Ten-year observation of patients with primary Sjögren's syndrome: Initial presenting characteristics and the associated outcomes.

AIM/INTRODUCTION: Primary Sjögren's syndrome (pSS) is a prototypical systemic autoimmune disease that manifests with various signs and symptoms. Although some studies have examined these manifestations over the long-term course of the disease, the association between initial clinical and immunological factors and subsequent long-term manifestations has not been fully elucidated. The aim of this study is to identify initial clinical and immunological factors associated with subsequent manifestations in patients with pSS.

METHOD: A retrospective review was performed in pSS patients who were followed up over a 10-year period in our department. Clinical and immunological data, including serum immunoglobulin (Ig) and autoantibody levels, were collected and statistically analyzed.

RESULT: We analyzed 91 patients who were followed up in our department. The proportion of patients with extraglandular involvement decreased from 90% to 73%, while eight patients developed extraglandular organ involvement. Extraglandular involvement at 10 years more frequently occurred in patients with hyper-IgG than those without hyper-IgG at initial testing (P < 0.01). Extraglandular organ involvement at 10 years more frequently occurred in rheumatoid factor (RF)-positive patients at the time of SS diagnosis (P < 0.05). Malignancy occurred in 9% of patients. Age, lower CH50 and thrombocytopenia were significantly associated with malignancy. Extraglandular organ involvement was associated with the presence of hyper-IgG and RF positivity (P < 0.01 and P < 0.05).

CONCLUSION: Our study identified important initial clinical and immunological factors associated with subsequent manifestations in patients with pSS over a long follow-up period. pSS patients with RF and hyper-IgG at diagnosis may have a higher risk of subsequent extraglandular involvement.