[Association of serum 25(OH)D₃ with cardiovascular risk-related indicators: cross-sectional analysis of NHANES]

This study investigated the association between serum 25(OH)D₃ levels and cardiovascular risk-related indicators. 4 727 participants aged 20 and above from the National Health and Nutrition Examination Survey 2015-2018 database were enrolled. Body mass index, hypersensitive C-reactive protein, high density lipoprotein cholesterol, systolic blood pressure, waist-height ratio, and total cholesterol were selected as the research indicators. Weighted multiple linear regression models, subgroup analyses, smooth curve fitting, and saturation threshold effect analyses were employed to explore the relationship between serum 25(OH)D₃ and these indicators. The results showed that after full adjustment for covariates, every 1 nmol/L increase in serum 25(OH)D₃, the changes in β (95%CI) values for body mass index(BMI), hypersensitive C-reactive protein(hs-CRP), systolic blood pressure(SBP), waist-height ratio(WHtR), high density lipoprotein cholesterol(HDL-C), and total cholesterol(TC) were -0.05 (-0.06, -0.04) kg/m², -0.01 (-0.02, -0.01) mg/L, -0.02 (-0.04, -0.01) mmHg, -0.000 7 (-0.000 8, -0.000 6), 0.10 (0.08, 0.11) mg/dl, and 0.08 (0.04, 0.12) mg/dl, respectively. Female participants were more sensitive to changes in serum 25(OH)D₃, while participants aged 60 and above were relatively less sensitive. The relationship between serum 25(OH)D₃ and these indicators partially exhibited nonlinear patterns across different gender and age subgroups. The saturation threshold effect analysis revealed 8 meaningful inflection points. In summary, vitamin D has a close association with cardiovascular risk-related indicators.