Table 1 Baseline characteristics of patients with breast cancer by post-diagnostic use of low-dose aspirin, statins, and metformin, Norway 2004–2017

Age (years) at diagnosis

Median (Q1, Q3)

62.0 (55.0, 68.0)

68.0 (62.0, 75.0)

62.0 (55.0, 69.0)

65.0 (60.0, 72.0)

69.0 (62.0, 77.0)

65.0 (59.0, 72.0)

Education

None/primary school

4977 (23.9%)

1715 (32.2%)

4423 (23.8%)

2269 (29.9%)

108 (34.5%)

540 (36.1%)

Secondary school

10,142 (48.6%)

2644 (49.7%)

8923 (48.0%)

3863 (50.9%)

161 (51.4%)

740 (49.5%)

Higher

5747 (27.5%)

965 (18.1%)

5253 (28.2%)

1459 (19.2%)

44 (14.1%)

215 (14.4%)

Marital status

Not married/partnered

8616 (41.3%)

2420 (45.5%)

7931 (42.6%)

3105 (40.9%)

155 (49.5%)

691 (46.2%)

Married/partnered

12,250 (58.7%)

2904 (54.5%)

10,668 (57.4%)

4486 (59.1%)

158 (50.5%)

804 (53.8%)

Number of children

0

2451 (11.7%)

546 (10.3%)

2204 (11.9%)

793 (10.4%)

46 (14.7%)

179 (12.0%)

1

2931 (14.0%)

785 (14.7%)

2689 (14.5%)

1027 (13.5%)

56 (17.9%)

225 (15.1%)

2

8565 (41.0%)

2038 (38.3%)

7594 (40.8%)

3009 (39.6%)

89 (28.4%)

528 (35.3%)

 ≥ 3

6919 (33.2%)

1955 (36.7%)

6112 (32.9%)

2762 (36.4%)

122 (39.0%)

563 (37.7%)

Country of origin

Norway

18,979 (91.0%)

4969 (93.3%)

16,893 (90.8%)

7055 (92.9%)

279 (89.1%)

1312 (87.8%)

Other Nordic countries^a

598 (2.9%)

136 (2.6%)

554 (3.0%)

180 (2.4%)

7 (2.2%)

39 (2.6%)

Rest of the world

1289 (6.2%)

219 (4.1%)

1152 (6.2%)

356 (4.7%)

27 (8.6%)

144 (9.6%)

Stage

Local

12,859 (61.6%)

3319 (62.3%)

11,331 (60.9%)

4847 (63.9%)

151 (48.2%)

888 (59.4%)

Regional

6296 (30.2%)

1621 (30.4%)

5642 (30.3%)

2275 (30.0%)

127 (40.6%)

497 (33.2%)

Distant

553 (2.7%)

95 (1.8%)

542 (2.9%)

106 (1.4%)

12 (3.8%)

33 (2.2%)

Missing

1158 (5.5%)

289 (5.4%)

1084 (5.8%)

363 (4.8%)

23 (7.3%)

77 (5.2%)

Molecular subtype

Luminal A

4600 (22.0%)

1053 (19.8%)

4029 (21.7%)

1624 (21.4%)

45 (14.4%)

275 (18.4%)

Luminal B HER2-

9081 (43.5%)

2189 (41.1%)

8057 (43.3%)

3213 (42.3%)

138 (44.1%)

681 (45.6%)

Luminal B HER2 + 

1689 (8.1%)

360 (6.8%)

1511 (8.1%)

538 (7.1%)

22 (7.0%)

108 (7.2%)

HER2 + 

777 (3.7%)

170 (3.2%)

707 (3.8%)

240 (3.2%)

10 (3.2%)

44 (2.9%)

TNBC

1420 (6.8%)

335 (6.3%)

1273 (6.8%)

482 (6.3%)

21 (6.7%)

97 (6.5%)

Missing

3299 (15.8%)

1217 (22.9%)

3022 (16.2%)

1494 (19.7%)

77 (24.6%)

290 (19.4%)

Histology

Ductal carcinoma

16,482 (79.0%)

4174 (78.4%)

14,674 (78.9%)

5982 (78.8%)

255 (81.5%)

1214 (81.2%)

Lobular carcinoma

2667 (12.8%)

664 (12.5%)

2379 (12.8%)

952 (12.5%)

38 (12.1%)

162 (10.8%)

Other carcinoma

1717 (8.2%)

486 (9.1%)

1546 (8.3%)

657 (8.7%)

20 (6.4%)

119 (8.0%)

Concomitant medications

Low-dose aspirin

–

–

1849 (9.9%)

3475 (45.8%)

145 (46.3%)

634 (42.4%)

Other antiplatelets

185 (0.9%)

411 (7.7%)

93 (0.5%)

503 (6.6%)

25 (8.0%)

61 (4.1%)

Statins

4116 (19.7%)

3475 (65.3%)

–

–

196 (62.6%)

973 (65.1%)

Metformin

861 (4.1%)

634 (11.9%)

522 (2.8%)

973 (12.8%)

–

–

Non-metformin antidiabetics

370 (1.8%)

363 (6.8%)

238 (1.3%)

495 (6.5%)

–

–

NSAIDs

3111 (14.9%)

972 (18.3%)

2650 (14.2%)

1433 (18.9%)

32 (10.2%)

301 (20.1%)

Beta-blockers

2611 (12.5%)

2023 (38.0%)

2142 (11.5%)

2492 (32.8%)

114 (36.4%)

555 (37.1%)

ACE-inhibitors

1360 (6.5%)

972 (18.3%)

1082 (5.8%)

1250 (16.5%)

87 (27.8%)

297 (19.9%)

ARB

4612 (22.1%)

2307 (43.3%)

3789 (20.4%)

3130 (41.2%)

129 (41.2%)

758 (50.7%)

CCB

2782 (13.3%)

1749 (32.9%)

2319 (12.5%)

2212 (29.1%)

127 (40.6%)

556 (37.2%)

Diuretics

4259 (20.4%)

2448 (46.0%)

3591 (19.3%)

3116 (41.0%)

166 (53.0%)

756 (50.6%)