Comprehensive assessment of cardiovascular-kidney-metabolic (CKM) syndrome: Novel tools for assessment of cardiovascular risk and kidney outcomes in long-term kidney transplant patients.

Background: Cardiovascular (CV)-kidney-metabolic (CKM) syndrome, a newly defined entity, offers a framework for assessing CV risk. Emerging evidence suggests that histone deacetylase sirtuin-1 (SIRT1) and adipokine chemerin hold promise as CKM markers. This study aimed to explore the relationship between CKM stage, clinical parameters, and both novel and established markers of CV and renal risk.

Methods: A cohort of 102 patients with long-term, stable kidney transplant (KTx) (>24 months) and median (interquartile range) follow-up of 83 (42-85) months was recruited alongside 32 healthy controls. Patients were classified into modified CKM stages following the American Heart Association guidance. Serum high-sensitivity interleukin-6 (hsIL-6), chemerin, and SIRT1 were measured using commercial immunoassay kits. The incidence of CV events (CVE), CV mortality, and permanent transfer to dialysis therapy were primary endpoints.

Results: CKM stage was associated with higher risk of CVE/CV death (HR 95% CI, 3.79 [1.16-12.42]; P = 0.03) and allograft loss (HR 95% CI, 2.05 [1.17-3.57]; P = 0.01). Elevated sirtuin-1 was associated with significantly lower risk of CV event/death (HR 95% CI, 0.11 [0.11-0.89]; P = 0.04), whereas high chemerin status was tied to dialysis risk (HR 95% CI, 5.77 [1.96-17.00]; P = 0.001) alone. In contrast to sirtuin-1, hsIL-6 and chemerin showed incremental changes across more advanced CKM stages, though statistically significant for hsIL-6 alone. In age-adjusted models for CV disease, independent associations with diabetes and total cholesterol were noted.

Conclusions: Classifying patients based on modified CKM stages offers valuable prognostic insights for stable KTx recipients, particularly when assessing reno-cardiovascular risk. The investigated serum markers may serve as supplemental tools for refining risk stratification.