Infants born to mothers with rheumatoid arthritis (RA) during pregnancy are at risk of autism spectrum disorder (ASD), according to a study.
The study included all children born alive in Sweden from 1995 to 2015, followed up through 2017. Diagnoses of ASD and RA were ascertained using data from the National Patient Register. Cox regression was used to estimate the association between maternal RA and ASD risk in offspring. Researchers also looked at RA serostatus, etiological subgroups and the timing of exposure.
A separate analysis was performed and included a negative control group for RA, arthralgia, with similar symptomology as RA but free from inflammation/autoimmunity.
ASD was diagnosed in 70 of 3,629 children (1.94 percent) born to mothers with RA and in 28,892 of 1,503,908 children (1.92 percent) born to mothers without RA. Maternal RA before delivery was associated with a 43-percent increase in the risk of ASD in offspring (hazard ratio [HR], 1.43, 95 percent [CI], 1.11–1.84). The risk increase was notably greater for seronegative RA (HR, 1.61, 95 percent CI, 1.12–2.30).
There were no similar associations found for paternal RA, maternal sisters with RA, or RA diagnosed after delivery. Meanwhile, like maternal RA, maternal arthralgia also posed high offspring ASD risk (HR, 1.41, 95 percent CI, 1.24–1.60).