Background rheumatoid arthritis (RA) is a chronic inflammatory disease that can lead to join destruction, deformity and loss of function. The measurement of the disease activity is very important in the patient's follow-up. In RA there are several composite indices for assess this parameter; the DAS 28-ESR and the CDAI are qualified by the physician and the Rheumatoid arthritis disease activity index (RADAI) is qualified by the patient. It is unknown which of the two approaches is most appropriate.
Objectives To compare the measurement of the activity of the RA from the perspective of the physician and the patient through RADAI and DAS 28-ESR.
Methods Population: patients with RA who participated in an open label clinical study with the use of methotrexate and anti-TNF alpha.
Subjects and methods: demographic, clinical, and treatment data were obtained. DAS28-ESR, CDAI, RADAI, HAQ-DI, EuroQoL 5D were assessed every 4 weeks for 6 months.
Results We included 190 patients, 179 (94.2%) were women, mean age 43.9±11.9 years, educational level of 8.9±3.9 years. The RADAI had a high internal consistency (Cronbach's alpha =0.89). The baseline score was 6.04±1.6 and at six months of 2.52±1.7. The baseline score of DAS28-ESR was 5.36±0.74 and at six months of 2.95±0.89. The baseline score of CDAI was 28.05±8.5 and at six months of 7.01±5.3. The HAQ baseline was 1.49±0.64 and at six months of 0.70±0.63 and EuroQoL baseline was of 0.4156±0.20 and at six months of 0.6733±0.17 (p=0.000 for all comparisons) There was moderate to good correlations of RADAI with the DAS28, CDAI, HAQ-DI and EuroQoL5D. The three indexes had a good ability to discriminate between groups of patients for degree of activity. In the final assessment had activity of RA by DAS28-ESR in 31.6%, by CDAI in 26.3% and by RADAI in 35.8% of the patients. The area under the curve of the CDAI was 0.88, the DAS28-ESR of 0.72 and 0.71 of the RADAI with similar sensitivity and specificity.
Conclusions a comparison of activity from the perspective of the patient and the doctor are equivalent with the use of specific indexes. DAS28-ESR, RADAI, and CDAI are a valid measure of disease activity.
Disclosure of Interest None declared