Introduction: The combination of easy-to-obtain validated biomarkers is interesting in the prognostic evaluation of patients at cardiovascular risk in a precision medicine scenario. The evaluation of the effect modification of insulin resistance and liver fibrosis with the Triglyceride-Glucose index (TyG) and Fibrosis-4 index (FIB4) might provide prognostic information in patients at cardiovascular risk. Patients and methods: A retrospective cohort study was performed with 2055 patients recruited in the Vascular Metabolic CUN cohort. The studied outcome was the incidence rate of major cardiovascular events (MACE). The Systematic Coronary Risk Evaluation (SCORE), FIB4 and TyG indexes were calculated according to validated formulas. Results: FIB4 and TyG showed a synergistic interaction using validated cut-offs for both indexes in the prediction of MACE (Hazard ratio (HR) 1.05 CI95% 1.01-1.08) which remained after adjustment by age, sex, SCORE subgroup, presence of diabetes, or previous MACE using standardized cut-off (HR 2.29 CI95% 1.33-3.94). Finally, a subgroup with significant TyG and FIB4 showed a higher cardiovascular risk in the study population (adjusted HR 3.34 CI 95% 1.94-5.77). Conclusion: The combined interpretation of TyG and FIB4 indexes might have a potential predictive value of major cardiovascular events.