Table 1

Baseline demographic, clinical and serological characteristics of the 192 patients with undifferentiated arthritis

Characteristics

Baseline values

Percent patients

Age, years, mean ± SD

52 ± 16

na

Female, n

147

76.6

Monoarthritis, n

18

9.4

Oligoarthritis, n

57

29.7

Polyarthritis, n

117

60.9

Arthritis of hand joints, n

126

65.6

CRP

Positive, n

98

51.0

Ratio, median (IR)

1.1 (0.6-4.1)

na

ESR

Increased, n

103

53.6

Ratio, median (IR)

22.5 (14-40)

na

Rheumatoid factor

Positive

79

(41.4)

Ratio, median (IR)

0.7 (0.5-3.9)

na

Low titer on total positive

26

(32.9)

High titer on total positive

53

(67.1)

ACPA

Positive, n

80

(41.7)

Ratio, median (IR)

0.5 (0.3-7.8)

na

Low levels on total positive, n

13

(16.2)

High levels on total positive, n

67

(83.8)

Baseline therapy

None, n

88

(45.8)

NSAIDs/Coxibs, n

66

(34.4)

Corticosteroids, n

10

(5.2)

n, number of patients; CRP, C-reactive protein; IR, interquartile range; ESR, erythrocyte sedimentation rate; ACPA, anti-citrullinated peptide antibodies; NSAID, non-steroidal anti-inflammatory drug; Coxib, Cox-2 selective inhibitor; na, not applicable.

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