Higher folic acid levels during pregnancy may help prevent Kawasaki disease in newborns

Having greater serum folic acid levels and taking folic acid supplements more than once a week during the second and third trimesters appear to lower the risk of Kawasaki disease among infants, according to a study.

For the study, researchers used data from the Japan Environment and Children’s Study. They analysed maternal serum folic acid levels (≥10 ng/mL classified as exposed) and the frequency of maternal folic acid supplementation during pregnancy in relation to the onset of Kawasaki disease in offspring up to age 12 months.

The analysis included a total of 87,702 children who were followed-up for 12 months. Of these children, 336 had Kawasaki disease. Meanwhile, mothers who took folic acid supplements during pregnancy (n=31,275 [35.7 percent], mean age 32 years) had higher serum folic acid levels compared with those who did not take supplements.

In propensity score–adjusted logistic regression models, higher maternal serum folic acid levels were associated with a significant protection against the risk of Kawasaki disease in offspring (≥10 vs <10 ng/mL; odds ratio [OR], 0.68, 95 percent confidence interval [CI], 0.50–0.92).

The prevalence of Kawasaki disease was lower among children whose mothers took folic acid supplements during the first trimester than among those who mothers did not take the supplements (0.34 percent vs 0.42 percent), although the difference did not reach significance (OR, 0.83, 95 percent CI, 0.66–1.04).

Compared with no supplementation, supplementation during the second and third trimesters was associated with a 27-percent reduction in the risk of Kawasaki disease (0.30 percent vs 0.43 percent; OR, 0.73, 95 percent CI, 0.57–0.94).