The epidemiology of eczema in children and adults in England: A population-based study using primary care data.

BACKGROUND Whilst eczema is a common inflammatory skin condition, we lack contemporary estimates of disease incidence and prevalence across the lifespan. OBJECTIVE To estimate the incidence and prevalence of eczema in children and adults in England and variation by sociodemographic factors (sex, socioeconomic status, ethnicity, and geography). METHODS We used the Royal College of General Practitioners Research and Surveillance Centre primary care research database of 3.85 million children and adults registered with participating practices between 2009 and 2018 inclusive. Eczema incidence was defined as the first-ever diagnosis of eczema recorded in the primary care record, eczema prevalence was defined as fulfilment of criteria for active eczema (two eczema records appearing in the primary care record within any one-year period). RESULTS Eczema incidence was highest in infants younger than 1 year (15.0 per 100 person-years), lowest in adults aged 40-49 (0.35 p/100 person-years), and increased from middle age to a second smaller peak in people 80 years or older (0.79 p/100 person-years). Eczema prevalence was highest in children aged 2 (16.5%) and lowest in adults aged 30-39 (2.8%). Eczema incidence was higher in male infants (<2) and male adults older than 70; for all other ages, incidence in females was higher. Eczema was more common in Asian and black ethnic groups than people of white ethnicity. Higher socioeconomic status was associated with a greater incidence of eczema in infants younger than 2, but the reverse was seen for all other age groups. Incidence and prevalence of eczema were greater in urban settings and in North-West England. CONCLUSIONS AND CLINICAL RELEVANCE Eczema has a bimodal distribution across the life span. We observed differences in incidence and prevalence of eczema by ethnicity, geography, sex, and socioeconomic status, which varied in magnitude throughout life.