# Association of composite dietary antioxidant index with incidence and mortality of aortic aneurysm and dissection: insights from the UK Biobank

## TL;DR

Higher dietary antioxidant intake is linked to lower risk and mortality from aortic aneurysm and dissection, according to a study of over 170,000 people.

## Contribution

This study is the first to show a link between the composite dietary antioxidant index and aortic aneurysm and dissection outcomes.

## Key findings

- Higher CDAI scores were associated with a 7% lower risk of developing aortic aneurysm and dissection.
- Participants with the highest CDAI had a 17% lower risk of mortality from aortic aneurysm and dissection.
- Metabolic indicators like uric acid and CRP partially explained the protective effect of dietary antioxidants.

## Abstract

The composite dietary antioxidant index (CDAI) is a scoring system designed to assess overall dietary antioxidant capacity and has been associated with a reduced risk of cardiovascular diseases. However, its specific impact on aortic aneurysm and dissection (AA/AD) remains unclear. This study aimed to investigate the associations of CDAI with both the incidence and mortality of AA/AD.

In this UK Biobank-based study, univariate and multivariate logistic regression models were used to assess the association between CDAI and the incidence of AA/AD, the association of CDAI with mortality was evaluated using Cox proportional hazards models. We employed restricted cubic spline (RCS) analyses to examine potential linear or non-linear relationships between the key nutrient components of the CDAI and the outcomes. Furthermore, mediation analysis was performed to assess the potential mediating effects of selected metabolic indicators.

A total of 172,450 participants were included in this study, of whom 1,486 developed AA/AD. Univariate logistic regression analysis revealed a significant inverse association between CDAI and the incidence of AA/AD (OR = 0.93, 95% CI: 0.88–0.99, p = 0.024). A significantly lower risk of AA/AD mortality was observed in participants within the highest quartile of CDAI compared to those in the lowest quartile (HR = 0.83, 95% CI: 0.71–0.96, p = 0.018), based on the Cox regression analysis. RCS analysis indicated a linear relationship between CDAI and the mortality of AA/AD (P for overall < 0.001; P for nonlinear > 0.05). Furthermore, mediation analysis suggested that uric acid, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), and high-density lipoprotein cholesterol (HDL-C) mediated the association between CDAI and AA/AD incidence.

This study supports the pathogenic role of oxidative stress and inflammation in AA/AD, demonstrating that a higher CDAI is associated with lower incidence and mortality of AA/AD in a UK-based adult population. These findings provide new insights, suggesting that dietary antioxidant intervention could serve as a potential preventive strategy against these conditions.