Additionally, investigators believe epidermal impairment in the skin of children with atopic dermatitis could contribute to the development of allergic sensitization.
A recent study from Denmark suggested that increasing severity of early-onset atopic dermatitis was associated with the development of sensitization to aeroallergens and allergic rhinitis in childhood.
The investigators, led by Hans Bisgaard, MD, DMSc, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, believed their findings called for a randomized controlled trial of early oral exposure to aeroallergens to reduce the risk for developing aeroallergen sensitization and allergic rhinitis in children.
Prior to the study, data indicated that an epidermal barrier impairment in the skin of children with atopic dermatitis was involved with the development of allergic sensitization.
As such, Bisgaard and colleagues used data from the Copenhagen Prospective Studies on Asthma in Childhood2000 (COPSAC2000) at-risk mother-child cohort to determine whether early-onset atopic dermatitis and severity of the disease was associated with development of aeroallergen sensitization and allergic rhinitis at 6, 7, and 12 years of age.
A total of 368 children were included in the study, all of whom were born between August 1998 and December, 2001 to mothers with a history of asthma.
Each child was monitored from birth to 12 years old, with a total of 19 planned visits to the clinic.
Atopic dermatitis in participants was diagnosed at acute care visits from birth to 6 years old according to Hanifin and Rajka’s criteria. The severity of atopic dermatitis was scored using the Scoring Atopic Dermatitis (SCORAD) index at the same visits.
Blood samples were taken from each child to assess sIgE levels at age 6 and 12 years, and allergic rhinitis was diagnosed at age 7 and 12 years based on a parental interviews on history of symptoms in their children.
The investigators assessed allergic rhinitis in 290 (71%) of the 411 children at 7 years, in 353 (86%) children at 12 years and in 368 (90%) children at either 7 and/or 12 years.
Aeroallergen sensitization measured by sIgE (≥ 0.35 kUA/L) at 6 years was present in 29/84 (35%) children with early-onset atopic dermatitis compared to 45/207 (22%) children without early-onset AD.
At 12 years, aeroallergen sensitization was present in 48/89 (54%) vs. 92/215 (43%). Invesitgators found that the GEE model of early-onset atopic dermatitis showed a compiled significantly increased OR for developing aeroallergen sensitization at the two timepoints of 1.68 [1.08; 2.62].
Among children with an early-onset AD, the highest severity score for AD (SCORAD) measured between 0-1 year showed associations with development of aeroallergen sensitization measured by sIgE.
Among children with a late-onset atopic dermatitis, the highest SCORAD measured from 1-6 years showed no significant associations with later development of aeroallergen sensitization.
Bisgaard and colleagues noted thar early-onset atopic dermatitis severity imposed a higher risk for development of sIgE aeroallergen sensitization than late-onset severity.
Despite these findings, the investigators felt that “weaknesses” such as high drop-out rates and lack of compliance led to several limitations in the study. As such, further research was suggested.
“To establish whether early sublingual exposure to aeroallergens can prevent development of sensitization and allergic rhinitis in children with early-onset, severe atopic dermatitis, randomized controlled trials taking all these factors into account are needed,” the team wrote.
The study, “Increasing Severity of Early-Onset Atopic Dermatitis, But Not Late-Onset, Associates with Development of Aeroallergen Sensitization and Allergic Rhinitis in Childhood,” was published online in the European Journal of Allergy and Clinical Immunology.