High Dietary Intake of Iron Might Be Harmful to Atrial Fibrillation and Modified by Genetic Diversity: A Prospective Cohort Study.

Some studies suggest an association between iron overload and cardiovascular diseases (CVDs). However, the relationship between dietary iron intake and atrial fibrillation (AF) remains uncertain, as does the role of genetic loci on this association. The study involved 179,565 participants from UK Biobank, tracking incident atrial fibrillation (AF) cases. Iron intake was categorized into low, moderate, and high groups based on dietary surveys conducted from 2009 to 2012. The Cox regression model was used to estimate the risk of AF in relation to iron intake, assessing the hazard ratio (HR) and 95% confidence interval (95% CI). It also examined the impact of 165 AF-related and 20 iron-related genetic variants on this association. Pathway enrichment analyses were performed using Metascape and FUMA. During a median follow-up period of 11.6 years, 6693 (3.97%) incident AF cases were recorded. A total of 35,874 (20.0%) participants had high iron intake. High iron intake was associated with increased risk of AF [HR: 1.13 (95% CI: 1.05, 1.22)] in a fully adjusted model. Importantly, there were 83 SNPs (11 iron-related SNPs) that could enhance the observed associations. These genes are mainly involved in cardiac development and cell signal transduction pathways. High dietary iron intake increases the risk of atrial fibrillation, especially when iron intake exceeds 16.95 mg. The association was particularly significant among the 83 SNPs associated with AF and iron, the individuals with these risk genes. Gene enrichment analysis revealed that these genes are significantly involved in cardiac development and cell signal transduction processes.

Relation of Life's Essential 8 to the genetic predisposition for cardiovascular outcomes and all-cause mortality: results from a national prospective cohort.

AIMS: To evaluate the independent, mediating, interactive, and associated effects of Life's Essential 8 (LE8) and genetic predisposition on the risk of cardiovascular outcomes and all-cause mortality. METHODS AND RESULTS: We retrieved a total of 254 783 individuals from the UK Biobank. LE8 was determined by eight metrics (nicotine exposure, physical activity, diet, sleep, body mass index, blood pressure, blood glucose, and blood lipids), and was characterized as low, moderate, and high cardiovascular health (CVH). Genetic predisposition was estimated using the polygenic risk score (PRS). Cox regressions were performed to evaluate the associations between LE8, PRS, and outcomes. During a median follow-up of 12.53 years, all-cause mortality occurred in 10 257 of 197 473 participants, cardiovascular mortality in 2074 of 215 675, and incident cardiovascular disease (CVD) in 71 774 of 215 675. Individuals with moderate or high CVH experienced a lower risk [hazard ratios (HRs) 0.33 to 0.81] of adverse health outcomes compared with their counterparts with low CVH. A substantial proportion (16.1∼69.8%) of health outcomes could be attributable to moderate or high LE8, and up to 51.2% of the associations between PRS and adverse outcomes were mediated by LE8. In high PRS group, individuals with high CVH had lower CVD mortality (HR: 0.26, 95% confidence interval: 0.18, 0.39), compared to those with low CVH. CONCLUSION: Ideal CVH was associated with lower risks of cardiovascular outcomes and all-cause mortality, with a more pronounced association observed in individuals with high PRS for CVD. Improving CVH according to LE8 guidelines should be encouraged, especially for those with PRS that indicate high CVD risk.

In the UK Biobank cohort of over 250 000 people, we found that participants achieved high scores on the Life's Essential 8 (LE8) guidelines had better health outcomes. The study also found that following LE8 guidelines helped reduce the risk of cardiovascular diseases, especially for those with a genetic predisposition to the condition. Thus, adopting a healthy lifestyle, as per the LE8 guidelines, could improve cardiovascular health and reduce the risk of death, even more than genetics alone. Furthermore, the study found that for every increase of one point in the LE8 score, the risk of adverse health outcomes decreased by 2­5%.