Abstract 1090: Clinical and Immunological Expression of the Epidemiologic Subsets of Primary Sjögren’s Syndrome. Multicenter Study of 1000 Patients
Thomas Grader-Beck
Authors:
M. Ramos-Casals, R. Solans, J. Rosas, M. T. Camps, A. Gil, J. del Pino, J. Calvo-Alen, J. Jiménez-Alonso, M. L. Micó, J. Beltrán, R. Belenguer, L. Pallarés
Background
To determine the influence of the epidemiologic characteristics in the clinical and immunologic expression of primary Sjögren syndrome (pSS) in a large cohort of patients.
PATIENTS.
We included 1000 consecutive patients from the database of the GEMESS Study Group (updated, December, 2006), and studied the following epidemiologic subsets: age 70 years, gender and incident cases.
Results
The cohort consisted of 926 women and 74 men (ratio, 12:1). Mean age at diagnosis was 53 years (range, 15-87) and at the time of protocol inclusion 59 (range, 16-94). There were 201 incident and 783 prevalent cases. Multivariate analysis identified the following significant independent variables. Men had a lower frequency of positive ocular tests (84% vs 94%, p=0.001), Raynaud phenomenon (7% vs 19%, p=0.027) and autoimmune thyroiditis (5% vs 15%, p=0.032) compared with women. Patients with age <35 years had a lower prevalence of xerostomia (86% vs 98%, p<0.001), higher frequency of anti-Ro antibodies (73% vs 49%, p<0.001), low C3 (27% vs 8%, p<0.001) and low C4 levels (26% vs 8%, p35. In contrast, elderly patients (age >70) had a lower prevalence of ANA (78% vs 86%, p=0.041), arthralgias (43% vs 53%, p=0.018) and leukopenia (12% vs 18%, p=0.039), but a higher frequency of lung involvement (19% vs 8%, p<0.001), neuropathy (16% vs 9%, p=0.001) and anemia (24% vs 16%, p=0.01). Clinical and immunological expression of prevalent cases was significantly different from that of incident cases, with a higher prevalence of parotidomegaly (30% vs 19%, p<0.001) and anti-Ro antibodies (54% vs 36%, p<0.001).
Conclusions
Epidemiologic characteristics have a significant impact on the results of the diagnostic tests, the prevalence and diversity of the extraglandular involvement and the frequency of the main immunologic markers of pSS patients. pSS is a systemic disease that can express in many guises depending on the epidemiologic profile
Editorial Comment
The study by Ramos-Casal et al. represents one of the largest epidemiological studies of patients with Sjögren’s disease. According to their analysis, young patients less than 35 years of age, exhibit a more activated immune response with higher frequency of anti-Ro antibodies and lower complements. This is an interesting finding in light of reports that Sjögren’s patients with low C3 exhibit a higher risk of lymphoma. Similarly, the higher risk of lung involvement in patients older than 70 years of age is striking. It would be useful to better understand the specific pathological lung phenotype and the severity of the disease. Finally, the higher incidence of anti-Ro antibodies in prevalent versus incident cases is somewhat surprising. In systemic lupus erythematosus, the vast majority of patients develop anti-Ro antibodies before the onset of clinical disease. This finding points to potential differential pathophysiologic processes in SLE versus Sjögren’s disease.
