Background  In contrast to asthma and rhinitis, few studies among adults investigating the prevalence and risk factors of eczema have been published.

Objectives  To investigate the prevalence and risk factors of eczema among adults in West Sweden. A further aim was to study the associations between asthma, rhinitis and eczema.

Methods  A questionnaire on respiratory health was mailed in 2008 to 30 000 randomly selected subjects in West Sweden aged 16–75 years; 62% responded. The questionnaire included questions about eczema, respiratory symptoms and diseases and their possible determinants. A subgroup of 669 subjects underwent skin prick testing against common airborne allergens.

Results  ‘Eczema ever’ was reported by 40·7% and ‘current eczema’ by 11·5%. Both conditions were significantly more common among women. The prevalence decreased with increasing age. The coexistence of both asthma and rhinitis with eczema was common. The main risk factors were family history of allergy and asthma. The dominant environmental risk factor was occupational exposure to gas, dust or fumes. Smoking increased the risk. Eczema was associated with urbanization, while growing up on a farm was associated with a decreased risk. Added one by one to the multivariate model, asthma, allergic rhinitis and any positive skin prick test were associated with eczema.

Conclusions  Eczema among adults is a common disease with more women than men having and having had eczema. Eczema is associated with other atopic diseases and with airway symptoms. Hereditary factors and exposure to gas, dust and fumes are associated with eczema.