Table 2

Results of univariable Cox regression analyses of baseline clinical and serological factors in relation to arthritis development

HR (95% CI)p Value
Age, per year1.004 (0.98 to 1.03)0.78
Female1.02 (0.45 to 2.29)0.96
Family history positive for RA1.37 (0.66 to 2.85)0.39
Symptom duration per week (n=141)0.99 (0.98 to 1.01)0.32
Gradual symptom onset (n=148)0.68 (0.30 to 1.53)0.35
Localisation of initial symptoms (n=148)
 Small joints onlyRefRef
 Large joints only1.89 (0.44 to 8.14)0.39
 Small and large joints5.28 (2.38 to 11.73)<0.001
Localisation of initial symptoms
 Upper extremitiesRefRef
 Lower extremities1.36 (0.40 to 4.58)0.62
 Upper and lower extremities1.47 (0.62 to 3.47)0.38
Symmetrical localisation of initial symptoms (n=148)0.59 (0.28 to 1.23)0.16
Morning stiffness ≥60 min (n=143)1.89 (0.92 to 3.87)0.081
68-TJC (n=145)0.98 (0.93 to 1.04)0.47
BMI, per kg/m2 (n=147)1.01 (0.94 to 1.08)0.80
Present smoker1.28 (0.59 to 2.79)0.54
CRP, per mg/L1.06 (1.03 to 1.09)<0.001
RF-positive6.94 (3.34 to 14.43)<0.001
ACPA-positive10.07 (4.87 to 20.82)<0.001
  • Presented are the HRs of univariable analyses including 149 patients with clinically suspect arthralgia of which 30 developed clinical arthritis. When data on clinical characteristics were missing, the number of patients with available data is presented in the first column.

  • ACPA, anticitrullinated peptide antibodies; BMI, body mass index; CRP, C reactive protein; RA, rheumatoid arthritis; ref, reference; RF, rheumatoid factor; TJC, tender joint count.