Cases (n = 52)

Controls (n = 53)

p-value

RA duration (years)

2.5 ± 1.1

3.0 ± 1.2

0.01

Age of onset (years)

1.5 ± 1.7

2.8 ± 1.9

0.7

Morning stiffness

1.7 ± 2.0

3.2 ± 2.0

0.3

<30 min

1.3 ± 1.8

2.8 ± 1.9

0.8

≥30 min

2.5 ± 1.7

3.7 ± 1.7

0.1

Ankylosed joints

1.7 ± 2.1

3.0 ± 1.9

0.3

Tender joints

11.3 ± 9.4

18.5 ± 9.7

0.0006

Swollen joints