BACKGROUND: Information regarding the association between cardiovascular health (CVH) as assessed using Life's Essential 8 (LE8) approach and all-cause mortality in adults with early-onset cardiovascular diseases (CVDs) is limited. OBJECTIVE: In this study, we aimed to assess the association between CVH constructed by the LE8 metrics and all-cause mortality in Chinese individuals with early-onset CVDs, including myocardial infarction, heart failure, atrial fibrillation, ischemic stroke, and hemorrhagic stroke as well as in those who had undergone coronary artery bypass surgery or coronary intervention. METHODS: Data of 3454 participants who were first diagnosed with early-onset CVDs (men aged <
55 years and women aged <
65 years with CVDs) in the Kailuan study from 1 January 2006 to 31 December 2020 were analyzed. Assessment of CVH (score ranging from 0 to 100 points) was made using the LE8 metrics (including diet, physical activity, nicotine exposure, sleep duration, body mass index [BMI], lipid, blood glucose, and blood pressure). All-cause mortality information was collected from provincial vital statistics offices. Cox proportional hazard regression models and restricted cubic splines were utilized to examine associations between the CVH scores and all-cause mortality in adults with early-onset CVDs. RESULTS: During a mean follow-up of 6.78 years (interquartile range [IQR]: 3.36-10.5 years), 460 deaths were documented. After controlling for demographic variables, lifestyles, and major clinical factors, higher CVH scores were associated with lower risks of all-cause mortality among participants with early-onset CVDs. The corresponding hazard ratios (HRs) with 95% confidence intervals (CIs) were 0.64 (0.49, 0.82) comparing two extreme quartiles of CVH scores and 0.85 (0.77, 0.82) for each 10-point increment in CVH score (p CONCLUSION: Our findings supported the beneficial role of higher CVH scores in all-cause mortality among adults with early-onset CVD.