Indoor Exposure to Phthalates and Hypertension in the NHANES Data 2017- 2018

Abstract

Title: Indoor Exposure to Phthalates and Hypertension in the NHANES Data 2017- 2018 Introduction: Hypertension (HT) is a common chronic disease with high prevalence worldwide, in the Arab world and in Lebanon, and is a major contributor to premature death. One of the emerging environmental potential risk factors for HT is the indoor exposure to everyday plastic products containing phthalates. However, the association of phthalates with HT is still controversial. The objective of this study is to examine if this association exists and what factors may modify it. Methods: The study followed a cross-sectional design using secondary data from national US NHANES 2017- 2018 population-based surveys. Multi-stage random sampling was used in this dataset. The data was collected through interviews using questionnaires. The sample size in this analysis was 1,857 participants age ≥ 20 years who had provided urinary specimens in which phthalates’ concentrations were measured. Eight phthalate metabolites are used in this analysis which form low-molecular and high molecular phthalates. Bivariate and multivariate logistic regression were performed to study the association, along with other covariates. A final best-fit model was later analyzed. Results: At the time of the survey, 37% of the participants had HT. When phthalate monoesters were analyzed separately, an association between mono-ethyl phthalate (MEP) and HT was present (OR=1.01, 95% CI: 1.003- 1.02) at the bivariate level. Other covariates that were statistically significant with HT in the multivariate logistic regression were age, race and BMI. Discussion: The results of this analysis are consistent with other studies showing no association between phthalates and HT at all, and studies showing no association for MEP in specific. The results of this study can be used to evaluate the trend of association between phthalate metabolites and HT across years, since prior studies have used the NHANES datasets of different years resulting in different monoesters being associated with HT. Conclusion: More cohort longitudinal studies should be done to better understand the association between phthalates and HT, as results are not consistent in the literature. Based on this analysis, known and preventable risk factors for HT should be screened and controlled to reduce the additive risk of phthalate on the risk of HT. These may include lowering the BMI to reduce the odds of having HT.