All participants in the medical examination system of Tokyo Women's Medical College, who received a medical check-up in 1987, were followed for 5 years, and the incidence of arteriosclerotic diseases and their risk factors were studied. Logistic regression analysis was used to determine the risk factors for arteriosclerotic diseases. The incidence of disases were studied at each level of risk factors proven to be related to these diseases by logistic regression analysis. Significance was analyzed by X² test.
1) The incidence was calculated as 1.07 persons for myocardial infarction, 2.50 persons for effort angina, 1.36 persons for stroke, 0.79 persons for transient ischemic attacks and 0.14 persons for arteriosclerosis obliterans per 1, 000 persons per year.
2) The only risk factor for myocardial infarction was age, while those for effort angina were age, LDL, HDL and maximal blood pressure. The risk factors for stroke were age and blood pressure, those of transient ischemic attacks were age and LDL, and those of aortic aneurysm were age, LDL and maximal blood pressure. The incidence of these arteriosclerotic diseases increased at higher levels of LDL and blood pressure, and at lower levels of HDL.
3) Our new index, LDL/HDL×5, was a more sensitive predictor of arteriosclerotic diseases than LDL or HDL.

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To clarify the incidence of extracranial carotid lesions in patients with aortic aneurysm and arteriosclerosis obliterans, carotid ultrasonography was performed in 41 patients with aortic aneurysm (AA group) and 62 patients with arteriosclerosis obliterans (ASO group). In this study, aortic aneurysm (AA) was diagnosed when an enlarged aorta measured more than 40mm in diameter (or infra-renal aorta more than 30mm in diameter) or when a pseudo-lumen was demonstrated within the aortic wall by computed tomography (CT) and angiography. Abdominal AA was detected in 30 patients, thoracic AA in 7, and dissecting AA in 4. ASO in patients with intermittent claudication showed obstruction of peripheral arteries on angiography. The control group consisted of 40 age-matched controls (mean age: 73.4 years) who met 4 criteria: 1) ankle pressure index more than 1.0; 2) absence of pulsating abnormal mass in the abdomen; 3) absence of dilated aorta on chest X-ray film; and 4) absence of cerebrovascular lesion on brain CT. Plaque, one of the carotid lesions seen on B-mode ultrasonography, was defined as a localized thickened intima-media complex measuring more than 2.1mm. Furthermore, plaque was divided into two types according to the ratio of plaque length to thickness; mural plaque (≥3) and nodular plaque (<3). In the AA and ASO groups, the ratio of males to females, the incidence of hypertension and smoking were significantly higher than in the control group. Compared to controls, patients with more than three of four risk factors (hypertension, diabetes, hypercholesterolemia, and smoking) were significantly more frequent. Carotid lesions were seen in 68.3% of the AA group, and in 85.5% of the ASO group. The incidence of carotid lesions was significantly higher than that in the control group, although there was also a significant difference between the AA and ASO groups. The ratio of plaque to carotid arteries was also elevated in both the AA and ASO groups. Especially, mural plaque was frequently noted in the ASO group, while the mean size of mural plaque was larger in the AA group. These findings suggest that patients with either aortic aneurysms or arteriosclerosis obliterans were more likely to have advanced carotid lesions, but the probability was significantly higher in the former. These patients, therefore, should be managed with caution to check for carotid lesions and cerebrovascular disease. If possible, the occurrance or progression of cerebrovascular disease should be prevented.

