Genetics May Play Role In Antidepressant Birth Defect Risks: Study

Amid mounting concerns about the risk of birth defects from antidepressants like Zoloft, Paxil and other widely used drugs, the findings of a new study suggest that genetics may play an important role.

In findings published earlier this month in the medical journal The BMJ, researchers from the University of Arkansas indicate that some common genetic variants could significantly increase the risk of birth defects linked to a class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs), which include some of the most widely used drugs in the United States.

SSRI antidepressants are prescribed to up to 10.2% of pregnant women, despite prior research that suggests some of the medications may increase the risk of birth defects, miscarriage, autism, and other problems when used during pregnancy.

“Epidemiologic studies have produced inconsistent results regarding the impact of maternal use of SSRIs during embryogenesis,” the researchers noted. “Some studies have reported an increased risk of congenital heart defects, while others report no association.”

In this latest study, researchers found that genetic variants commonly found in mothers and infants could play a role, increasing the risk of birth defects associated with SSRIs.

The population-based study looked at DNA from parents, and infants and also looked at data on 1,180 infants born with congenital heart defects, as well as 1,644 controls, born between 1997 and 2008. They identified three metabolic pathways that appeared to increase the risk of congenital heart defects, including folate, homocysteine and glutathione/transsulfuration pathways.

The antidepressants Zoloft, Prozac and Paxil were the most commonly used among mothers included in the study.

The findings suggest that when SSRIs were taken, some maternal genotype variants increased the risk of congenital birth defects from 2.4 to 5.9 times over those without those genotypes.

“Our results provide initial evidence of a modifying effect of common maternal and infant variants in genes that encode for critical enzymes in the folate, homocysteine, and glutathione/transulfuration pathways on the association between maternal periconceptional SSRI use and risk of congenital heart defects in their offspring,” the researchers concluded. “Given the widespread use of SSRIs among women for various conditions, further exploration is warranted of the complex association between risk of congenital heart defects and folate supplementation, periconceptional SSRI use, and variants in folate, homocysteine, and glutathione/transsulfuration pathways among women with psychiatric illness.”

Antidepressant Pregnancy Concerns

This research is the latest in a series of studies that highlight potential concerns surrounding pregnancy use of antidepressants.

In a study published last year in the medical journal Pediatrics, researchers from Johns Hopkins also found a link between the use of SSRIs during pregnancy and autism in boys. That study found the risk effectively tripled. However, research into the association has turned up inconsistent results.

In November 2013, a study published in the medical journal Clinical Epidemiology raised questions on whether there was an actual association between autism and SSRIs. The Danish researchers who conducted that study found no such link after looking at data on more than 600,000 children.

However, the Danish findings contradicted a study published in April in the British Medical Journal, which indicated that there is a link between parental depression, antidepressant use and the risk of autism. That study, which looked at 4,429 cases of autism and more than 40,000 controls, finding that women who took any antidepressant while pregnant were about twice as likely to give birth to a child that would later test on the autism spectrum.

In July 2011, researchers from Kaiser Permanente reported that the use of SSRI antidepressants while pregnant was linked to twice the risk of giving birth to an autistic child.

In addition to autism, many popular antidepressants have been linked to a risk of serious health problems for children exposed to the medication before birth, including septal heart defects, skull malformations, neural tube defects, abdominal defects, spina bifida and other serious injuries.

Recent studies have also found that antidepressant use in pregnancy may increase the risk of seizure problems and delay infant development milestones, such as sitting and walking are affected by antidepressant use during pregnancy.

Pregnancy antidepressant risks have also been linked to a serious respiratory disorder, known as persistent pulmonary hypertension in newborns (PPHN), which may cause insufficient blood flow to the lungs, leading to serious and potentially life-threatening problems.

In recent years, a growing number of Zoloft lawsuits and Paxil lawsuits have been filed in courts throughout the United States on behalf of children born with defects and malformations after exposure to the medication during pregnancy.

The complaints allege that the manufacturers of the medications failed to adequately research the risks associated with use of the antidepressant in pregnancy, or provide proper warnings to women about the risk of becoming pregnant while using the medication.