Prior to the study, little was known on the relationship between the disease and fractures.
An increase in fracture events was recorded in children with atopic dermatitis in a recent study from Korea, in addition to mediating effects such as corticosteroid use and infant feeding practices, the latter of which was said to have “weaker” mediating effects.
Investigators noted that children with atopic dermatitis were prone to multiple risk factors for accidental fractures, which could lead to significant morbidity and mortality.
Despite this, little was known about the relationship between atopic dermatitis and fracture in children.
Kim Ju Hee, MD, Hallym University Kangdong Sacred Heart Hospital, Soul, and fellow investigators examined the association as well as potential mediating factors.
In their nationwide population-based cohort, Hee and colleagues amassed a nationally representative sample of the Korean pediatric population along with their administrative records.
A total of 38,319 children with atopic dermatitis were enrolled in the study alongside 314,721 children without the disease. All children who were enrolled in the study had completed a screening program between the ages of 4 and 6 months.
Information on each participant was taken from the national health insurance service (NHIS) database as well as the national screening program for infants and children (NHSPIC). Atopic dermatitis was defined in each patient according to medical claims and medication prescription records.
Accidental fractures events were investigated between the index date and the end of the follow-up period in a propensity-score-matched-cohort.
A mediation analysis assessed the association of 10 potential factors, which included clinical factors such as the use of antihistamines and systemic corticosteroids as well as social factors such as nutritional status and parental safety awareness.
Finally, investigators performed another mediation analysis to estimate the proportion of association between atopic dermatitis and incident fracture that was attributable to the 10 mediating factors.
The prevalence of fracture events was 21.2% (95% CI: 21.0–21.4) in children without atopic dermatitis and 22.8% in children with atopic dermatitis (95% CI: 22.3–23.3). The median follow-up time for each group was 8.9 years.
Hee and colleagues stated that after adjustment and PS matching for the 38 covariates featured in the study, fracture rates were higher in children with atopic dermatitis relative to those without the disease (aRR: 1.08, 95% CI: 1.05–1.10), and that higher rates were observed in both male and female children.
Regarding risks of fracture, skull and facial bones fractures were deemed significant, while the association for proximal limb fracture was not.
Results were similar in repeated analysis of different age groups, with results showing that 1441 (49%) of participants with atopic dermatitis experiencing fracture during the observation period compared with 5184 (4.5%) of controls.
When outcomes were defined as fracture that occurred after 5≥years, and 1,163 (4.0%) participants of the atopic dermatitis group experienced fracture, compared with 14,456 (12.4%) of those of the controls (aRR 1.07, 95%CI: 1.04–1.11).
Regarding mediating strategies, the duration of systemic corticosteroid prescription was the largest mediating factor, followed by duration of antihistamine prescription, and infant feeding practices.
In particular, the duration of systemic corticosteroid prescription was significantly associated with fracture events (incidence: 20.1% at the 25th percentile and 23.6% at the 75th percentile; difference: 3.4% [95% CI: 2.8–4.0%]).
Investigators found significant evidence supporting higher fracture rates in children with atopic dermatitis, though they could not speak to the prevalence of fractures in older children due to the age limitations featured in the study.
“The individuals in our study were aged 71 months or younger, so the generalizability of our findings to older children is uncertain,” the team wrote.
The study, “Association of clinical and social factors with risk of fracture in children with atopic dermatitis,” was published online in Pediatric Allergy and Immunology.