The prognostic significance of stress hyperglycemia ratio in evaluating all-cause and cardiovascular mortality risk among individuals across stages 0–3 of cardiovascular–kidney–metabolic syndrome: evidence from two cohort studies

An increased SHR value is positively associated with an elevated likelihood of all-cause mortality within individuals diagnosed with CKM syndrome across stages 0-3, yet it shows no significant association with CVD mortality. SHR is an important tool for predicting long-term adverse outcomes in this population. Cardiovascular-kidney-metabolic (CKM) syndrome emphasizes the interconnectedness of cardiovascular, kidney, and metabolic diseases. The stress hyperglycemia ratio (SHR) is a novel marker reflecting stress-induced glucose fluctuations, but its prognostic value in individuals with CKM syndrome (stages 0-3) remains uncertain. This study explores the association between SHR and all-cause and cardiovascular disease (CVD) mortality in this population. Our findings indicate that SHR is significantly associated with an increased risk of all-cause mortality (HR = 1.09, 95% CI 1.04-1.13), but not with CVD mortality (HR = 1.00, 95% CI: 0.91-1.11). Mediation analysis results suggested that the relationship between SHR and all-cause mortality risk is partially mediated by RDW, albumin, and RAR. Specifically, the mediating effects were - 17.0% (95% CI - 46.7%, - 8.7%), - 10.1% (95% CI - 23.9%, - 4.7%), and - 23.3% (95% CI - 49.0%, - 13.0%), respectively. Validation using the CHARLS database supports these findings. These results suggest that SHR could serve as a prognostic biomarker for long-term mortality risk in CKM patients, offering potential clinical utility in risk stratification and management.