Concurrent dietary intake to nitrate, thiocyanate, and perchlorate is negatively associated with hypertension in adults in the USA

We aimed to comprehensively evaluate the association of urinary nitrate, thiocyanate, and perchlorate metabolites with hypertension among a nationally representative sample of the US adult population. This cross-sectional study investigated data from 15,717 adults aged more than 20 years obtained from the National Health and Nutritional Examination Survey (NHANES) for the years 2005-2016. In the survey, urinary levels of nitrate, thiocyanate, and perchlorate were measured using ion chromatography combined with electrospray tandem mass spectrometry. Blood pressure was calculated as the mean of three measurements. Hypertension was defined as (a) systolic BP >= 130 and/or diastolic BP >= 80 mmHg and/or (b) self-report. Multivariate logistic regression and weighted quantile sum (WQS) regression models were applied to estimate the association between exposure to multiple inorganic anions and hypertension. Restricted cubic spline (RCS) regressions were fitted to discern the potential relationship between the anion exposure and hypertension. These innovation methods used to support our results. Overall, 7533 (49.95%) people with and 7638 (50.35%) without hypertension were included in this study. In the multivariable-adjusted logistic regression models, urinary nitrate (P < 0.001) and perchlorate (P < 0.001) were independently negatively associated with increased occurrence of hypertension, while urinary thiocyanate was insignificantly associated with hypertension (P = 0.664). The WQS regression index showed that, in combination, the three inorganic anions mixture were negatively correlated with hypertension (adjusted OR 0.89; 95% CI 0.83-0.95, P < 0.001). Urinary nitrate was the most heavily weighted component in the hypertension model (weight = 0.784). RCS regression demonstrated that nitrate (nonlinearity P = 0.205) and perchlorate (nonlinearity P = 0.701) were linearly associated with decreased occurrence of hypertension. Concurrent exposure to nitrate, thiocyanate, and perchlorate is associated with a decreased risk of hypertension, with the greatest influence coming from nitrate probably; urinary specific thiocyanate alone had an insignificant association with hypertension.