Inflammation during pregnancy may increase asthma risk in offspring

PHOENIX — Elevated C-reactive protein levels, a marker of inflammation, in early and late pregnancy may increase risk for asthma in offspring, according to a study presented here.

Yih-Chieh Chen, MD, a third-year fellow in allergy and immunology at Brigham and Women's Hospital, and colleagues sought to research the hypothesis that certain prenatal factors may influence childhood asthma risk in offspring. Their findings were presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting.

“I am interested in the prenatal factors that may be associated with offspring allergic disease to see if there are any modifiable factors even in utero that can modify offspring asthma risk,” Chen told Healio.

Yih-Chieh Chen

Chen and colleagues used data from the Vitamin D Antenatal Asthma Reduction Trial birth cohort to evaluate 523 maternal-offspring pairs. Researchers collected maternal prenatal plasma C-reactive protein (CRP) measurements in the first and third trimesters, and they genotyped two single nucleotide polymorphisms (SNPs) — rs1417938 and rs1205 — that are associated with increased CRP.

The researchers also evaluated parental reports of physician-diagnosed asthma, eczema and allergic rhinitis from birth until 6 years of age.

Overall, researchers identified a greater risk for childhood asthma associated with elevated CRP in the first (OR = 1.26; 95% CI, 1.04-1.54) and third (OR = 1.52; 95% CI, 1.22-1.91) trimesters.

Also, an increase in CRP that occurred from the first to the third trimester also correlated with increased childhood asthma (OR = 2.27; 95% CI, 1.4-3.71).

“The big picture is that maternal health is really important for offspring health,” Chen said. “On a cellular/molecular level, increased CRP may be driving development of type 2 inflammation, because CRP has been shown to do this in other studies.”

Although researchers confirmed that rs1417938 and rs1205 SNPs were linked to CRP levels, they did not predict childhood asthma risk.

Acknowledging these results, Chen said there may be steps women trying to conceive can take to reduce their inflammation and thus offspring asthma risk.

“Try to have a healthy pre-pregnancy BMI, a diet heavy in fruits and vegetables, quit smoking and get your asthma under control,” Chen said, adding that obesity, a diet rich in fried foods or red meat, smoking and asthma are all factors that increase inflammation.

“I am now examining how prenatal factors and close postnatal factors might affect the gut microbiome and asthma risk in offspring,” she added.