Abstract
Background Evidence for the association between maternal thyroxine concentration and the risk of fetal congenital heart defects (CHDs) is absent. We aimed to study the association of maternal free and total thyroxine (FT4 and TT4) concentrations and the free-to-total thyroxine proportion (FTT4P, %) with the risk of CHD. Methods The study was a hospital-based cohort study of 52,047 women who received a universal thyroid function test between 2012 and 2016. CHD was screened by ultrasound between 20 and 24 weeks of gestation or diagnosed until the 42nd day of birth. Adjusted odds ratios (ORs) of fetal CHD were estimated for maternal FT4 and TT4 concentrations or the FTT4P by multivariate logistic regression. Results A total of 41,647 women with singleton pregnancies were included for the analysis and 215 CHD cases were detected. The FT4 concentration was significantly associated with a higher risk of CHDs (OR, 1.04, 95% confidence interval (CI): 1.01 to 1.07). Each 1% higher FTT4P was related to a 1.41-fold (95% CI: 0.27 to 3.59) higher risk of CHDs. The association became stronger for women with a thyroid function test performed between 12 and 18 weeks of gestation (OR = 1.05 (95% CI: 1.01 to 1.09) for the FT4 concentration and 3.32 (95% CI: 1.43 to 7.73) for the FTT4P). Conclusions A higher FT4 concentration or FTT4P, measured between 12 and 18 weeks of gestation, was associated with an increased risk of CHDs. These findings may provide new insights into the mechanisms of CHDs and evidence for clinical decisions related to thyroid function tests.
Highlights
Congenital heart defects (CHDs) are the most common birth defects in newborns and an important cause of infant morbidity and mortality [1]
During the follow-up period, 215 congenital heart defects (CHDs) cases were identified, including 96 newborns diagnosed after birth and 119 fetuses with an ultrasound-suspected CHD. e prevalence of CHD was 5.2 per 1,000 infants, and 2.3 per 1,000 infants for confirmed CHD
Higher free-to-total thyroxine proportion (FTT4P) was related to an increased risk of CHD, with an adjusted odds ratio of 4.34. e association strengths between FTT4P and risk of CHDs were consistent across the multiple imputation groups, with adjusted odds ratios (ORs) ranging from 4.08 to 4.96. e differences in the FT4 concentration and FTT4P between women with and without a CHD offspring got greater when the thyroid function test was performed between 12 and 18 weeks of gestation (Figure S4)
Summary
Congenital heart defects (CHDs) are the most common birth defects in newborns and an important cause of infant morbidity and mortality [1]. Evidence for the association between thyroid dysfunction and the risk of CHD is absent. Evidence for the association between maternal thyroxine concentration and the risk of fetal congenital heart defects (CHDs) is absent. Each 1% higher FTT4P was related to a 1.41-fold (95% CI: 0.27 to 3.59) higher risk of CHDs. e association became stronger for women with a thyroid function test performed between 12 and 18 weeks of gestation (OR 1.05 (95% CI: 1.01 to 1.09) for the FT4 concentration and 3.32 (95% CI: 1.43 to 7.73) for the FTT4P). A higher FT4 concentration or FTT4P, measured between 12 and 18 weeks of gestation, was associated with an increased risk of CHDs. ese findings may provide new insights into the mechanisms of CHDs and evidence for clinical decisions related to thyroid function tests
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
