Table 1

Baseline characteristics of anti-CCP-positive individuals with non-specific musculoskeletal symptoms and no clinical inflammatory arthritis at baseline (n=136)

CharacteristicNo inflammatory arthritis at baseline (n=136)
AgeYears*51.3 (12.4), 24 to 79
GenderFemale73.7% (100/136)
Symptom durationMonths†
≥12 months
17.2 (7.0, 33.4), 0.2 to 327.7
64.7% (88/136)
Intermittent symptomsPresent17.3% (23/134)
EMSMinutes†
≥30 min
10 (0, 45), 0 to 270
39.0% (53/136)
FDR with RAYes19.8% (26/131)
BMIkg/m2*29.2 (6.6), 17 to 45 (n=98)
SmokerEver71.3% (97/136)
Alcohol consumerNo40.7% (55/136)
No. of painful joints† 5 (2, 9), 0 to 20 (n=126)
Localisation of patient-reported joint symptomsSmall joints only
large joints only
small and large joints
14.3% (18/126)
11.1% (14/126)
65.9% (83/126)
Localisation of patient-reported joint symptoms in extremitiesUpper only
lower only
upper and lower
22.2% (28/126)
8.7% (11/126)
60.3% (76/126)
Symmetry of patient-reported joint symptomsNone reported‡
asymmetrical
symmetrical
13.5% (17/126)
33.0% (36/109)
67.0% (73/109)
No. of tender joints†TJC28
RAI
1 (0, 3), 0 to 21
2 (0, 4), 0 to 16
Localisation of clinical joint tendernessSmall joints only
large joints only
small and large joints
20.6% (28/136)
13.2% (18/136)
27.9% (38/136)
Localisation of clinical joint tenderness in extremitiesUpper only
lower only
upper and lower
22.1% (30/136)
9.6% (13/136)
30.1% (41/136)
Symmetry of clinical joint tendernessNone present‡
asymmetrical
symmetrical
45.6% (62/136)
43.2% (32/74)
56.8% (43/74)
Shared epitopeOne copy
two copies
52.8% (66/126)
19.2% (24/126)
Anti-CCPLow positive
high positive
21.3% (29/136)
78.7% (107/136)
RFLow positive
high positive
15.2% (20/132)
30.3% (40/132)
Autoantibody statusLow positive RF and anti-CCP
high positive RF or anti-CCP
16.9% (23/136)
83.1% (113/136)
hsCRPLevel†
≥2 mg/dL
3.0 (0.8, 9.0), <0.01 to 39.0 (n=119)
56.3% (67/119)
Pain VASmm†
≥50 mm
24 (9, 47), 0 to 100 (n=130)
21.5% (28/130)
  • *Mean (SD), range.

  • †Median (first quartile, third quartile), range.

  • ‡In the joints considered for symmetry (MCPs, PIPs, wrists, elbows, knees, ankles, MTPs). Patient-reported small joint symptoms=symptoms occurring in wrists, hands and/or feet. Clinical small joint tenderness=tender wrists, MCPs, PIPs and/or MTPs. Patient-reported large joint symptoms and clinical large joint tenderness=symptoms or tenderness in the shoulders, elbows, hips, knees and/or ankles. Upper extremity patient-reported symptoms=symptoms in shoulders, elbows, wrists and/or either hands. Upper extremity tenderness=tenderness in shoulders, elbows, wrists, MCPs and/or PIPs. Lower extremity patient-reported symptoms=symptoms in hips, knees, ankles and/or feet. Lower extremity tenderness=tenderness in hips, knees, ankles, mid-tarsal and/or MTP joints.

  • Anti-CCP, anti-cyclic citrullinated peptide; BMI, body mass index; EMS, early morning stiffness; FDR, first degree relative; hsCRP, high sensitivity C reactive protein; MCPs, metacarpophalangeal joints; MTPs, metacarpophalangeal joints; PIPs, proximal interphalangeal joints of the fingers; RA, rheumatoid arthritis; RAI, Ritchie articular index; RF, rheumatoid factor; TJC28, 28 tender joint count; VAS, visual analogue scale.