Association between dietary folate intake and severe abdominal aorta calcification in adults: A cross-sectional analysis of the national health and nutrition examination survey

Background Prior studies have established a connection between folate intake and cardiovascular disease (CVD). Abdominal aortic calcification (AAC) has been introduced as a good predictor of CVD events, but no previous study has investigated the relationship between dietary folate intake and severe AAC. Therefore, the study aims to explore the association between dietary folate intake and severe AAC in the United States (US) middle-aged and elderly population. Methods This study employed cross-sectional data from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) to examine the relationship between dietary folate intake and severe AAC. Two 24-h dietary recall interviews were conducted to assess dietary folate intake and its sources, while a DXA scan was used to determine the AAC score. To analyze the association between dietary folate intake and severe AAC, a multivariable logistic regression model was applied, and a subgroup analysis was performed. Results Our analysis utilized data from 2640 participants aged 40 years and above, including 288 individuals diagnosed with severe AAC. After adjusting for confounding factors, we observed an inverted L-shaped association between folate intake and severe AAC. Upon further adjustment for specific confounding factors and covariates, the multivariable-adjusted odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the second, third, and fourth quartiles of folate intake, using the first quartile as the reference, were as follows: 1.24 (0.86-1.79), 0.86 (0.58-1.27), and 0.63 (0.41-0.97), respectively. Subgroup analysis results were consistent with the logistic regression models, indicating concordant findings. Moreover, no significant interaction was observed in the subgroup analyses. Conclusions The study findings suggest an inverted L-shaped association between dietary folate intake and severe AAC. However, additional prospective investigations are necessary to explore the impact of dietary folate intake on severe AAC in patients.