Risk of atopic dermatitis and the atopic march paradigm in children of mothers with atopic illnesses: A birth cohort study from the United Kingdom.

Atopic dermatitis (AD) is thought to precede the onset of other allergic illness (OAI) in a temporal progression (ie, atopic march), yet the timing and progression has been questioned. It is also unclear how parental allergic illness impacts the development of these illnesses in offspring. (1) Explore risk of incident AD and (2) timing of allergic disease onset in children of mothers with AD compared with mothers without AD from the United Kingdom. We created a birth cohort of mother-child pairs using IQVIA Medical Research Data database and developed Cox proportional models to examine the above associations (hazard ratio, HR [95% confidence interval, CI]). Among 1,224,243 child-mother pairs, mean child (standard deviation) follow-up time was 10.8 (8.3) years and 50.1% were males (N = 600,905). Children were 59% (HR = 1.59 [1.57, 1.60]) more likely to have AD if their mothers had AD compared with no AD with mean age of first AD diagnosis at 3.3 (4.8) years. Most children with any diagnosis of AD present with AD first (91.0%); however, in those with asthma, only 67.8% developed AD first. Children born to mothers with AD are more prone to develop AD and some develop OAI first, suggesting that not all follow the same sequential pathway. • The atopic march describes the temporal association of initial onset of atopic dermatitis at an early age followed by subsequent development of other atopic illness. • We observed that whereas this may be true for some, not all patients with allergic diseases including atopic dermatitis, will follow the same "sequential" march. [ABSTRACT FROM AUTHOR]