Association of the ‘Life’s Essential 8’ with FeNO and all-cause mortality: a population-based study in U.S. adults

BACKGROUND: The 'Life's Essential 8' (LE8), a recent framework introduced by the American Heart Association (AHA), refines and expands the concept of wellness, with a particular emphasis on promoting cardiovascular health. The fractional exhaled nitric oxide (FeNO) score, a non-invasive and easily obtainable biomarker, offers a convenient method for evaluating respiratory conditions such as asthma. While both LE8 and FeNO represent emerging and widely recognised indicators of health, research exploring their interrelationship remains limited. This study aims to examine the associations between LE8, FeNO, and all-cause mortality. METHODS: A total of 14,293 eligible participants, aged ≥18 years, were enrolled from the National Health and Nutrition Examination Survey (NHANES) database spanning 2007-2012. This observational cohort study integrated baseline NHANES data with mortality records from the U.S. National Death Index through 2021. To assess the association between LE8 and FeNO, we employed multiple linear regression models, both with and without adjustments for demographic factors and health-related practices. Additionally, these data were utilised to explore the relationships between various health determinants and all-cause mortality. RESULTS: In this observational analysis, we found that an increase in the LE8 score was positively associated with elevated FeNO levels, a marker implicated in immune responses to respiratory diseases. Furthermore, higher LE8 scores were inversely associated with survival risk in the population, suggesting a potential protective effect on survival in the studied population. CONCLUSIONS: Our findings suggest that primary and tertiary prevention efforts to promote cardiovascular health should be strengthened, especially those targeting unhealthy factors and behaviours to improve cardiorespiratory fitness and reduce survival risk.