Folic Acid Fortification Reduces Congenital Heart Defect Risk NEW YORK (Reuters Health) -Fortifying food with folic acid reduces the risk of certain nonchromosomal congenital heart defects (CHDs), according to new findings published in Circulation.The prevalence of nonchromosomal CHDs fell 11% after Canada introduced folic acid food fortification in 1998, Dr. K.S. Joseph of the University of British Columbia in Vancouver and colleagues reported online August 29.
The findings underscore the importance of folic acid supplementation during the periconceptional period, Dr. Joseph told Reuters Health in a telephone interview. "All women who could get pregnant should be taking folic acid routinely," he said.
Neural tube defects fell by nearly 50% after Canada made folic acid fortification mandatory in 1998. While there is some evidence folic acid fortification has reduced nonchromosomal CHDs as well, Dr. Joseph and colleagues note, these studies didn't account for the effect of changes over time in known CHD risk factors.
In the new study, the investigators looked at all live births and stillbirths at 20 weeks' gestation or later, including late-pregnancy terminations, in Canada (except Quebec and Manitoba) from 1990-2011. They controlled for changes over time in maternal age, prepregnancy diabetes mellitus, preterm preeclampsia, multiple birth and pregnancy termination. There were nearly 6 million births, stillbirths and pregnancy terminations, including 72,591 cases of CHD diagnosed at birth and during infancy. Their analysis focused on 66,980 cases of nonchromosomal CHD.
Overall, there were 12.3 CHDs per 1,000 births. Supplementation was associated with a reduction in conotruncal defects (adjusted rate ratio 0.73), coarctation of the aorta (aRR 0.77), ventricular septal defects (aRR 0.85) and atrial septal defects (aRR 0.81).
However, there was no significant reduction in nonconotruncal heart defects or other heart and circulatory system abnormalities.
"Although food fortification with folic acid was aimed primarily at reducing neural tube defects, this population-based intervention may also have had a beneficial effect on specific types of CHDs, which in aggregate are more common," Dr. Joseph and colleagues conclude.
The study was done under the auspices of the Canadian Perinatal Surveillance System of the Public Health Agency of Canada.