Elevated Sirtuin 1 Levels in Patients with Chronic Kidney Disease, Including on Peritoneal Dialysis: Associations with Cardiovascular Risk and Peritoneal Fibrosis.

Sirtuin 1 (SIRT1) is implicated in oxidative stress, inflammation, and fibrosis-processes central to chronic kidney disease (CKD) and cardiovascular complications. Increased serum levels of SIRT1 have been reported in dialysis patients, and its role in peritoneal fibrosis, a leading cause of peritoneal dialysis failure, is well established. This study evaluated serum SIRT1 levels in 165 participants: peritoneally dialyzed patients (CAPD), conservatively treated CKD patients (CT), and healthy controls. Serum SIRT1 was measured by ELISA and analyzed alongside clinical factors. SIRT1 concentrations were markedly elevated in CAPD patients compared to both CT patients and controls. In CAPD patients, SIRT1 levels were not influenced by age, sex, dialysis adequacy, residual renal function, or comorbidities, but were higher in those with impaired left ventricular relaxation. Pharmacotherapy affected SIRT1 levels. Multivariate analysis identified phosphate and cholesterol as independent predictors of SIRT1. Our study suggests that serum SIRT1 levels may reflect diverse pathophysiological processes in CKD patients, including those on peritoneal dialysis. Elevated SIRT1 may indicate compensatory mechanisms related to renal dysfunction and cardiovascular stress. Future research on larger, pharmacologically homogeneous groups is warranted to clarify SIRT1's role in peritoneal fibrosis and its potential as a biomarker of cardiovascular and renal complications in CKD.