Background: Serum cystatin C is not only a marker of renal function but also acts as an independent risk factor for cardiovascular damage, heart failure, and death. It is known that the initiation and progression of these cardiovascular events contributes to renal dysfunction and chronic inflammation. In this study, we investigated the relationship between cystatin C and proinflammatory cytokines.
Methods: Eighty-eight patients with essential hypertension participated in the study, which involved measuring proinflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and C reactive protein (CRP).
Results: Positive correlations were detected between cystatin C and estimated glomerular filtration rate (eGFR) (r = -0.503, p < 0.001), systolic blood pressure (r = -0.246, p = 0.034), and pulse pressure (r = -0.295, p = 0.010). In contrast, serum creatinine correlated only with eGFR (r = -0.755, p < 0.001) and eGFR correlated only with age (r = -0.339, p = 0.001) and not with the other clinical parameters, whereas cystatin C also correlated with log natural (ln) IL-6 (r = -0.247, p = 0.033) and ln TNF-α (r = -0.405, p < 0.001) but not with CRP (r = -0.188, p = 0.108). In contrast, plasma creatinine and eGFR did not correlate with any of these proinflammatory cytokines. Stepwise regression analysis showed that ln TNF-α, eGFR and pulse pressure were independent determinants of serum cystatin C concentration.
Conclusion: This study showed that cystatin C is a marker of inflammation as well as renal function.