A three-year prospective study of systemic manifestation in rheumatoid arthritis

Summary

Rheumatoid arthritis (RA) as a systemic disease can attack many other organs in addition to the joints. A variety of pathological lesions of the blood vessels are responsible for the extra-articular features (EAF). In the present study, we investigated firstly whether the presence of blood vessel changes in one organ—namely the skin—may indicate blood vessel pathology and, consequently, EAF in other organs. Secondly, we investigated the number of EAF in individual patients with RA, and observed whether this changed during the course of the disease. Fifty-one RA-patients (40 female, 11 male; ages had a mean of 49.5, minimum 19, maximum 73 years; mean duration of RA was 7.3, minimum 0.25, maximum 41 years) were included in the study. Punch biopsies from the posterior calf were examined immunohistologically for vessel wall immune deposits. Further, EAF were determined by means of instrumental clinical methods such as pulmonary function test, echocardiography, electromyography, and nerve conduction velocity measurement. At the first investigation 21/51 patients had skin vessel wall immune deposits (SVWID). Five patients—all showed SVWID at first investigation—died during the three-year investigation period, 10 patients could not be followed-up for unknown reasons; the skin biopsy of one patient could not be assessed. At the final investigation, we found SVWID in 11/35 patients. SVWID-positive patients had more EAF compared to SVWID-negative patients; this was true both, at the first investigation (1.85 EAF/patient vs 1.05 EAF/patient) and at the final investigation (1.91 EAF/patient vs 0.67 EAF/patient). However, if patients with and without SVWID at first investigation were followed-up independent of their belonging to SVWID-positive or SVWID-negative group at final investigation number of EAF did not change significantly in both patient groups. It can be concluded from these data that in RA-patients SVWID are poor indicators of prognosis regarding survival. Further, SVWID indicate a greater risk for presence of EAF. However, SVWID were not associated with an increase in the absolute number of EAF occuring during the period of observation in surviving patients.