Yoshio Komachi

Trends for coronary heart disease and stroke and their risk factors in Japan.

Disease surveillance and population surveys of risk characteristics in a northeast rural community of Japan (1965 census population, 7,030) are combined in an attempt to relate morbidity and risk factor trends for coronary heart disease and stroke during the last 2 decades. Between 1964 and 1983, the incidence of coronary heart disease (i.e., combined myocardial infarction, angina pectoris, and sudden death) did not change significantly among men and women ages 40-69, and was lower than that for stroke. The incidence of all stroke declined about 60% for both men and women, ages 40-69, with a significant decrease in cerebral hemorrhage for both sexes and in cerebral infarction for men. Between 1963-1966 and 1980-1983, significant upward shifts occurred in the means and distributions of serum total cholesterol and serum total protein in every age and sex group, primarily during the 1st decade. Age-adjusted mean cholesterol levels rose 22 mg/dl to the 1980-1983 mean of 179 mg/dl in men ages 40-69. In women ages 40-69, the mean rose 29 mg/dl to 192 mg/dl. Among nutrients, animal fat intake doubled in men ages 40-59 from 4.5% of daily calories in 1969 to 9.6% in 1980-1983. Animal protein intake also increased, from 5.8% to 7.1%. Most of this increase occurred between 1969 and 1972-1975 and may be attributable to an increased intake of meat, eggs and dairy products. From 1963-1966 to 1980-1983, mean relative weight index rose significantly for all age-sex groups except men ages 50-69. Mean systolic and diastolic blood pressure levels declined for every age-sex group, with a 15-mm Hg age-adjusted decrease in systolic, 4-mm Hg decrease in diastolic pressure among men ages 40-69, and a 11-mm Hg systolic and 4-mm Hg diastolic decrease for women. Two cohorts of men and women ages 40-69 at baseline were followed for disease incidence: an early cohort (2,257 persons) followed from 1963-1966 to 1973 and a later cohort (2,711 persons) followed from 1972-1975 to 1983. In these cohorts, significant risk prediction for cerebral hemorrhage and infarction was obtained with blood pressure level and end organ effects in the electrocardiogram and fundus photographs. Serum cholesterol was inversely associated with cerebral hemorrhage in the early cohort but not in the later.(ABSTRACT TRUNCATED AT 400 WORDS)

Alcohol Intake and the Risk of Cardiovascular Disease in Middle-Aged Japanese Men

BACKGROUND AND PURPOSE Understanding the effects of alcohol intake on stroke and other cardiovascular diseases is an important issue for public health. METHODS A 10.5-year prospective study of the relationship between alcohol intake and cardiovascular disease incidence was conducted in 2890 men, aged 40 to 69 years and free of a history of stroke and coronary heart disease, in three rural communities of Japan. RESULTS One hundred seventy-eight strokes (40 intracerebral hemorrhages, 18 subarachnoid hemorrhages, 104 nonhemorrhagic strokes, and 16 unclassified strokes), 34 coronary heart disease events, and 19 sudden unclassified deaths occurred. Drinkers of > or = 70 g/d ethanol had an approximately 2.5 times higher age-adjusted risk of all stroke than never-drinkers; the excess risk was more evident for hemorrhagic stroke than nonhemorrhagic stroke. When hypertension category, serum total cholesterol level, cigarette smoking, and diabetes mellitus were taken into account, these excess risks were reduced but remained significant for all stroke (2.0; 95% confidence interval, 1.3 to 3.1) and hemorrhagic stroke (3.4; 95% confidence interval, 1.2 to 9.2). A J-shaped relationship was suggested between alcohol intake and risk of nonhemorrhagic stroke; drinkers of < 42 g/d ethanol had a slightly lower risk and heavy drinkers had a higher risk than never-drinkers. Current drinkers had a slightly lower risk of coronary heart disease than never-drinkers, although the risk difference was not statistically significant. The age-adjusted risk of sudden death was 10 times higher in heavy drinkers than never-drinkers, and the excess risk did not change when the covariates were controlled for. Total cardiovascular disease showed a similar pattern as did all stroke. CONCLUSIONS Heavy drinking appeared to increase the risk of hemorrhagic stroke, in part due to hypertension, and to increase the risk of sudden death, which was probably due to drinking per se. Light or moderate alcohol consumption seemed to protect against nonhemorrhagic stroke and coronary heart disease.

Associations of serum total cholesterol, different types of stroke, and stenosis distribution of cerebral arteries. The Akita Pathology Study.

