Background: Compared to chronological age, biological age (BA), a concept introduced in recent years, more accurately reflects the true aging status of the body. While biological aging has been found to be associated with various cardiovascular diseases, its relationship with abdominal aortic aneurysm (AAA) remains unclear. Methods: This study utilized data extracted from UK Biobank for analysis. Telomere length (TL), and BA acceleration calculated using the Klemera-Doubal (KDM) and PhenoAge methods, were employed as surrogate measures to assess biological aging. Cox regression was primarily performed to explore the association between biological aging and AAA risk. Genetic susceptibility was assessed by constructing a polygenic risk score (PRS). Results: This study included 311,646 participants, predominantly women and White, with a median age of 58 years. During a median follow-up of 12.54 years, 1,339 new cases of AAA (4.3‰) were reported. Each standard deviation (SD) decrease in TL was associated with a 20% increased risk of AAA (HR=1.20, 95% CI=1.14-1.27); each SD increase in KDM-BA acceleration was associated with a 21% increased risk (HR=1.21, 95% CI=1.12-1.29); and each SD increase in PhenoAge acceleration was associated with a 40% increased risk (HR=1.40, 95% CI=1.32-1.48). These associations were independent of genetic risk, as assessed by the PRS, and demonstrated a joint effect with genetic predisposition on the long-term risk of AAA. Conclusion: Accelerated biological aging was longitudinally associated with an increased risk of AAA, suggesting it may be a significant factor and potential biomarker for the occurrence of the condition.

The authors have declared no competing interest.

This work was supported by the National Natural Science Foundation of China (Grant Nos. 82470054 and 82300081), the Hunan Provincial Natural Science Foundation of China (Grant Nos. 2023JJ40963, 2024JJ6620, and 2024JJ6673), and the Project Program of the National Clinical Research Center for Geriatric Disorders (Xiangya Hospital, Grant No. 2023LNJJ18).

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This study was approved by the North West Multi-Centre Research Ethics Committee (Reference: 11/NW/0382). All participants provided written informed consent prior to participation.

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The data supporting the findings of this study were obtained from the UK Biobank Resource under Application No. 107175. These data can be accessed by submitting an application through the UK Biobank official website (www.ukbiobank.ac.uk).