Background: Data on the natural history and prognostic variables of chronic urticaria and its subtypes are scarce.
Method: In order to inform our patients better about their prognosis we conducted an historical cohort study of patients who visited a tertiary referral centre at a university hospital between 1968 and 1990. Of 950 patients who were seen in our clinic we could trace 544 patients by using telephone directories, general practitioner records and population registers. These patients were sent a questionnaire.
Results: The response to the questionnaire was 68.4% (372 patients). Patients with severe disease and longer lasting disease at the time of the first visit proved to have a worse prognosis than patients with milder disease. The proportion cleared after 5 and 10 years was 29% and 44%, respectively. Dermographism showed the best prognosis and cold urticaria the worst. Patients with idiopathic urticaria without angioedema and the patients with angioedema did not differ significantly in prognosis.
Conclusions: Although in this retrospective study patients with severe disease may have been more inclined to respond, we may conclude that the study results indicate a very refractory course of chronic urticaria in patients visiting a specialized dermatological unit. The study is not comparable with studies in patients visiting a general practitioner or a dermatology unit in a general hospital, but highlights the chronicity of the disease in this subgroup of patients with severe urticaria.