Phthalate Exposure and Oxidative/Nitrosative Stress in Childhood Asthma: A Nested Case-Control Study with Propensity Score Matching

Jung-Wei Chang; Hsin-Chang Chen; Heng-Zhao Hu; Wan-Ting Chang; Po-Chin Huang; I-Jen Wang

doi:10.3390/biomedicines10061438

Phthalate Exposure and Oxidative/Nitrosative Stress in Childhood Asthma: A Nested Case-Control Study with Propensity Score Matching

Biomedicines. 2022 Jun 17;10(6):1438. doi: 10.3390/biomedicines10061438.

Authors

Jung-Wei Chang¹, Hsin-Chang Chen², Heng-Zhao Hu¹, Wan-Ting Chang³, Po-Chin Huang^{3

4

5

6}, I-Jen Wang^{1

3

7

8}

Affiliations

¹ Institute of Environmental and Occupational Health Sciences, School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan.
² Department of Chemistry, Tunghai University, Taichung 407224, Taiwan.
³ National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli 35042, Taiwan.
⁴ Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 406040, Taiwan.
⁵ Department of Safety, Health and Environmental Engineering, National United University, Miaoli 36003, Taiwan.
⁶ Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
⁷ Department of Pediatrics, Taipei Hospital, Ministry of Health and Welfare, Taipei 10341, Taiwan.
⁸ College of Public Health, China Medical University, Taichung 406040, Taiwan.

Abstract

Whether low-dose phthalate exposure triggers asthma among children, and its underlying mechanisms, remain debatable. Here, we evaluated the individual and mixed effects of low-dose phthalate exposure on children with asthma and five (oxidative/nitrosative stress/lipid peroxidation) mechanistic biomarkers-8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO₂Gua), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-isoprostaglandin F2α (8-isoPF2α), and malondialdehyde (MDA)-using a propensity score-matched case-control study (case vs. control = 41 vs. 111). The median monobenzyl phthalate (MBzP) concentrations in the case group were significantly higher than those in the control group (3.94 vs. 2.52 ng/mL, p = 0.02), indicating that dust could be an important source. After adjustment for confounders, the associations of high monomethyl phthalate (MMP) (75th percentile) with 8-NO₂Gua (adjusted odds ratio (aOR): 2.66, 95% confidence interval (CI): 1.03-6.92) and 8-isoPF2α (aOR: 4.04, 95% CI: 1.51-10.8) and the associations of mono-iso-butyl phthalate (MiBP) with 8-isoPF2α (aOR: 2.96, 95% CI: 1.13-7.79) were observed. Weighted quantile sum regression revealed that MBzP contributed more than half of the association (56.8%), followed by MiBP (26.6%) and mono-iso-nonyl phthalate (MiNP) (8.77%). Our findings supported the adjuvant effect of phthalates in enhancing the immune system response.

Keywords: asthma; oxidative stress; phthalates; propensity score matching.

Abstract

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