Table 3

Association of allergic conditions with RF positive RA among the EIRA cases from 1995 to 2016

Allergic conditionN (%) or median (IQR)
RF +RA cases (N=2301)Controls (N=5429)Adjusted* OR (95% CI) for RF +RA
Animal dander62 (7)134 (5)1.47 (1.06 to 2.03)
Allergic rhinitis180 (9)387 (8)1.35 (0.99 to 1.84)†
Atopic dermatitis227 (11)453 (10)1.04 (0.87 to 1.23)
Metal allergy28 (3)58 (2)1.25 (0.78 to 2.00)
Respiratory allergy106 (11)271 (9)1.18 (0.92 to 1.51)
Food allergy12 (1.3)40 (1.5)1.00 (0.52 to 1.95)
Plants and pollen90 (10)293 (10)1.03 (0.79 to 1.33)
Allergy to chemicals15 (2)51 (1.9)0.83 (0.46 to 1.51)
  • *Adjusting for age, sex, residential area, body mass index, education and smoking. Bold values are statistically significant (p<0.05).

  • †Interaction term with smoking was significant (p<0.05). OR shown assumes most common scenario (never smoker).

  • EIRA, Epidemiological Investigation of Rheumatoid Arthritis; RA, rheumatoid arthritis; RF, rheumatoid factor.