Copper levels in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, autoimmune-based disease of the connective tissue with still unknown etiology. Numerous studies have indicated the association between Copper (Cu) and ceruloplasmin (Cp) concentrations and pathogenesis of RA.

To compare the concentrations of Cu and Cp in different biological samples and their correlation with the inflammatory process, between a group of patients with RA and a control group of healthy individuals.

The study enrolled 74 Caucasian patients (20 men and 54 women), aged 29-50 (mean age 39.8±6.1 years) diagnosed with RA. The control group consisted of 30 healthy Caucasian individuals. Copper levels were assessed by atomic absorption spectroscopy.

Among RA patients the mean Cu level was significantly higher in serum and hair compartments and significantly lower in erythrocytes, compared with the control group (p<0.01). The Cp concentration was also higher in serum of RA patients (p<0.001). A statistically significant, positive correlation between the Cp serum concentration and the ESR values (r(s)=0.38; p<0.007) was found. No significant influence of pharmaceutical treatment (methotrexate, non-steroidal anti-inflammatory drugs, glucocorticoids, calcium, vitamin D3 and sulphasalazine) on serum Cu was found.

It seems that the 'copper status' in patients with RA, based on the measurement of Cu and Cp levels in blood serum is correlated with presence of the inflammatory process. The hair could serve as a useful, additional diagnostic material. Some other factors, different from the applied treatment, can probably influence the Cu levels in patients with RA.