Respiratory atopy (RA) is frequently associated with atopic dermatitis (AD) and the age of onset is usually later than that of the dermatitis.

The aim of this study was to investigate the prevalence, the onset, and the duration of RA associated with AD in Korea. We also tried to correlate the existence of RA with the severity and prognosis of AD.

One hundred and eighty one patients with AD were studied. Information about the age at onset and the duration of RA were obtained from the medical history of patients or from the medical records. The severity of AD was graded.

RA was found in 66 cases of AD (36.5%). The average age at onset of asthma was 6 years and the average duration of asthma was 6 years. The average age at onset of allergic rhinitis (AR) was 12.4 years and the average duration of AR was 6.8 years. The prevalence of asthma with AD was the most common in the age group between 8 and 11 years while the prevalence of AR was the most common in the age group between 20 and 23 years. The higher occurrence of RA in the older age group was considered to represent persistence of AD in-to adult life. We could not find any difference in the severity of AD between pure AD patients and AD patients with RA.

The prevalence of RA in AD in Korea was considered to be similar to that of other reports. The average onset of asthma in Korea was a little later, whereas the average on-set of AR was a little earlier than that in the other reports. The duration of RA, which has hardly been mentioned in the literature, was considered to be about 6 years in Korea. It is likely that RA is a poor prognostic factor for AD, but does not affect severity of dermatitis.