OSTEOCALCIN IN PATIENTS WITH RHEUMATOID-ARTHRITIS - A ONE-YEAR FOLLOW-UP-STUDY

Objective. To analyze clinical, radiological, and drug (disease modify ing antirheumatic drug, DMARD) dependent factors influencing bone turn over in patients with rheumatoid arthritis (RA). Methods. We investiga ted in a one-year double blind randomized study comparing intramuscula r (im) gold with im methotrexate (MTX), whether the variation of infla mmatory activity or functional capacity, the ascending anatomic stage, or DMARD treatments have an influence on bone formation (osteocalcin) in patients with RA. Results. Patients (n = 48) enrolled at the begin ning of our study had significantly increased osteocalcin levels (3.45 +/- 0.93 --> 4.42 +/- 1.39 ng/ml p < 0.02) after one year if inflamma tory activity decreased (greater than or equal to 1 SD: erythrocyte se dimentation rate (ESR) 26.4 mm/h, C-reactive protein (CRP) 3.8 mg/dl). We found a significant negative correlation of the one-year CRP-(r = -0.44, p < 0.001) or ESR differences (r = -0.45, p < 0.001) with the c orresponding osteocalcin differences. This was also evident if these p atients were pooled with 15 patients excluded from the double blind st udy as already receiving DMARD treatment (n = 63; p < 0.01). Patients with impaired functional capacity also had significantly reduced osteo calcin levels (p < 0.01). In both cases, alkaline phosphatase showed n o significant differences. Conclusions. Our data suggest that osteocal cin, a useful followup variable of bone turnover, is changed significa ntly (p < 0.02) in patients with RA regarding inflammatory activity an d functional capacity. In contrast to alkaline phosphatase, a fall in inflammatory activity stimulated and impairment of functional capacity significantly decreased osteocalcin levels in patients with RA.