Table 1

Reproductive history among LN cases and lupus cases without nephritis stratified by current age (females only)

Ages 18 to 34 (n = 127)

Age at menarche

All LN cases (n = 64)

Lupus cases without nephritis (n = 63)

OR (95% CI)

8 to 9

5 (8)

3

1.84 (0.35 to 9.62)

10

3

7 (11)

0.54 (0.11 to 2.65)

11

5 (8)

8 (13)

0.58 (0.15 to 2.29)

12

11 (17)

18 (29)

0.76 (0.27 to 2.18)

13

18 (28)

19 (30)

1.00 (referent)

14

7 (11)

4

1.54 (0.34 to 6.93)

15

9 (14)

2

4.94 (0.88 to 27.92)

16

5 (8)

2

3.57 (0.56 to 22.73)

17 to 18

1

0

-

Trend test (P value)

(0.03)

Missing value (refused) for one lupus nephritis case; three lupus nephritis cases excluded because diagnosis occurred 3 to 4 years before menarche (at age 14); total n = 78.

Dooley et al. Arthritis Research & Therapy 2012 14(Suppl 3):A23   doi:10.1186/ar3957