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

Abstract

Objective: A cross-sectional study of 30 patients with primary Sjo ̈gren’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)-1b, IL-6, IL-10, tumour necrosis factor (TNF)-a, and gamma- interferon (g-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.