Phenotypical Differences of Childhood- and Adult-Onset Atopic Dermatitis.

BACKGROUND

Little is known about adult-onset atopic dermatitis (AD).

OBJECTIVE

To determine the associations and clinical characteristics of adult-onset AD.

METHODS

A prospective study of 356 adults with AD (age ≥18 years) was performed using standardized questionnaires and examination. AD severity was assessed using the Patient-Oriented Eczema Measure, Eczema Area and Severity Index, Scoring Atopic Dermatitis, body surface area, and numeric rating scale for itch and sleeplessness. Latent class analysis was used to determine dominant clinical phenotypes. Multivariate logistic regression was used to determine the relationship between adult-onset AD and distinct phenotypes.

RESULTS

One hundred forty-nine adults (41.9%) reported onset of AD during adulthood, with 87 (24.4%) after the age of 50 years. Adult- versus childhood-onset AD was associated with birthplace outside the United States (χ2, P = .0008), but not sex, race/ethnicity, current smoking status, or alcohol consumption (P ≥ .11); and decreased personal history of asthma, hay fever, and food allergy and family history of asthma and food allergy (P ≤ .0001 for all). There was no significant difference in the Eczema Area and Severity Index, Scoring Atopic Dermatitis, body surface area, numeric rating scale for itch and sleeplessness, or Patient-Oriented Eczema Measure between adult- and childhood-onset AD (Mann-Whitney U test, P ≥ .10). Latent class analysis identified 3 classes: (1) high probability of flexural dermatitis and xerosis with intermediate to high probabilities of head, neck, and hand dermatitis; (2) high probability of flexural dermatitis and xerosis, but low probabilities of head, neck, and hand dermatitis; and (3) lower probability of flexural dermatitis, but the highest probabilities of virtually all other signs and symptoms. Adult-onset AD was significantly associated with class 1 (multivariate logistic regression; adjusted odds ratio, 5.54; 95% CI, 1.59-19.28) and class 3 (adjusted odds ratio, 14.03; 95% CI, 2.33-85.50).

CONCLUSIONS

Self-reported adult-onset AD is common and has distinct phenotypes with lesional predilection for the hands and/or head/neck.