Serum Gastrin concentration in patients with rheumatoid arthritis: effect of long-term immunosuppressive or antidopaminergic treatment.

In an attempt to further evaluate the conflicting incidence of hypergastrinemia in patients with rheumatoid arthritis (RA), serum gastrin concentration has been determined in 58 RA patients and in 58 healthy subjects. Mean levels were significantly higher in RA patients than in controls, although clearly high values were only found in 3 subjects with severe hypochloridria. During one year of immunosuppressive treatment in 12 RA patients with cyclophosphamide plus colchicine serum gastrin levels did not change, while a significant decrease was observed in another 12 patients after 2 months' treatment with haloperidol, a dopamine receptor blocker; this decrease was sustained throughout the one year treatment. Indomethacin administration up to 6 months did not change serum levels in a control group of 12 RA patients. Serum gastrin concentration in patients treated with haloperidol was significantly lower than in those treated with indomethacin at 2 and 6 months, while no significant differences were observed between cyclophosphamide- and indomethacin-treated groups. These results confirm and extend previous studies showing inhibition of gastrin secretion by antidopaminergic drugs. No correlations were observed between serum gastrin levels and inflammatory indices, both in basal conditions and during any drug treatment.