Antidepressants topic of study
By Ariana Eunjung Cha WASHINGTON POST JULY 10, 2015
WASHINGTON — Researchers from the Centers for Disease Control, joining a debate about the use of a class of antidepressants during pregnancy, confirmed a link between birth defects and some drugs but not others.
Their analysis, published in the BMJ on Wednesday, included 17,952 mothers of children born with birth defects and 9,857 mothers of children without birth defects born between 1997 and 2009 at 10 centers. A total of 1,285 reported taking SSRIs, selective serotonin reuptake inhibitors, during one month before conception through the first trimester of pregnancy — the period believed to be the most vulnerable for a fetus.
The drug most commonly used by study participants was Zoloft (sertraline), then Prozac (fluoxetine) and Paxil (paroxetine), Celexa (citalopram), and Lexapro (escitalopram).
Birth defects are alarmingly common, affecting one in every 33 babies born in the United States, but scientists are still in the early stages of determining what causes most of them. Since the Food and Drug Administration issued an advisory warning of a potential association in December 2005 between paroxetine and heart defects in infants, researchers have launched numerous studies to try to confirm the problem but have come to conflicting conclusions.
‘‘[T]he inconsistent reports have limited opportunities for clinicians to carefully evaluate the risk compared with benefit of specific SSRIs for given patient during pregnancy,’’ the researchers wrote.
The new CDC study provides evidence that some SSRIs may be riskier than others.
While previous studies had shown associations between sertraline and five kinds of birth defects, the CDC study was unable to confirm any of them. Jennita Reefhuis, lead author of the study and an epidemiologist in the birth defects branch of the CDC, said in an interview that this was ‘‘reassuring’’ since this was the most commonly used drug among the group studied.
The researchers, however, found reason to be concerned about two other SSRIs, however. Children born to mothers who had taken paroxetine had a higher incidence of anencephaly, in which a baby is born without parts of the brain and skull, as well as defects of the heart and abdominal wall. Fluoxetine was associated with higher incidence of a heart defect and craniosyntosis, a condition that affects one or more of the joints in a baby’s skull.
Reefhuis said while associations were clear, the absolute risk to the babies appeared small. For instance, the risk of anencephaly for children of women who take paroxetine would grow from 2 per 10,000 to 7 per 10,000. ‘‘It is a doubling or more in some cases, but you have to keep in mind that a doubling of small risk is still a small risk,” she said.
She said there were limitations to the study, including the fact that the researchers did not know the dose of the antidepressants taken by the women or why they were taking them.
