AIM: Although Takayasu arteritis (TAK) and giant cell arteritis (GCA) have been considered as distinct disease entities, similarities of these diseases have been recently reported. However, little data is available regarding this issue in Japanese patients with TAK and GCA. In addition, the classification criteria for TAK established in 1990 by the American College of Rheumatology (ACR) have been criticized due to the age restriction for disease onset (≤ 40 years). Thus, we aimed to compare the clinical characteristics of Japanese patients with TAK and those with GCA and to clarify whether clinical differences existed between patients with early-onset (≤ 40 years) and late-onset (> 40 years) TAK. METHODS: We enrolled 86 patients with TAK and nine with GCA who visited our department from 1990 to 2014. The diagnoses of TAK and GCA were based on the criteria of the Japanese Circulation Society and the ACR, respectively. RESULTS: Mean ages at onset for TAK and GCA were 36.4 and 71.0 years, respectively. Patients with TAK had significantly higher incidences of aortic regurgitation and carotid and subclavian arterial involvement, lower frequencies of polymyalgia rheumatica, and better prognoses than those with GCA. In contrast, the clinical characteristics, distribution of arterial lesions, treatments administered, and prognoses of patients with early- and late-onset TAK were comparable. CONCLUSIONS: These results suggested that TAK and GCA differed substantially, and that the age restriction (≤ 40 years) may not be necessary for the diagnosis of TAK.
AIM: Although Takayasu arteritis (TAK) and giant cell arteritis (GCA) have been considered as distinct disease entities, similarities of these diseases have been recently reported. However, little data is available regarding this issue in Japanese patients with TAK and GCA. In addition, the classification criteria for TAK established in 1990 by the American College of Rheumatology (ACR) have been criticized due to the age restriction for disease onset (≤ 40 years). Thus, we aimed to compare the clinical characteristics of Japanese patients with TAK and those with GCA and to clarify whether clinical differences existed between patients with early-onset (≤ 40 years) and late-onset (> 40 years) TAK. METHODS: We enrolled 86 patients with TAK and nine with GCA who visited our department from 1990 to 2014. The diagnoses of TAK and GCA were based on the criteria of the Japanese Circulation Society and the ACR, respectively. RESULTS: Mean ages at onset for TAK and GCA were 36.4 and 71.0 years, respectively. Patients with TAK had significantly higher incidences of aortic regurgitation and carotid and subclavian arterial involvement, lower frequencies of polymyalgia rheumatica, and better prognoses than those with GCA. In contrast, the clinical characteristics, distribution of arterial lesions, treatments administered, and prognoses of patients with early- and late-onset TAK were comparable. CONCLUSIONS: These results suggested that TAK and GCA differed substantially, and that the age restriction (≤ 40 years) may not be necessary for the diagnosis of TAK.