Maternal hypothyroidism closely related with Cardiovascular Diseases in Offspring: Study

Maternal hypothyroidism is associated with an increased risk of CVD in offspring, according to a new study led by Maohua Miao and colleagues. Thyroid hormone deficiency during pregnancy may play a significant role in the observed associations; however, the effects of a shared genetic background and time-stable familial environment/ lifestyle factors cannot be ruled out.

The findings of this study were published in Frontiers in Endocrinology.

No previous research has looked at the impact of maternal hypothyroidism on a wide range of CVD endpoints in the offspring. This study was conducted with the objective to investigate the relationship between maternal hypothyroidism and the risk of CVD in offspring using Danish registry data.

A nationwide population-based cohort study was conducted using the linkage of several Danish national registries to investigate whether maternal hypothyroidism is associated with CVD in offspring. From the age of 8 years to the 31st of December 2016, 1,041,448 singletons born between the 1st of January 1978 and the 31st of December 1998 were studied. The exposure was a maternal diagnosis of hypothyroidism over the course of her life, and the outcome of interest was a CVD diagnosis in her offspring. The CVD hazard ratios (HRs) were estimated using Cox regression models.

The results stated as follow:

1. Offspring born to hypothyroid mothers had an increased risk of CVD and several subtypes of CVD, including hypertension, arrhythmia, and acute myocardial infarction.

2. The magnitude of the association was greatest when the exposure occurred during pregnancy, and this was consistent across all subgroup analyses, including sibling analysis.

3. Notably, there was a weaker association among offspring born to fathers who had hypothyroidism throughout their lives, as well as mothers who developed hypothyroidism more than five years after delivery.

4. The findings of this study add to the evidence that maternal hypothyroidism is associated with a broader spectrum of CVD in offspring than hypertension.

In conclusion, maternal hypothyroidism may have a negative impact on the cardiovascular health of her offspring from adolescence to mid-adulthood, especially if it occurs during pregnancy. Because of the associations observed for paternal hypothyroidism as well as maternal exposure more than 5 years after delivery, the effects of genetic susceptibility or common familial environmental factors cannot be completely ruled out.

Reference:

Miao, M., Liu, H., Yuan, W., Madsen, N., Yu, Y., László, K. D., Liang, H., Ji, H., & Li, J. (2021). Association of Maternal Hypothyroidism With Cardiovascular Diseases in the Offspring. In Frontiers in Endocrinology (Vol. 12). Frontiers Media SA. https://doi.org/10.3389/fendo.2021.739629