Phthalate exposure is associated with cardiovascular risk. Among the various phthalates, di-(2-ethylhexyl) phthalate (DEHP) is a deleterious plasticizer in our daily lives. This study investigated the association between DEHP exposure and the alteration of heart rate variability (HRV). During 2017–2019, we recruited 974 young adults to investigate the effects of living environments and dietary habits on cardiometabolic disorders in Taiwan. We quantitatively analyzed urinary metabolites of DHEP. A continuous electrocardiogram was recorded to obtain a 5-min ECG. Time-domain and frequency-domain HRV analyses were performed. Multiple linear regression showed that urinary oxidized DEHP metabolites MEHHP and MEOHP were associated with decreased HRV after controlling for associated cardiovascular risk factors. A higher MEHHP level was associated with a lower triangular interpolation of NN interval histogram (TINN), very low frequency (VLF), and low frequency/high frequency (LF/HF) ratio. A higher MEOHP level was associated with a decreased LF/HF ratio. In addition, trend analysis showed that higher MEHHP and MEOHP quantiles were significantly associated with a decreased LF/HF ratio. DEHP is a potentially harmful and invisible chemical. The urinary DEHP metabolites MEHHP and MEOHP are associated with decreased HRV, indicating an adverse effect on autonomic balance in young adults in Taiwan.

Huang YS, et al. Korean J Radiol. 2023 Mar;24:e23. https://doi.org/10.3348/kjr.2022.0675

Background: Vitamin D has been associated with blood pressure across the life course in observational studies, although effect sizes are generally modest and findings are not fully consistent. We examined the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and multiple blood pressure indices in a community-based cohort of young adults. Methods: We conducted a cross-sectional analysis within the Young Taiwanese Adults (YOTA) cohort, restricting the sample to adults aged 18–45 years with complete serum 25(OH)D and blood pressure data. Serum 25(OH)D was modeled as a continuous variable and additionally examined using predefined concentration categories. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were assessed using standardized protocols. Multivariable linear regression models evaluated associations, with sequential adjustment for demographic, anthropometric, cardiometabolic, and lifestyle covariates. Restricted cubic spline models assessed potential nonlinearity. Results: Among 923 participants, higher serum 25(OH)D concentrations were modestly and linearly associated with lower SBP, DBP, and MAP after multivariable adjustment. Each 10 ng/mL increase in serum 25(OH)D was associated with a 1.07 mmHg lower SBP, a 1.19 mmHg lower DBP, and a 1.22 mmHg lower MAP. Associations remained consistent in sensitivity and subgroup analyses. Conclusions: In young adults, higher serum 25(OH)D concentrations were modestly associated with lower blood pressure indices. These findings confirm prior observational evidence of modest inverse associations between serum 25-hydroxyvitamin D concentrations and blood pressure and extend these observations to a relatively healthy young adult population. Prospective studies are required to clarify temporality and clinical relevance.