Health-related quality of life in patients with primary Sjögren's syndrome: relationship with serum levels of proinflammatory cytokines.

OBJECTIVE: A cross-sectional study of 30 patients with primary Sjögren's syndrome (pSS) was performed to analyse the health-related quality of life and its relationship with serum levels of macrophage- and lymphocyte-derived cytokines. PATIENTS AND METHODS: Health-related quality of life was evaluated using the 36-item Short Form Health Survey (SF-36). Serum levels of interleukin (IL)-1beta, IL-6, IL-10, tumour necrosis factor (TNF)-alpha, and gamma-interferon (gamma-INF) were analysed by a sandwich immunoassay-based protein array system. RESULTS: Each of the eight scales of the SF-36 evaluating quality of life, as well as the physical composite score (PCS) and the mental composite score (MCS), showed a decrease in pSS patients. Similarly, patients with pSS showed significantly increased concentrations of each of the five cytokines analysed, when compared with the healthy control group (n = 20). In pSS patients, a significant negative correlation was detected between serum levels of IL-6 and the PCS of the SF-36. Those patients with concentrations of IL-6 higher than those of the healthy controls showed a significantly lower score in the dimensions of bodily pain and physical functioning, and in the PCS. CONCLUSIONS: Patients with pSS showed increased levels of several macrophage- and lymphocyte-derived cytokines, indicating the existence of an immune activation state. Serum levels of one of these cytokines, IL-6, were correlated with poor quality of life in these individuals.

Implications of immunomodulatory interleukins for the hyperimmunoglobulinemia of Sjögren's syndrome.

A prospective study of 37 patients with pSS and 20 healthy controls was performed to analyze the differences in circulating levels of macrophage-derived and Th1/Th2 cytokines which could explain the hyperimmunoglobulinemia, characteristic of primary Sjögren's syndrome (pSS). Serum levels of interleukin (IL)-6, IL-10, IL-12, gamma-interferon (gamma-INF) and IL-4 were analyzed by a sandwich immunoassay-based protein array system. When compared with the control group, higher levels of IL-6, IL-12 and IL-10 and a lower Th1/Th2 ratio, as demonstrated by the gamma-INF/IL-4 ratio, were detected in patients. The levels of IL-4 were notably higher in pSS patients with monoclonal gammopathy. Serum IL-4 and IL-10 levels and immunoglobulin G concentrations were significantly correlated. In conclusion, patients with pSS show a state of macrophage and T-lymphocyte activation with increased concentrations of cytokines implicated in the differentiation of B cells and secretion of immunoglobulins.