Table 2

Repeated biopsy procedures

BaselineRepeat biopsyP valuesP values*Missing (%)
n103103
Months between biopsies†5.37 (5.50)
Biopsy method
 US-NB, n (%)87 (84.5)88 (85.4)
 US-P&F, n (%)11 (10.7)11 (10.7)
 AGSB, n (%)5 (4.9)4 (3.9)0.94
Diagnosis
 RA, n (%)100 (97.1)100 (97.1)
 UA, n (%)1 (1.0)1 (1.0)
 PsA, n (%)2 (1.9)2 (1.9)1.00
Joint biopsied
 Elbow, n (%)2 (1.9)2 (1.9)
 Wrist, n (%)70 (68.0)70 (68.0)
 MCP, n (%)8 (7.8)8 (7.8)
 Knee, n (%)20 (19.4)20 (19.4)
 Ankle, n (%)2 (1.9)2 (1.9)
 MTP, n (%)1 (1.0)1 (1.0)1.000.4
EULAR disease activity
 Remission, n (%)0 (0.0)28 (43.8)
 Low activity, n (%)3 (3.4)4 (6.3)
 Moderate activity, n (%)42 (47.7)21 (32.8)
 High activity, n (%)43 (48.9)11 (17.2)<0.0129.9
Patient-reported outcome measures
 Pre-pain, mean (SD)54.96 (28.01)32.90 (26.01)<0.01<0.012.5
 Post-pain, mean (SD)39.30 (29.29)27.05 (24.12)<0.010.67.5
 Pre-swelling, mean (SD)50.46 (29.56)28.70 (25.32)<0.01<0.015.3
 Post-swelling, mean (SD)34.94 (30.55)20.14 (22.79)<0.01<0.019.5
 Pre-stiffness, mean (SD)57.16 (27.62)31.11 (24.27)<0.01<0.015.3
 Post-stiffness, mean (SD)35.60 (29.55)22.54 (23.84)<0.010.529.3
 Delta pain, mean (SD)−15.23 (29.93)−5.53 (21.13)0.010.627.6
 Delta swelling, mean (SD)−15.04 (31.87)−7.67 (26.41)0.060.709.9
 Delta stiffness, mean (SD)−21.30 (32.70)−7.90 (21.58)<0.010.529.7
Participate in another biopsy?
 Very unlikely, n (%)6 (10.5)5 (8.6)
 Somewhat unlikely, n (%)2 (3.5)3 (5.2)
 Not sure, n (%)8 (14.0)16 (27.6)
 Somewhat likely, n (%)8 (14.0)8 (13.8)
 Very likely, n (%)33 (57.9)26 (44.8)0.250.5150.2
  • *P values adjusted for baseline or follow-up biopsy, disease activity, intra-articular or intramuscular corticosteroid injection during biopsy. P-values on post and delta values were also adjusted for prevalue.

  • †Mean for all in group.

  • EULAR, European League Against Rheumatism; GSB, arthroscopic-guided synovial biopsy; MCP, metacarpophalangeal; MTP, metatarsophalangeal; PsA, psoriatic arthritis; RA, rheumatoid arthritis; UA, undifferentiated arthritis; US-NB, ultrasound-guided needle biopsy; US-P&F, ultrasound-guided portal and forceps.