Abstract
CONTEXT: The association of serum 25-hydroxyvitamin D [25(OH)D] and genetic polymorphisms of the vitamin D receptor (VDR), and the vitamin D binding protein (VDBP) with incident abdominal aortic aneurysm (AAA) remains uncertain.</p>
OBJECTIVE: To investigate whether serum 25(OH)D, genetic polymorphisms of VDR and VDBP, genetic susceptibility to AAA, and the interactions among these factors influence the risk of incident AAA.</p>
DESIGN: Retrospective cohort study.</p>
SETTING: UK Biobank.</p>
PARTICIPANTS: 447,529 participants without a diagnosis of prevalent aortic aneurysm or aortic dissection at baseline.</p>
EXPOSURE: Serum 25(OH)D concentration.</p>
MAIN OUTCOME MEASURE: Incident AAA.</p>
RESULTS: During a median follow-up of 12.5 years, 2,042 participants developed incident AAA. A significant inverse association between serum 25(OH)D and incident AAA was observed (per SD increment, HR, 0.92; 95%CI, 0.88-0.96), which was particularly pronounced in older individuals and those without diabetes (both P for interaction <0.05). Compared to participants with serum 25(OH)D ≥ 50 nmol/L, those with serum 25(OH)D between 25 and <50 nmol/L and <25 nmol/L exhibited a significant higher risk of incident AAA. In the 371,621 participants with genetics assessment, individuals carrying AA alleles of ApaI SNP had a significant increased risk of incident AAA compared to those carrying CC alleles (HR, 1.16; 95%CI, 1.02-1.32). The inverse association between serum 25(OH)D and incident AAA was stronger in individuals with intermediate or high genetic risk for AAA (P for interaction = 0.048).</p>
CONCLUSIONS: There was a significant inverse association between serum 25(OH)D and AAA incidence, particularly among individuals with higher genetic risk for AAA, older age, and without diabetics.</p>