Lisolette Brydensholt Halkjaer, MD, and colleagues report the news in the Archives of Dermatology. Halkjaer works in Denmark at the Danish Pediatric Asthma Centre of Copenhagen University Hospital.
Atopic dermatitis (AD) is the most common form of eczema. In eczema, the skin is inflamed or irritated. "Atopic" diseases are often inherited and may go along with other allergic conditions, such as asthma and hay fever.
Halkjaer's study included 356 white babies in Copenhagen, Denmark, whose mothers had a history of asthma. Atopic dermatitis was diagnosed in 44% of the kids by the time they were 3 years old.
Early Warning Sign
The study shows that babies who had had rashes on their arms and joints by 18 months were more likely to develop atopic dermatitis by the time they were 3 years old.
Infants' diaper rash and cheek rashes didn't predict atopic dermatitis, the study shows.
"These observations may be useful for early prediction of AD," the researchers write.
When atopic dermatitis developed, it typically started at the scalp, forehead, ear, neck, and cheek, later spreading to the arms, legs, and other parts of the face and body. Most cases were mild to moderate, according to the study.
Almost 80% of the kids with atopic dermatitis had had itchy cheek rashes. So had more than 40% of kids not diagnosed with atopic dermatitis.
"While the cheeks were the most commonly involved region in children who later developed AD, involvement with this region was also common in children who did not develop AD," the researchers write. They add that "skin lesions on the cheek are not specific for atopic dermatitis."
Earliest Reported Sign
In the study, the earliest sign of dermatitis was recorded for a 1-month-old baby. The highest incidence rate happened in the second six months of life.
Prevalence of atopic dermatitis peaked when boys were 2 years old and when girls were 2-and-a-half years old.
Remember, the babies that were studied may have been at higher risk of atopic dermatitis due to their mothers' history of asthma and atopic dermatitis. It's not clear if the results apply to babies whose mother's do not have these conditions.
The study's funding sources included the drug companies AstraZeneca, LEOpharma, Yamanouchi Pharma, and Pharmacia-Pfizer.
One of the researchers -- Hans Bisgaard, MD, DMSci, who works at Copenhagen University Hospital -- reports consulting, receiving lecturers' fees, or holding sponsored grants from the drug companies AstraZeneca, Altana, GlaxoSmithKline, MedImmune, and Merck. Those financial disclosures are listed in the journal.