SSRI Birth Defect Study Could be Misleading

Boston, MAWhile new research appears to excuse selective serotonin reuptake inhibitors (SSRI) antidepressants from concern over SSRI birth defects, the authors of previous studies raising concerns about potential birth defects noted a key component of the study that could be construed as misleading.

According to Parents (1/3/13), a study of 1.6 million women residing in Nordic countries exhibited a higher rate of stillbirth and infant death on behalf of study participants who took SSRI antidepressants while pregnant, against those participants who did not. However, research authors were quick to qualify that risk of SSRI side effects as stemming from factors other than SSRI drugs.

Dr. Olaf Stephansson told the Huffington Post that the increase in SSRI birth defects was due to “an increased proportion of smokers, older [maternal] age, diabetes and hypertensive disease.”

The clinical epidemiologist with Karolinska University Hospital in Sweden maintained the increased risks in SSRI Side Effects were attributable to the aforementioned risk factors, “and not the medication.”

But not so fast, says Dr. Adam Urato, the chair of Obstetrics and Gynecology at MetroWest Medical Center in Massachusetts. In comments to the Huffington Post, Dr. Urato noted the study focused on dispensed drugs as opposed to ingested drugs, “and these numbers are often quite different,” he said.

According to Parents, data used in the study were gleaned from prescription registries, together with patient and birth registries in Denmark, Finland, Iceland, Norway and Sweden. And the choice of data has its supporters??"among them Dr. Katherine Moore, assistant professor of psychiatry with the Mayo Clinic. "This data is some of the best in the world [for] doing population-based research," she said, in comments published in Parents. "It integrates data from multiple sources: out-patient and in-patient, pharmacy records. This study offers additional evidence supporting the safety of SSRI use in pregnancy."

But that doesn’t placate Dr. Urato, who himself was an author on an earlier study published in November in Human Reproduction that found women who ingest SSRI drugs while pregnant may have a greater risk of complications including birth defects such as PPHN (persistent pulmonary hypertension of the newborn), premature birth and miscarriage.

Looking at dispensed drugs v. ingested selective serotonin reuptake inhibitors, noted Dr. Urato, could result in a woman being incorrectly classified as taking an SSRI (and having a good outcome), whereas in actual fact the woman may have belonged to the group classified as not taking an SSRI.

"When exposure information is inexact the result is often that we do not find evidence of harm from a drug," Urato added.

It should be noted the most recent study was funded, in part, by the Swedish Pharmacy Company and published in the Journal of the American Medical Association (JAMA). And while the study authors concluded that SSRI birth defects did not pose any significant risk, they referenced previous studies that nonetheless found a risk of SSRI side effects and stressed that decisions covering treatment options need to take into account other potential and unforeseen outcomes.

"Previous studies have found an increased risk for congenital cardiac malformations for Paroxetine [known by trade names like Paxil] and a modest risk increase for persistent pulmonary hypertension [PPHN] among newborns," Stephansson said.

The stakes are high. Antidepressant use in the US is at an all time high, and selective serotonin reuptake inhibitors are extremely popular. A 2009 joint report from the American College of Obstetricians and Gynecologists and the American Psychiatric Association found that up to 23 percent of women have at least one depressive episode while pregnant.

That report stressed that women battling severe depression should continue taking medication. However, the same report recommended against antidepressant use for women experiencing mild symptoms of depression.

Many an SSRI lawsuit has claimed that women having experienced the guilt and heartbreak of SSRI birth defects were not aware of the risks. It doesn’t help that some studies articulate those risks, whereas others do not--leaving the debate wide open and many say, unwinnable.

There is no question that depression is an ongoing concern in the US, and selective serotonin reuptake inhibitors are effective in managing depression. However the risk for SSRI birth defects and the debate surrounding SSRI use while pregnant takes on an added dimension when the life of the unborn child--who has no say in the matter--could be adversely affected.