Do antimalarials protect against damage accrual in primary Sjögren's syndrome? Results from a Latin-American retrospective cohort.

OBJECTIVES: To assess the use of antimalarials and to evaluate their association with damage accrual in a Latino-American cohort of patients with primary Sjögren's syndrome (pSS).

METHODS: We included 377 patients attending three tertiary referral centers from: Argentina (n=110), Brazil (n=49) and Mexico (n=218). We retrospectively registered demographics, disease duration and use of prednisone (PDN), immunosupressors and antimalarials. We scored the cumulative ESSDAI and the SSDDI at last follow-up.

RESULTS: Most patients were females, median disease duration 6 years, mean SSDDI score 2.7±1.8, mean cumulative ESSDAI score 9.3±8.3, 39% used PDN and 37.4% immunosupressors. A total of 191 patients (50.6%) had ever used antimalarials, mean use 43.5±40 months, being the main indication arthritis. These patients had a longer disease duration, used more PDN and immunosupressors and had lower SSDDI scores. The pleuro-pulmonary domain was significant different among groups (6.7% antimalarials users vs.14.9% not users, p=0.01). At the logistic regression, the pleuro-pulmonary domain (OR 0.37, 95% CI 0.17-0.78, p=0.01), the age (OR 0.97, 95% CI 0.96-0.99, p=0.01) and the disease duration (OR 1.07, 95% CI 1.03-1.1, p=0.0001) were associated with antimalarials use. When we compared patients with a SSDDI ≥3 vs. SSDDI<3, in the multivariate analysis the use of antimalarial was protective (OR 0.58, 0.36-0.93 CI 95%, p=0.02) and the cumulative ESSDAI a risk factor for damage accrual (OR 1.1, 1.07-1.15 CI 95%, p<0.001).

CONCLUSIONS: Antimalarials were frequently used in pSS and seemed to protect against damage accrual, specifically at the pleuro-pulmonary domain. This finding should be confirmed in prospective studies.