To study whether clinically observed tenderness and/or swelling of a wrist joint over the first 3 years after diagnosis predict the development of erosions in radiographs of the same joint at 5 years in patients with early rheumatoid arthritis (RA).
A total of 58 patients with recent onset RA were enrolled in a prospective RA study at Jyväskylä Central Hospital in 1983-85. Physical examination including joint counts was performed 6 times over 3 years (at 0, 6, 12, 18, 24, and 36 mo). Radiographs of hands and feet taken at the 5-year visit were scored according to the Larsen method (0-1 = non-erosive; 2-5 = erosive). At each visit, the wrist joints were assessed for tenderness (0/1) and swelling (0/1). A frequency (ranging from 0 to 6) was calculated for 4 inflammation categories tenderness, swelling, tenderness or swelling, and tenderness and swelling over the 3 years. Percentages of wrist joints with erosions on the 5-year radiographs were calculated for the frequency groups 0, 1, 2-3, and 4-6 of each category. Two patients died, and 5 wrists were erosive at baseline. Thus the data for 107 wrist joints of 54 patients were available for analyses.
A statistically significant correlation was seen in the frequency of clinical inflammation and the development of erosions. Only one (3.3%) wrist with no tenderness in 6 examinations over the first 3 years developed erosions over 5 years, while 13 (59.1%) wrists that were tender 4-6 times in 6 examinations developed erosions. The corresponding percentages were 4.4% and 50.0% for wrists with swelling, 3.4% and 51.6% for wrists with tenderness or swelling, and 6.1% and 75.0% for wrists with tenderness and swelling.
Radiographic erosions develop rarely without preceding clinically detectable inflammation in the joints of patients with early RA.