Cardiometabolic Index and Stress Urinary Incontinence in US Women: The Mediating Role of the Triglyceride Glucose Index

Background: Stress urinary incontinence (SUI) is a prevalent condition among women, significantly impairing their quality of life. Emerging evidence suggests that metabolic dysfunction may play a role in the development of SUI, although the underlying mechanisms remain unclear. This study aims to examine the association between the cardiometabolic index (CMI), a novel marker of metabolic health, and the risk of SUI in women.

Methods: Cross-sectional data from the 2001-2020 NHANES were analyzed. Weighted multivariable logistic regression models assessed the relationship between CMI and SUI risk, while restricted cubic spline (RCS) models examined potential nonlinear associations. Subgroup analyses and interaction tests were performed to explore how specific characteristics influenced the CMI-SUI relationship. Mediation analysis was performed to evaluate whether the triglyceride glucose (TyG) index mediated the CMI-SUI association. Sensitivity analyses using propensity score matching (PSM) ensured the robustness of the findings.

Results: Higher CMI was significantly associated with increased SUI risk in women (P < 0.001). RCS analysis revealed a nonlinear relationship, with a threshold at 1.64. Below this point, reducing CMI was significantly associated with a lower risk of SUI (overall P < 0.001, linear P < 0.001). Subgroup and interaction analyses showed stronger associations among women under 65 years, those with higher education, those without a history of hypertension or diabetes, and women taking oral contraceptives (P for interaction < 0.05). Mediation analysis showed that the TyG index completely mediated the relationship between CMI and SUI, accounting for 97.67% of the total effect. Sensitivity analyses using PSM confirmed the robustness of these results.

Conclusion: This study highlights that a higher CMI is associated with an increased risk of SUI in women, and this relationship may be largely mediated by the TyG index.