South Korean scientists conducted a national cohort study and concluded that antibiotic use during pregnancy and infancy does not increase the risk of developing autoimmune diseases later in life. The study was published in the journal PLOS Medicine.
In recent decades, there has been a rise in the incidence of autoimmune diseases, particularly among children. This trend has been observed worldwide, but the extent of the increase varies depending on genetic predisposition, environmental factors, and healthcare approaches. It has been suggested that the widespread use of antibacterial drugs may play a significant role, as their direct action can disrupt the composition of the microbiota and the development of the immune system. Research on this topic has yielded mixed results, possibly due to the difficulty of accounting for the influence of infections and heredity.
Ju-Young Shin of Sungkyunkwan University and colleagues analyzed data from the Korean National Health Insurance Service for 2008–2021 on children born between April 1, 2009, and December 31, 2020. The analysis included more than 1.5 million children exposed to antibiotics in utero and nearly 1.2 million who were not, as well as nearly 2 million who received these drugs in infancy and more than 1.4 million who were not. Patients exposed and unexposed to antibiotics were compared using inverse probability weighting (IPTW), which, in the absence of randomization, minimizes the influence of confounding factors and reduces biases associated with non-random treatment assignment. The authors also performed a separate analysis among siblings to minimize the influence of familial factors. The association of antibiotic use with the development of six common autoimmune diseases was assessed using Cox proportional hazards models.
Analysis of prenatal antibiotic exposure did not reveal a significant association with the development of type 1 diabetes mellitus (p = 0.132), juvenile idiopathic arthritis (p = 0.83), ulcerative colitis (p = 0.895), Crohn's disease (p = 0.076), systemic lupus erythematosus (p = 0.053), and Hashimoto's thyroiditis (p = 0.448). Analysis of antibiotic exposure in infancy also did not reveal a similar association (p = 0.594; 0.253; 0.776; 0.403; 0.087, and 0.104, respectively). Narrowing the analysis to siblings yielded similar results. Subgroup analyses showed that maternal antibiotic use in the first and second trimesters of pregnancy was associated with a small increased risk of Crohn's disease, while antibiotic use in male infants or during the first two months of life was associated with a small increased risk of Hashimoto's thyroiditis.
Thus, the large, long-term study did not confirm a link between antibiotic exposure in utero and infancy and the development of autoimmune diseases. Risks specific to certain patient subgroups merit further study, the study's authors conclude.
Previous studies have linked antibiotic use in the first years of life with an increased risk of asthma, allergic rhinitis, atopic dermatitis, celiac disease, obesity, and attention deficit hyperactivity disorder, and with stunted growth in boys in the first month of life.
