Table 1 Participant characteristics

Age, median (IQR)

28 (23–36)

31 (26–36)

29 (24–33)

0.23

Female sex, n (%)

97 (100)

59 (100)

37 (100)

-

BMI, mean (± SD)

36.3 (6.1)

37.1 (7.3)

37.0 (6.3)

0.73

Active smoking, n (%)

38 (40)

12 (21)

7 (21)

0.01

Lumbar opening pressure

(cm CSF), median (IQR), [range]

35 (29–44)

[19–66]

22 (19–28)

[13–51]

19 (16–23)

[12–31]

< 0.0001

Papilledema grade^ϒ, n (%)

-

Grade 0

5 (5)

52

37

Grade 1

20 (21)

0

0

Grade 2

33 (34)

0

0

Grade 3

25 (26)

0

0

Grade 4

13 (14)

0

0

Previous headache history, n (%)

52 (54)

36 (69)

13 (35)

< 0.01

Headache, n (%)

89 (92)

52 (100)

34 (92)

0.06

No headache, n (%)

8 (8)

0

3 (8)

Migraine-like headache, n (%)

54 (56)

41 (79)

6 (16)

< 0.0001

Tension type-like headache, n (%)

23 (24)

6 (12)

28 (76)

Unclassifiable/another headache, n (%)

12 (12)

5 (10)

0

Primary headache disorder, n (%)

77 (79)

47 (90)

34 (92)

0.10

Chronic headache^¥, n (%)

55 (57)

40 (77)

0

0.02

Chronic migraine-like headache^¥, n (%)

30 (31)

32 (62)

0

< 0.001

Headache preventive therapy, n

1

3

0

-

Hormonal contraception, n (%)

38 (39%)

24 (46%)

16 (43%)

0.701