Improvement of the HAQ score by infliximab treatment in patients with RA: its association with disease activity and joint destruction

Abstract

We conducted a two-year prospective study to clarify the efficacy of infliximab at improving the health assessment questionnaire (HAQ) score and associated factors in 67 patients with advanced rheumatoid arthritis (RA). All patients were scheduled to receive infliximab at a dose of 3 mg/kg at weeks 0, 2, 6 and every eight weeks thereafter through to week 102, and were fully examined at the time of each infusion. Parameters of disease activity such as the serum level of C-reactive protein (CRP), the serum level of matrix metalloproteinase-3 (MMP-3) and the 28-joint disease activity score (DAS28) were obtained, and the functional capabilities of the patients were assessed using the HAQ score. The serum CRP, the MMP-3, the DAS28(CRP) level, and the mean HAQ score decreased rapidly at two weeks after the start of infliximab treatment (CRP from 3.7 to 0.9 mg/dl, MMP-3 from 362.3 to 192.8 ng/ml, DAS28(CRP) from 5.6 to 3.7, and HAQ score from 1.5 to 0.9). Compared with the baseline values, the mean progression of the modified van der Heijde (vdH)–Sharp score after one year was 4.4 ± 5.8 (median: 3.0), and that after two years was 3.1 ± 6.9 (median: 1.0). A 93% reduction in the rate of joint destruction, as measured using the vdH–Sharp score, was estimated after infliximab therapy. Patients with less joint damage (shorter disease duration or lower vdH–Sharp score) regained more of their daily activities. The present study demonstrated the importance of activity control before the progression of irreversible factors, such as joint destruction, for maintaining the functional capacities of RA patients.