To develop inflammatory activity index (IAI) for assessment of rheumatoid arthritis (RA) activity in wide clinical practice.
Leflunomide was given to 414 patients for 18.4 +/- 5.7 weeks, on the average. The assessment of the drug efficacy was made by arthralgia severity according to visual analog scale (VAS), duration of morning stiffness, the number of painful joints at palpation, number of swollen joints (NSJ), general condition (GC) of the patient, ESR. DAS28 was used as a basic indicator of the disease activity and efficacy. IAI was formed on the basis of DAS28 and 3 baseline components--NSJ (28 joints), GC and ESR.
DAS28 and IAI significantly correlated (r = 0.87, p < 0.01). Comparison of pairs of these indices can specify ranges of IAI corresponding to high, moderate and low RA activity in assessment by DAS28.
IAI is a simple and reliable index of RA activity in clinical practice.