Sirtuin-1 (SIRT1) has long been associated with beneficial metabolic effects and vascular homeostasis. However, the role of endogenous SIRT1 in patients with aortic dissection (AD) has not been fully elucidated. This study measured for the first time serum SIRT1 levels in AD patients and control subjects and explored the correlations between its serum levels and various clinic parameters. SIRT1 concentrations in plasma of 46 patients with AD and 74 control subjects were measured by Enzyme-linked immunosorbent assay (ELISA). Anthropometric parameters, blood lipids, creatinine, blood urea nitrogen, uric acid (UA) and fasting glucose were measured. Circulating levels of SIRT1 were significantly decreased in AD patients than in control subjects (1.52 +/- 0.64 versus 1.87 +/- 0.68 ng/ml, P = 0.01). Interestingly, analysis of the data showed a negative correlation between SIRT1 levels and UA in all subjects (r = -0.22; P = 0.02). In addition, plasma SIRT1 levels tended to correlate negatively with UA in AD patients (r = -0.28; P = 0.06). To conclude, circulating concentrations of SIRT1 are significantly decreased in AD patients and negatively correlated with UA. Our results suggest that SIRT1 may play a role in the pathogenesis of AD and could be a potential biomarker for AD.