Correlation between testosterone and the inflammatory marker soluble interleukin-6 receptor in older men

Context: An age-associated decline in testosterone (T) levels and an increase in proinflammatory cytokines contribute to chronic diseases in older men. Whether and how these changes are related is unclear. Objective: We hypothesized that T and inflammatory markers are negatively correlated in older men. Design: This was a cross-sectional study. Setting: A population-based sample of older men was studied. Participants and Measures: After excluding participants taking glucocorticoids or antibiotics or those with recent hospitalization, 467 men, aged 65 yr or older, had complete determinations of total T, bioavailable T, SHBG, albumin, IL-6, soluble IL-6 receptor (sIL-6r), TNF-alpha, IL-1 beta, and C-reactive protein. Results: After adjusting for potential confounders, sIL-6r was significantly and inversely correlated with total T (r = -0.20; P < 0.001) and bioavailable T (r = -0.12; P < 0.05). T was not correlated with any other inflammatory marker. Conclusions: These preliminary findings suggest an inverse relationship between T and sIL-6r. Longitudinal studies are needed to establish the causality of this association.