Table 1

Characteristics of patients from DESIR cohort according to presence or not of MRI inflammatory lesions

Inflammatory MRI
OverallThoracicLumbarSacroiliac
N=648Abnormal n=125Normal n=523p*Abnormal n=140Normal n=508p*Abnormal n=303Normal n=345p*
Gender (women)338 (53)39 (31.5)299 (58.1)<0.000155 (3.,3)286 (56.9)<0.0001132 (44.2)209 (61)<0.0001
Age (years)33.8 (8.7)34.4 (8.5)33.6 (8.7)0.3535.4 (8.5)33.4 (8.7)0.0132.5350.0003
HLA B27 status374 (58.2)92 (74)54.6 (282)<0.000189 (63.5)287 (5.7)0.15207 (68.1)169 (49)<0.0001
BMI (m/kg²)23.9 (4.6)24.7 (6.9)23.7 (3.8)0.0424.2 (6.5)23.8 (3.9)0.3423.923.90.91
DMARD†57 (8.8)9 (7.1)48 (9.3)0.2111 (7.6)46 (9.1)0.5124 (7.7)33 (9.7)0.49
NSAID intake† (Y/N)597 (92.8)117 (93.6)480 (92.7)0.72131 (93.6)471 (9.7)0.73288 (95.1)314 (91)0.05
NSAID intake† (% of daily intake)4.3 (14.7–78.3)44.8 (17.4–71.4)40.4 (15–78.8)0.9737.6 (14.6–71.3)43.7 (15.7–79.8)0.4248.2 (19.1–80.5)38 (13.3–76.4)0.04
CRP3.1 (1–7.1)5 (1.6–13)3 (1–6)<0.00014 (1–10.5)3 (1–6.1)<0.00014 (1.5–9.6)2.5 (1–5)<0.0001
Thoracic pain393 (61.5)86 (68)307 (59.7)0.0687 (63)310 (61.3)0.7176 (58.7)221 (64.2)0.14
Lumbar pain589 (91.7)113 (90.4)476 (92.1)0.54134 (95.7)460 (90.7)0.06275 (91.1)319 (9.5)0.51
Buttock pain513 (79.6)96 (76.8)412 (80.2)0.4105 (76.6)408 (80.5)0.32257 (85.7)256 (74.4)0.0001
  • BMI, Body Mass Index; CRP, C-reactive protein; DMARD, Disease Modifying AntiRheumatic Drug; ; NSAID, Non-Steroidal Anti-inflammatory Drugs; SIJ, Sacro-Iliac Joints.

  • Categorical variables were expressed as percentage (%), continuous variables as mean and SD except for CRP as median (25–75) interquartile space.

  • *Continuous variables were compared using student t-test or Wilcoxon-Mann-Whitney as appropriate, categorical variables using Pearson χ2 test.

  • †Regarding treatments, comparisons were systematically adjusted for propensity score using logistic regression models.

  • Hs-CRP was log-transformed for statistical test.