A cohort study from California described the importance of extended observation of atopic eczema beyond childhood to reveal clear subtypes based on patterns of disease activity.

Nearly 20% of children in industrialized settings are affected with atopic eczema with different disease patterns. However, recent researches have demonstrated its prevalence to be about 7%-10% in the adult population as well.

Abuabara K. et al reported a lack of prospective studies that examine the course of atopic eczema beyond adolescence and thus they examined the association of early-life risk factors and characteristics with subtypes of atopic eczema, determined their association with atopic disease and other general midlife health.

Study Design-

• They evaluated 30,905 participants from birth into midlife over a period between 1958 and 2016.
• They utilized Latent class analysis (LCA) to identify subtypes of atopic eczema activity patterns.
• Utilizing the data, they examined associations between early life factors and the newly identified atopic eczema subtypes, which were considered categorical outcomes in multinomial logistic regression models, while early-life factors were selected a priori as per previous literature.
• Association of atopic eczema subtype with binary outcomes of self-reported asthma, hay fever, general health, and mental health was examined in separate multivariable logistic regression models adjusted for sex, ethnicity, social class, and cohort.
• Scoring ranging from 1 to 100, was rendered to the 5 questions regarding general health, with higher scores indicating a more positive self-assessment of health.
• A sensitivity analysis was also performed.

The observations of the study were as follows-

• 4 distinct disease trajectories were identified based on the probability of reporting atopic eczema with age.
• The disease trajectories were- 

o Most people reporting no atopic eczema or reporting it rarely,

o Decreasing probability,

o High probability,

o Increasing probability of reporting atopic eczema with age.

• Disease trajectory subtype differed according to the previous early life risk factors such as sex, residence, parental social class, in utero smoke, and breastfeeding.
• Residents of Central England than Southern England, showed an increased risk of the high subtype, along with female sex and lower childhood social class.
• A newly identified subtype was found that had an increased probability of activity in adulthood and had an association with poor self-reported physical and mental health in midlife.

Thus the researchers favored the extended observation of atopic disease beyond childhood, as clear subtypes of atopic eczema based on patterns of disease activity were found in the study.

Additionally, the Early- life factors linked with childhood atopic eczema, provided no differentiation between subtypes, indicating disease trajectory to be modifiable and may be influenced by environmental factors throughout life.

Source: Butera A. Investigators Reveal Subtypes in Atopic Dermatitis Disease Activity, Dermatology Times, 2021.