Diagnostic Value of Sirtuin-1 in Predicting Contrast-Induced Nephropathy After Percutaneous Coronary Intervention

Objectives: Contrast-induced acute kidney injury (CI-AKI) remains a frequent and serious complication after cardiac catheterization. Sirtuin-1 (SIRT1), a NAD+-dependent deacetylase, plays a central role in renal protection against ischemia-reperfusion injury, inflammation, and vascular dysfunction. We aimed to investigate whether serum SIRT1 levels could serve as an early diagnostic biomarker for CI-AKI. Methods: This prospective case-control study included 50 patients undergoing elective percutaneous coronary intervention (PCI) for stable angina. Serum SIRT1 levels were measured at baseline, 24 h, and 72 h post-PCI. The occurrence of CI-AKI was defined by a standard rise in serum creatinine, and patients were stratified accordingly. Results: Although SIRT1 levels tended to be lower in patients who developed CI-AKI (n = 17) compared to those without (n = 33), the differences were not statistically significant at any time point (p > 0.05). However, a significant between-group difference was observed in the 72-h change in SIRT1 levels (Δ0-72 h, p = 0.037), with a greater decline in the CI-AKI group. Multivariable logistic regression also revealed a trend-level inverse association between 72-h SIRT1 levels and CI-AKI (β = -0.536, p = 0.099). Conclusions: While SIRT1 is biologically plausible as a renal protective factor, our findings suggest that serial SIRT1 measurement may offer added value as a dynamic biomarker rather than a static diagnostic tool. Confirmatory trials incorporating serial SIRT1 measurements may help translate this molecular signal into clinically actionable tools for early detection of CI-AKI.