Table 6

Characteristics of the sensory symptom clusters

CategoryCluster 1
n=16
Cluster 2
n=20
Cluster 3
n=22
Cluster 4
n=20
P value
WPI2.7±1.93.1±2.23.5±2.81±1.20.03
PD8.6±2.96±3.98.8±5.60.7±1.9<0.001
Female sex9 (56.2%)5 (25%)9 (40.9%)2 (10%)0.02
Age (years)37.4±8.543.5±11.743.1±10.236.2±9.40.58
BMI (kg/m²)26.9±5.726.3±427±4.924.7±4.50.24
HLA-B27 positivity15 (93.8%)20 (100%)19 (86.4%)18 (90%)0.4
Symptom duration (years)14.3±9.220.1±12.916.5±9.510.7±7.60.14
ASDAS at follow-up2.1±0.81.8±0.81.8±0.71.1±0.5<0.001
CRP at baseline (mg/l)8.4±6.419.9±19.211.7±13.413.1±17.10.87
CRP at follow-up (mg/l)4.4±5.14.6±5.73.4±3.82.6±2.80.14
Current NSAID intake6 (37.5%)6 (30%)14 (63.6%)4 (20%)0.03
  • Continuous variables are expressed as mean±SD and categorial variables as n (%). P values were calculated using χ2 for categorial variables and Analysis of Variance for continous variables.

  • ASDAS, Ankylosing Spondylitis Disease Activity Score; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BMI, body mass index; CRP, C reactive protein; HLA, human leucocyte antigen; NSAID, non-steroidal anti-inflammatory drugs; PD, PainDETECT; WPI, Widespread Pain Index.