Cardiovascular Disease in Offspring Linked to Maternal Hypothyroidism

Babies born to mothers with thyroid hormone insufficiency were found to be at increased risk for cardiovascular disease (CVD). These findings, from a nationwide population-based cohort study, were published in Frontiers in Endocrinology.

Using Danish population-based registries, all singleton births (N=1,041,448) in Denmark between 1978 and 1998 were included in this study. CVD risk was assessed on the basis of maternal hypothyroidism status.

A total of 11,281 children were born to mothers with a diagnosis of hypothyroidism. The hypothyroid and control (n=1,030,167) cohorts comprised 51.0% and 50.6% boys, 4.5% and 3.7% were born preterm, 45.9% and 20.5% of mothers had CVD, 11.9% and 2.6% of mothers had diabetes, and 33.4% and 30.3% of mothers smoked during their first trimester, respectively.

A total of 30,860 of the babies were diagnosed with CVD as adults (incidence rate, 25.9 per 1000 person-years) at a median age at diagnosis of 23.2 (interquartile range [IQR], 18.8-28.5) years.

After adjusting for year of birth, gender, parity, maternal age at birth, education, and employment, babies who were born to mothers with hypothyroidism were at increased risk for CVD (adjusted hazard ratio [aHR], 1.23; 95% confidence interval [CI] 1.12-1.35).

The risk was greatest when the mother was diagnosed with CVD during pregnancy (aHR, 1.71; 95% CI, 1.10-2.67) but remained significant if they received a diagnosis 5 years or more after giving birth and with adjustment for coexisting diseases like neoplasms, circulatory, digestive and genitourinary diseases (aHR, 1.19; 95% CI, 1.04-1.37).

Maternal hypothyroidism associated with the CVD events of acute myocardial infarction (aHR, 2.02; 95% CI, 1.16-3.50), hypertension (aHR, 1.39; 95% CI, 1.14-1.69), and arrhythmia (aHR, 1.22; 95% CI, 1.04-1.44).

In an analysis of matched siblings who were and were not exposed to maternal hypothyroidism, in utero thyroid hormone insufficiency was associated with CVD (aHR, 1.73, 95% CI, 0.96-3.10) and hypertension (aHR, 2.01; 95% CI, 1.20-3.36) risk.

Researchers acknowledged several limitations of the study, including a reliance on patients’ electronic medical records, which may have included incomplete or incorrect information.

“Maternal hypothyroidism may have an adverse effect on offspring’s cardiovascular health from adolescence to mid-adulthood, particularly when the exposure occurs during pregnancy,” the researchers concluded.

Disclosure: This research was supported in part by the Novo Nordisk Foundation. Please see the original reference for more disclosures.

Reference

Miao M, Liu H, Yuan W, et al. Association of maternal hypothyroidism with cardiovascular diseases in the offspring. Front Endocrinol. 2021;12:739629. doi:10.3389/fendo.2021.739629