Research Article

Increased IL-33 in Synovial Fluid and Paired Serum Is Associated with Disease Activity and Autoantibodies in Rheumatoid Arthritis

Table 2

Correlation analysis between SF-serum IL-33 (pg/mL) and clinical and laboratory variables.

MeasurementsSF IL-33 ( )Serum IL-33 ( )
r P r P

Age (yrs)−0.1060.257−0.0140.921
Tender joint count, 0–46 joints0.0950.3470.3270.020 *
Swollen joint count, 0–48 joints0.1920.0560.1340.354
DAS28-ESR0.2090.047 * 0.2530.102
ESR (mm/h)0.2560.008 * 0.2130.150
CRP (mg/L)0.1660.0730.2190.116
C3 (g/L)0.1130.2600.2670.061
C4 (g/L)0.0390.6980.1800.211
IgA (g/L)0.2460.012 * 0.1070.457
IgG (g/L)0.3090.001 * 0.1360.343
IgM (g/L)0.3010.002 * 0.2200.121
RF-IgM (U/mL)0.327<0.001 * 0.3420.011 *
RF-IgG (IU/mL)0.2140.037 * 0.1830.208
GPI (mg/L)0.3640.001 * 0.5050.000 *
Anti-CCP (RU/mL)0.1040.2840.0520.716

P < 0.05. Spearman's correlation test was used.