Table 1 Characteristics of study participants according to NSAID use and menopause status, the Sister Study (2003-2013)

Lifetime use of NSAIDs

< 49 pill-years^a

≥ 49 pill-years^a

< 49 pill-years^a

≥ 49 pill-years^a

No.

50,883

16,311

1960

25,590

6860

 Age, y

55.2 (9.0)

46.4 (5.2)

48.3 (5.0)

59.6 (6.8)

61.5 (6.6)

 BMI, kg/m²

27.8 (6.3)

27.3 (6.3)

29.2 (7.2)

27.7 (6.0)

29.1 (6.7)

 Had alcoholic drinks, days/week

1.5 (2.1)

1.4 (1.9)

1.5 (2.0)

1.6 (2.2)

1.6 (2.3)

 Age at menarche, y

12.6 (1.5)

12.8 (1.5)

12.6 (1.6)

12.6 (1.5)

12.5 (1.5)

 Duration of HRT use, y

3.8 (6.6)

0.4 (1.7)

0.8 (2.8)

5.3 (7.3)

7.2 (8.1)

 Non-Hispanic white

42,558 (83.7)

12,931 (80.1)

16,480 (85.5)

21,490 (84.0)

6190 (90.3)

 Having ≥ college degree

25,886 (50.9)

9090 (55.8)

956 (48.8)

12,505 (48.9)

3244 (47.8)

 Current smokers

4175 (8.2)

1424 (8.7)

254 (13.0)

1974 (7.7)

510 (7.4)

 Nulliparity

9207 (18.1)

3365 (20.6)

478 (21.9)

4240 (16.6)

1143 (16.7)

 Current use of HRT

5276 (10.4)

536 (3.3)

136 (7.0)

3478 (13.7)

1111 (16.3)

 Having ≥ 2 first degree family members with breast cancer

13,275 (27.0)

3544 (21.7)

406 (23.8)

6836 (26.7)

1893 (27.6)

 History of benign proliferative breast disease^b

1842 (3.6)

642 (3.9)

99 (5.1)

827 (3.2)

240 (3.5)

 Prior diagnosis of major medical conditions^c

16,408 (32.3)

4464 (27.4)

920 (46.9)

7837 (30.6)

3129 (45.6)

 Having a mammogram within a year

40,928 (81.4)

12,695 (79.7)

1537 (79.4)

20,857 (82)

5712 (83.6)