No reliable variables to predict clinical or laboratory response to treatment in patients with rheumatoid arthritis were available until recently.
To asses the potential predictive value of the Sharp's modified radiographic joint damage index for the assessment of clinical and laboratory response to a methylprednisolone i.v. pulse.
Twenty-two patients suffering from rheumatoid arthritis received a single i.v. pulse of 1 g of methylprednisolone. Hand X-rays were taken at baseline and blindly scored by two trained radiologists. Clinical and laboratory variables were assessed at baseline and at weekly intervals up to 30 days plus a 60 days final evaluation. Improvement was defined as a 50% amelioration in 4 variables.
Assessment of radiographic scores had a high correlation between and within observers (intraclass correlation = 0.998). Sharp score did not reach statistical significance as global predictor for the inflammatory variable response to methylprednisolone. However, when the number of swollen joints was taken into account, patients with a low erosive score (Sharp < or = 50) had a more prolonged clinical response, than patients with higher erosive score (Sharp > 50) (Fisher test p = 0.023). It is of clinical importance to point out that among patients with high Sharp score there were also responders who reached a high level of improvement. A statistically significant correlation between the basal PCR serum titers and the radiographic score (p < 0.02) was observed.
The number of swollen joints and other variables that consider joint structural changes should be considered for the assessment of rheumatoid arthritis patients.