Early undifferentiated connective tissue disease. V. An inception cohort 5 years later: Disease remissions and changes in diagnoses in well established and undifferentiated connective tissue diseases

Objective. To review the diagnoses after 5 years in patients who were identified within 12 months of the onset of well established and undifferentiated connective tissue diseases (CTD); to examine death rates and disease remissions in these patients. Methods. This inception cohort of 410 patients was identified in 10 academic rheumatology practices. They had less than one year of signs and/or symptoms of CTD. Diagnoses of specific well established CTD were made using accepted diagnostic and classification criteria. The diagnoses after 5 years were determined. Results. Patients with well established CTD tended to remain with the original diagnosis. The progression of unexplained polyarthritis to rheumatoid arthritis occurred infrequently. Ten percent of patients with isolated Raynaud's phenomenon progressed to systemic sclerosis (SSc). The 5 year survival was over 90% in all diagnostic categories, with the exception of SSc, in which it was 64%. Conclusion. Patients with a well established CTD usually continued with the same diagnosis. Patients with undifferentiated CTD tended to remain undifferentiated or to remit.