Living and Dying with Primary Sjögren's Syndrome Studies on Aetiology, Treatment, Lymphoma, Survival and Predictors

Abstract: This work was aimed at improving our understanding of the course of primary Sjögren's syndrome (SS). The Malmö SS patient register and the 2002 American-European Consensus Criteria formed the basis of all studies. Helicobacter pylori (H. pylori) was not more prevalent in SS patients or associated with severe glandular or immunological dysfunction. Consequently, our results do not support screening for or eradication of latent H. pylori infection. Fatigue and reduced health-related quality of life contribute to sick leave, early retirement and mental distress. After 5 years quality of life was preserved at the same level, in contrast to the expected age-dependent decline in the normal population. Our double-blind randomized controlled trial with gammalinolenic acid (GLA), an essential omega-6 fatty acid, failed to alleviate fatigue, precluding a general recommendation of this complementary treatment. Longitudinal follow-up of glandular dysfunction revealed slight deterioration of objective measures after 5 years, predicted by low complement levels at baseline. However, the available measures of assessment suffer from considerable floor/ceiling effects. Linking our register to the Swedish Cause-of-Death and Cancer Registers, we calculated standardized mortality ratios (SMRs) and incidence ratios (SIRs) for solid and lymphoproliferative malignancies. SIR (95% confidence interval (CI)) for non-Hodgkin lymphoma: 15.57 (CI 7.77-27.85), cause-specific SMR for death from haematological neoplasms: 7.89 (CI 2.89-17.18). Aggressive diffuse large B-cell lymphomas predominated. Risk factor for both death and lymphoma was low complement at diagnosis. Novel strong predictors of lymphoma development were CD4+ T-lymphocytopenia (hazard ratio (HR): 8.14, CI 2.10-31.53) and a low CD4+/CD8+ T-cell ratio ?0.8 (HR 10.92, CI 2.80-41.83). All-cause mortality, cardiovascular mortality and the incidence of non-haematological malignancies were not increased.