THE LONG-TERM OUTCOMES OF RHEUMATOID-ARTHRITIS - A 23-YEAR PROSPECTIVE, LONGITUDINAL-STUDY OF TOTAL JOINT REPLACEMENT AND ITS PREDICTORS IN1,600 PATIENTS WITH RHEUMATOID-ARTHRITIS

Objective. Although total joint arthroplasty (TJA) is a common procedu re and an important outcome in rheumatoid arthritis (RA), little is kn own about its prevalence, failure rate, or predictors over the course of the illness. The current stud evaluated these factors in 1,600 cons ecutive RA patients seen during a period of observation that extended 23 years. Methods. Beginning in 1974, data from 34,040 RA patient visi ts were entered prospectively into a computer databank. Data consisted of laboratory, radiographic, physical examination, and self-report qu estionnaires. At each assessment, we also noted a complete surgical hi story. Patients were also followed up by questionnaires that were mail ed at 6-month intervals. Results. Kaplan-Meier life-table estimates in dicated that 25% of RA patients will undergo total joint arthroplasty (TJA) within 21.8 years of disease onset. For patients with 1 TJA, 25% had a TJA in a different joint within 0.92 years and 50% within 7.0 y ears. Ten years after TJA, similar to 6% of implanted knees and 4% of implanted hips had been replaced with a second TJA, and 12% and 13% of the joints had either a second TJA or a TJA-related operation, respec tively. In Cox regressions, a large series of clinical and laboratory variables, which primarily reflected disease activity, predicted TJA. Smoking, either past or present, had a protective effect. Patients wit h highly abnormal values on the Health Assessment Questionnaire Disabi lity Scale, global severity, and erythrocyte sedimentation rate had a 3-6 times increased risk of TJA. Conclusion. TJA, a marker of joint fa ilure and of RA outcome, is predicted by self-report assessments of se verity and function, and by a series of laboratory, radiographic, and clinical variables. Prediction improves with the extent of observation , and 2-year observations approach full-study observations in their ac curacy, Most TJAs survive for a long time in RA.