The clinical features and course of aortitis syndrome were studied in 11 women older than 40 years of age. The patients were Japanese women, mean age 57 +/- 6 years old, who were followed for 6.9 +/- 3.8 years. Data from 24 young patients were used for comparison. In the older patients, systemic hypertension (73%), calcification of the aorta (73%), left ventricular hypertrophy (92%) and cardiomegaly (82%) were frequent, whereas the erythrocyte sedimentation rate was normal in 5 patients and only slightly accelerated in 6. C-reactive protein was positive in 2. The incidence of cardiac involvement and inflammatory signs was significantly different from findings in the young patients. Aortic regurgitation (AR) (55%) was significantly more frequent and renal artery stenosis was not observed. Other arterial lesions revealed a pattern similar to those seen in the young patients. An irregular luminal surface, kinking and calcification were present in the lesions in the older patients. The survival rate at 5 years was 80%. Five of 6 patients with AR had congestive heart failure, 4 of whom died. One died after a stroke. Thus, aortitis syndrome in older patients has a long course. There is usually an associated AR, renal artery stenosis is rare and other arterial lesions do not change a great deal. The prognosis may be good, but depends on the association of AR.