Early undifferentiated connective tissue disease (CTD). VI. An inception cohort after 10 years: Disease remissions and changes in diagnoses in well established and undifferentiated CTD

Objective. (1) To review the diagnoses after 10 years in patients who were identified within 12 months of the onset of well established and undifferen tiated connective tissue diseases (CTD). (2) To examine the death rates and disease remissions in these patients. Methods. This inception cohort of 410 patients had less than one year of si gns and/or symptoms of CTD. Diagnoses of rheumatoid arthritis (RA), systemi c lupus erythematosus (SLE), systemic sclerosis (SSc), and poly/dermatomyos itis (PM/DM) were made in 197 patients using accepted diagnostic and classi fication criteria, Diagnoses of undifferentiated CTD were made in 213 patie nts. These latter patients were placed in 3 categories: isolated Raynaud's phenomenon (RP), unexplained polyarthritis (UPA), and undifferentiated CTD (UCTD), defined as meeting at least 3 of ii specific manifestations of CTD. The diagnoses nd remissions in all patients after 10 years were determined . Results. Patients with well established CTD tended to remain with the origi nal diagnosis. The 10 year survival was at least 87% in ill diagnostic cate gories, with the exception of SSc, in which it was 56%. The progression of UPA to RA occurred infrequently. The presence of antinuclear antibodies sug gested that UPA may develop additional symptoms and/or a specific diagnosis , and RP in these patients increased the likelihood of progressing to UCTD or a specific well established CTD. Ten percent of patients with RP progres sed to SSc. In patients with UCTD, joint pain/tenderness and swelling count s were associated with progression to other diagnoses including RA,while ei ther serositis, malar rash, or discoid lupus suggested the eventual diagnos is of SLE. Conclusion, The survival of patients with SSc was poor, with most dying ear ly in the course of their disease. Remissions were seen in all groups of pa tients except SSc. The remissions were sometimes transient in SLE. Undiffer entiated disease at initial examination within 12 months of onset usually r emains undifferentiated.