We followed the levels of serum IgA-alpha-1-antitrypsin (IgA-AT) complex in 37 patients with early rheumatoid arthritis (RA) during the first 3 years of the disease. The changes in IgA-AT were correlated with a radiological damage score (DS) of the hands assessed according to Larsen. At the onset of the disease, the IgA-AT serum concentration was significantly higher as compared to the control group (0.72 +/- 0.22 U vs 0.29 +/- 0.14 U, P < 0.01). The level significantly decreased during the 3-year observation period. The DS was significantly higher after 3 years. However, this difference was due to changes in only 11 patients; in 26 patients the DS was almost unchanged. In the group of 11 patients with radiological progression, the level of IgA-AT either remained high or increased significantly (0.95 +/- 0.18 U at the onset, 0.97 +/- 0.25 U after 3 years), whereas we observed a decrease in IgA-AT in 26 patients without radiological progression (0.63 +/- 0.16 U at the onset of the disease, 0.45 +/- 0.10 U after 3 years, P < 0.01). Moreover, a relationship between changes in IgA-AT serum level and radiological progression was shown (r = 0.60, P < 0.01). Our studies suggested that the relationship between IgA-AT level and radiological progression of the disease should be considered. We cannot exclude the possibility that the constant high level of IgA-AT may cause worsening in bone erosions.