a, not applicable. 2Parity includes live births only. 3Breastfeeding is the total months of breastfeeding for each pregnancy combined. 4Parity, breastfeeding, oral contraceptive use and HRT use were censored one year prior to the diagnosis of the matched case for both cases and controls.

Kotsopoulos et al. Breast Cancer Research 2012 14:R42   doi:10.1186/bcr3138

Open Data