Table 3

Baseline demographic, clinical and serological characteristics of the 192 patients subdivided according to diagnosis after 24 months

Parameter at onset

Patients developing RA

Patients not developing RA

P

Number

%

Number

%

Patients

72

37.5

120

62.5

Age, years, mean ± SD

52 ± 16

na

52 ± 15

na

0.895

Female

57

79.2

90

75.0

0.628

Monoarthritis

7

9.7

11

9.2

0.999

Oligoarthritis

16

22.2

41

34.2

0.111

Polyarthritis

49

68.1

68

56.6

0.158

Hand joints arthritis

55

76.4

71

59.2

0.023

CRP+

41

56.9

58

48.3

0.314

CRP ratio, median (IR)

1.9 (0.6-1.9)

0.9 (0.6-2.6)

0.031

ESR increase

38

52.8

65

54.2

0.970

ESR median (IR)

24 (12.3-53.3)

22.5 (16.0-38)

0.773

RF+

45

62.5

34

28.3

< 0.0001

RF ratio, median (IR)

2.3 (0.6-7.8)

0.6 (0.5-1.2)

< 0.0001

RF low+/total RF+

11

24.4

15

44.1

0.109

RF high+/total RF+

34

75.5

19

55.9

ACPA+

53

73.6

27

22.5

< 0.0001

ACPA ratio, median (IR)

5 (0.6-14.3)

0.5 (0.3-0.8)

< 0.0001

ACPA low+/total+

7

13.2

6

22.2

0.476

ACPA high+/total+

46

86.8

21

77.8

RF+/ACPA-

2

2.8

12

10

0.115

RF-/ACPA+

10

13.9

5

4.2

0.031

RF+/ACPA+

43

59.7

21

18.3

< 0.0001

RF-/ACPA-

17

23.6

81

67.5

< 0.0001

RA, rheumatoid arthritis; CRP, C-reactive protein; IR, interquartile range; ESR, erythrocyte sedimentation rate; RF, rheumatoid factor; ACPA, anti-citrullinated peptide antibodies; NA, not applicable.

Bizzaro et al. Arthritis Research & Therapy 2013 15:R16   doi:10.1186/ar4148