Anterior choroidal artery territory infarcts.

Wiebers DO. Duration of cigarette smoking is the strongest pre-dictor of severe extracranial carotid artery atherosclerosis. Response We would like to thank Dr Alpert for his comment on our article, in which we demonstrated that extracranial carotid atherosclerosis is increasing in Japanese patients with brain ischemia. 1 We also reviewed some vascular risk factors possibly related to our findings; these include hypertension, diabetes mellitus, ischemic heart disease, and hypercholesterolemia. This list of risk factors is rather incomplete because of the failure to obtain thorough medical histories from the early patients (1963 to 1965). We are aware that some important risk factors, including smoking, are missing from our analysis, and hence we do not conclude that diabetes mellitus is the only risk factor responsible for the change in the rate of extracranial cerebral atherosclerosis in the Japanese population. Accordingly, we respect the comment made by Dr Alpert, and do not exclude the possibility that smoking played an important role in the increase in extracranial carotid atherosclerosis revealed by our analysis. Nonetheless, there is some evidence against the involvement of smoking in the increase in extracranial carotid lesions in Japan. First of all, the proportion of smokers in the Japanese population overall has been decreasing during the past 30 years. 2-3 Although we do not know the exact proportion of cigarette smokers among our patients, there is no reason to believe that smokers were preferentially incorporated into the recent group of subjects or were excluded from the early group. Second, in Japan approximately five times as many men as women smoke, 2 and the early group consisted largely of male patients. These factors, taken together, lead us to suppose that the proportion of smokers was higher in the early group than in the recent group. Finally, the frequency of extracranial carotid lesions was similar in men and women in our analysis, despite the difference in smoking rates between the sexes. These lines of evidence apparently contradict the notion that smoking is responsible for the increase in extra-cranial carotid lesions in our study. According to the results of our population-based epidemiological study in a Japanese rural community, Hisayama, rates of hypertension and smoking have decreased in recent years whereas those of hypercholesterolemia, obesity, and glucose intolerance have significantly increased. 2 Such metabolic disorders appear to play more important roles than ever in the development of ischemic stroke in Japan. There may be subtle …