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An antiallergic drug, pemirolast potassium (TBX), has been shown to inhibit the release of pro-inflammatory mediators from mast cells and eosinophils through the inhibition of intracellular calcium mobilization and modulation of phosphatidylinositol (PI) turnover.
We have studied the effect of TBX on cell proliferation and migration of vascular smooth muscle cells (SMCs) in vitro. SMCs were cultured from rat aorta and were stimulated with fetal calf serum (FCS), platelet-derived growth factor (PDGF), angiotensin II (ATII) or endothelfin I (ET-I).
In the cell proliferation assay. DNA synthesis was measured as BrdU incorporation into DNA at 36hr after FCS stimulation. TBX at concentrations from 10^-7 to 10^-4M inhibited BrdU incorporation into DNA. This finding was consistent with the observation that TBX dose-dependently decreased the number of cells at 24, 36 and 48hr after FCS stimulation. Furthermore, TBX (10^-4M) inhibited cell proliferation stimulated with PDGF, ATII or ET-I.
On the migration, the effect of TBX at concentrations from 10^-7 to 10^-4M was examined by Boyden's chamber method. TBX dose-dependently inhibited cell migration as determined by number of cells.
Morever, we examined the inhibitory effect of TBX on 1, 4, 5-IP₃ formation induced by ATII in SMCs. TBX also suppressed PI turnover.
These findings indicated that TBX may intervene initiation and progression of atherosclerosis through the inhibition of proliferation and migration of arterial SMCs. Therefore, TBX may be clinically applicable for the prevention of restenosis after percutaneous transluminal coronary angioplasty.

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Studies show that arteriosclerosis advances first in the aorta and then proceeds to the cerebral and coronary arteries. Because the aortic pulse wave velocity (PWV) can be used to estimate the extent of arteriosclerosis in the aorta, the use of PWV may allow earlier detection of arteriosclerotic diseases.
This study examined the relationship between PWV and other arteriosclerotic indicators including (1) arteriolar sclerotic changes in the retina as evaluated by Scheie's method (≥grade II); (2) ischemic ECG changes (Minnesota code: 4-1, 4-2, 4-3, 4-4 and/or 5-1, 5-2, 5-3); and (3) hypertension determined as systolic pressure ≥160mmHg and/or diastolic pressure >95mmHg. Subjects were 221, 564 male urban workers, 20-69 years of age, who participated in cardiovascular disease screening in major cities in Japan. This study sample did not include patients with hypertension, diabetes, hyperlipidemia, or gout, or those having a history of cardio- and/or cerebrovascular diseases.
We examined the prevalence of each of the above three indicators at various PWV levels (<7.0, 7.0-7.9, 8.0-8.9, 9.0-9.9, ≥10.0m/sec.) in different age groups (20-29, 30-39, 40-49, 50-59, 60-69 years old).
The prevalence of each of the three indicators increased exponentially as the PWV became faster in all age groups examined with the exception of the prevalence of hypertension due to elevated diastolic pressure in patients 60-69 years old; the prevalence of each condition increased significantly at PWV scores of 8.0m/sec or greater among those under 60 years old and 9.0m/sec or greater among those 60-69 years old.
It is suggested that PWV advances prior to the appearance of the indicators examined and that the use of PWV in mass screenings can contribute significantly to the prevention of arteriosclerotic diseases.

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Data from cardiovascular disease screening of 286, 292 male urban workers over a period of ten years (1983-93) were analyzed dividing the ten years into three periods: I. 1983-87; II. 1988-90; and III, 1991-93.
We examined the prevalence of the combination of three disease indicators (called HHD): hypertension (HT), hypertriglyceridemia (HTG), and diabetes mellitus (DM), for each period to observe the trend.
HT was defined as a systolic pressure ≥150mmHg and/or diastolic pressure ≥90mmHg or persons with a history of hypertension; HTG referred as those with triglyceride levels ≥150mg/dl; DM was determined as fasting glucosuria or a history of diabetes. Controls were subjects without HHD or any detectable arteriosclerotic diseases. We also examined age-specific averages of aortic pulse wave velocity (PWV) and age-specific prevalence of arteriolar sclerotic changes ≥grade II by Scheie's method and ischemic ECG changes (Minnesota code: 4-1∼4 and/or 5-1∼3) for each group (HHD, HT, HTG, and DM) for each of the three periods.
The prevalence of HHD correlated with aging with an increasing trend in persons 40-49 years old but a decreasing trend was noted in persons 50-59 and 60-69 years old. It was observed that compared to controls, the average PWV values of the HHD group were higher in each age-group for each period, and the prevalence of abnormal arteriolar sclerotic changes and ischemic ECG changes was 20.8-34.9 times and 5.6-10.7 times higher, respectively, for the HHD group in each age-group for each period.
Thus, it was concluded that persons with HHD develop arteriosclerotic conditions much faster than healthy individuals and are considered to be at higher risk for arteriosclerotic diseases.

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