Cathepsin S is independently associated with cytokine mediated inflammation in elderly men Conclusion: Higher serum levels of Cathepsin S were independently associated with higher CRP and IL-6 in a community– based sample of elderly men. Our data provides support for the notion that Cathepsin S is involved in inflammatory processes, possibly leading to atherosclerosis and cardiovascular disease. Background: Cathepsin S is a lysosomal protease that has been suggested to play a key role in the development of atherosclerosis and cardiovascular disease by degradation of vascular extracellular matrix. Previous studies have suggested that cathepsin S provides a molecular link between obesity and atherosclerosis, possibly via increased inflammatory activity. Yet, the association between circulating cathepsin S and inflammation markers has not previously been reported in the community. Aim: To investigate the association between plasma levels of cathepsin- S, C-reactive protein (CRP) and Interleukin 6 (IL-6), in the community. Methods: Serum levels of cathepsin S, CRP, IL-6 were measured in frozen samples from the Uppsala Longitudinal Study of Adult Men (ULSAM), a community-based cohort of elderly men (n=999, mean age 71 years). Results: Cross-sectional association between Cathepsin S, CRP and IL-6 at age 70 showed that one standard deviation (SD) higher serum Cathepsin S was significantly associated with 0.14 SD higher serum CRP and 0.07-0.08 SD higher serum IL-6 when adjusting for age, life style factors (body mass index, physic activity and smoking), cardiovascular risk factors (hypertension, dyslipidemia, previous cardiovascular disease and diabetes and smoking), and the combination of all covariates