Maternal Folic Acid Supplementation may mitigate Kawasaki Disease risk in infants, unravels study

In a groundbreaking cohort study conducted by the Japan Environment and Children's Study, researchers have discovered a potential link between maternal folic acid levels and the onset of Kawasaki disease in infants. The study found that the quantity and timing of folic acid supplementation plays a pivotal role in mitigating the risk of Kawasaki disease in infants.

The study results were published in the journal JAMA Network Open.

Kawasaki disease is a form of acute systemic vasculitis primarily observed in infants and young children. Despite extensive research, definitive risk factors for this condition remain elusive. However, there has been previous speculation about a potential link between maternal folic acid supplementation and the occurrence of Kawasaki disease. Hence, researchers conducted a study to investigate the associations of exposure to maternal serum folic acid levels and maternal folic acid supplementation with the onset of Kawasaki disease during infancy among offspring.

The study, utilizing data from a nationwide birth cohort since 2011, analyzed information from 87,702 children followed up to 12 months of age. Of this population, 336 children were diagnosed with Kawasaki disease. The key focus of the investigation was on maternal serum folic acid levels during the second and third trimesters and the frequency of folic acid supplementation during the entire pregnancy. The primary outcome was to measure the onset of Kawasaki disease in offspring up to age 12 months.

Findings:

• Mothers who took folic acid supplements, accounting for 35.7% of the study population with a mean age of 32 years, exhibited higher serum folic acid levels compared to non-supplementing counterparts.
• Strikingly, the study found that higher maternal serum folic acid levels (≥10 ng/mL) were associated with a significantly lower risk of Kawasaki disease in offspring compared to lower levels (0.27% vs 0.41%; Odds Ratio [OR] 0.68).
• The findings also pointed to the timing of maternal folic acid supplementation.
• While supplementation during the first trimester showed a trend toward a lower prevalence of Kawasaki disease, the results were not statistically significant (0.34% vs 0.42%; OR 0.83; 95% CI 0.66-1.04).
• However, supplementation during the second and third trimesters demonstrated a significant reduction in the risk of Kawasaki disease (0.30% vs 0.43%; OR 0.73; 95% CI 0.57-0.94). 
• These results suggest that not only the quantity but also the timing of folic acid supplementation plays a crucial role in mitigating the risk of Kawasaki disease in infants.

The study provides valuable insights into preventive measures for this potentially serious condition. The study contributes to the growing body of evidence on the benefits of folic acid supplementation during pregnancy. With Kawasaki disease affecting a notable number of infants, these findings could have far-reaching implications for maternal healthcare guidelines, emphasizing the need for adequate folic acid intake during specific trimesters to safeguard infant health.

Further reading: Fukuda S, Tanaka S, Kawakami C, Kobayashi T, Ito S, Japan Environment and Children’s Study Group. Maternal Serum Folic Acid Levels and Onset of Kawasaki Disease in Offspring During Infancy. JAMA Netw Open. 2023;6(12):e2349942. doi:10.1001/jamanetworkopen.2023.49942