Clinical Relevance of Uric Tobacco-Specific Nitrosamine and Severe Abdominal Aortic Calcification in a National Survey of the United States

Abstract

Background: This cross-sectional study is the first investigation of the relationships among uric tobacco-specific nitrosamine (TSNA), N′-nitrosonornicotine (NNN), and abdominal aortic calcification (AAC) in adults in the United States. Methods: The final sample (2713 participants 40 years of age and older) was obtained from the National Health and Nutrition Examination Survey (NHANES) 2013–2014. The risk of severe AAC according to uric NNN, the dose–response relationship between uric NNN and severe AAC, and the threshold effect were analyzed with multivariate logistic regression models, a cubic spline model, and a two-piecewise linear regression model, respectively. Results: In the fully adjusted model, the odds ratio (and 95% confidence interval) of severe AAC for participants in the high uric NNN group with respect to the low uric NNN group was 2.39 (1.59–3.61) (P < 0.001). After adjustment for multiple covariates, the risk of severe AAC increased 1.515-fold for every 1 ng/dL increase in uric NNN when the concentration of uric NNN was below 1.354 ng/dL. The association between uric NNN and severe AAC was stable among various subgroups. Conclusion: In a sample of United States civilians, uric NNN levels positively correlated with the risk of severe AAC.