Table 1

Comparing demographic, clinical, biochemical and imaging features between participants with and without identifiable ADC lesions

With identifiable ADC lesionsWithout identifiable ADC lesionsP value
Age (N=301) (years)45.7±13.142.7±13.10.09
Male gender (N=301)55 (67.1%)115 (52.5%)0.02
Duration of back pain (N=299) (years)13.4±10.711.2±11.20.13
HLA-B27 positivity (N=290)69 (85.2%)164 (78.5%)0.20
History of inflammatory bowel disease (N=298)3 (3.8%)5 (2.3%)0.49
History of psoriasis (N=298)8 (10.0%)36 (16.5%)0.16
Family history of SpA (N=286)15 (19.5%)48 (23.0%)0.53
Radiographical axial SpA (N=294)5 (71.4%)21 (52.5%)0.35
Fulfilled ASAS axial SpA criteria (N=300)79 (97.5%)200 (91.3%)0.06
Back pain NRS (N=294)5.8±2.45.6±2.40.50
Ever peripheral arthritis (N=298)36 (45.0%)132 (60.6%)0.02
Tender joint count (N=292)0.8±1.51.6±3.10.02
Swollen joint count (N=293)0.3±0.90.7±1.60.02
Ever enthesitis (N=297)35 (43.8%)97 (44.7%)0.88
CRP (N=300) (mg/dL)1.2±1.41.0±1.90.48
ESR (N=299) (mm/hour)37.1±23.330.1±24.90.03
ASDAS-CRP (N=292)2.1±0.82.0±0.90.44
ASDAS-ESR (N=291)3.3±1.03.1±1.10.11
ADC background (N=82) (mm2/s)
ADCmax (N=82) (mm2/s)1.45±0.31×10−3
ADCmean (N=82) (mm2/s)0.77±0.19×10−3
nADCmax (N=82)6.5±2.1
nADCmean (N=82)3.4±1.0
SPARCC SI MRI score (N=297)3.4±5.93.1±6.10.68
SPARCC spine MRI score (N=294)13.7±10.23.5±6.0<0.001
  • ADC, apparent diffusion coefficient; ADCmax, maximum apparent diffusion coefficient; ADCmean, mean apparent diffusion coefficient; ASAS, Assessment of Spondyloarthritis International Society; CRP, C reactive protein; ESR, erythrocyte sedimentation rate; HLA, human leucocyte antigen; N, number; nADCmax, normalised maximum apparent diffusion coefficient; nADCmean, normalised mean apparent diffusion coefficient; NRS, Numerical Rating Score; SPARCC, Spondyloarthritis Research Consortium of Canada; SpA, spondyloarthritis.