Inclusion Criteria:  All eligible adult people (aged ≥ 18) registered with GP practices contributing data to OPCRD between January 1, 2010 and January 1, 2020, were eligible for inclusion in the study.  Exclusion Criteria:  People with less than 5 years potential follow up. People with atopic dermatitis that was not active atopic dermatitis during the study period. People without atopic dermatitis but diagnosed with other skin conditions.