Background and Purpose The relation between serum total cholesterol levels and stroke is controversial. The Akita Pathology Study provides data on the association of serum total cholesterol, different types of stroke, and distribution of stenosis in cerebral arteries. Methods The data are based on 750 autopsied men aged 30 years and older who were admitted to a local hospital in northeast Japan between 1966 and 1984. The overall autopsy rate was 88%. The grade of stenosis in the cerebral arteries was determined blindly by one pathologist using Bakers method for basal cerebral arteries (atherosclerosis scores) and using microscopic examination of a single basal ganglion slide for the intracerebral penetrating arteries (arteriolosclerosis scores). Results The age-adjusted mean value of serum total cholesterol concentration was 164 mg/dL for cerebral hemorrhage, 177 mg/dL for infarction in penetrating artery regions, and 200 mg/dL for infarction in cortical artery regions. Mean serum cholesterol was lower in deaths caused by cerebral hemorrhage than in those caused by myocardial infarction and other cardiovascular disease. Mean atherosclerosis score of basal cerebral arteries was low for cerebral hemorrhage, intermediate for penetrating artery infarction, and high for cortical artery infarction. Stenosis of both basal and penetrating arteries was minimum or absent in cases of cerebral hemorrhage. Only the basal arteries were stenotic in cases of cortical artery infarction, whereas both basal and penetrating arteries were stenosed in cases of penetrating artery infarction. There were positive associations of serum cholesterol with stenosis of basal and penetrating arteries. Among cases of cerebral hemorrhage, serum total cholesterol levels were even lower in men with no significant stenosis in either basal or penetrating arteries than in men with stenosis in either type of artery. Conclusions The association of serum cholesterol with pathogenesis varies among stroke types. Elevated serum cholesterol levels were associated with the presence of cortical artery infarction, while low serum cholesterol levels were associated with cerebral hemorrhage.

Multivariate analysis of risk factors for stroke eight-year follow-up study of farming villages in Akita, Japan

Akita Prefecture has an especially high mortality rate from stroke, and its age-adjusted death rate from stroke is the highest in Japan. We have carried out an epidemiological survey of cardio- and cerebrovascular diseases (CVD) in farming villages in this prefecture since 1963, with a response rate of 84%. During our 8-year follow-up, 94 new stroke cases were observed among 1,814 subjects. Multiple logistic function analysis was carried out on nonstroke and stroke cases from subjects aged 40 to 69 years at time of initial examination, in order to clarify the risk factors for stroke. The analysis used eight variables: age, sex, systolic blood pressure, obesity index, urinary sugar, urinary protein, serum total cholesterol, and total protein. The results showed that hypertension was the most important risk factor for stroke. However, regarding cholesterol, multivariate analysis showed that among men and women aged 40 to 69 years at entry, subjects with low serum total cholesterol levels were more prone to cerebral hemorrhage, but that serum cholesterol level had no weight as a risk factor for cerebral infarction. These results correspond well with the observed fact that stroke incidence or death rate in Japan is higher in populations with high prevalence of hypertension and low concentration of cholesterol, and also with the fact that death rate from hemorrhage declines with the increment of serum total cholesterol and the westernization of diet.

Trends in the Incidence of Coronary Heart Disease and Stroke and Their Risk Factors in Japan, 1964 to 2003 : The Akita-Osaka Study

A continuous decline in mortality and morbidity from coronary heart disease (CHD) has been documented in the U.S. ([1–4][1]). This decline is accompanied by a reduction in serum total cholesterol levels, which has been attributed to improvements in medical care and community-based prevention

Trends in the incidence of coronary heart disease and stroke and the prevalence of cardiovascular risk factors among Japanese men from 1963 to 1994

PURPOSE To determine trends in the incidence of cardiovascular disease in Japan, we examined observational data on coronary heart disease, stroke, and cardiovascular risk factors among urban Japanese working men. SUBJECTS AND METHODS The surveyed population included all male employees aged 40 to 59 years who worked for eight industrial companies in Osaka, the second largest metropolitan city in Japan. Surveillance for cardiovascular disease and risk factors was conducted from 1963 to 1994. RESULTS The age-adjusted incidence of coronary heart disease increased from 0.4 per 1000 person-years during 1963 to 1970, to 1.5 per 1000 person-years during 1979 to 1986, and then plateaued until 1987 to 1994 (P for trend = 0.002), whereas the incidence of stroke declined from 1.2 per 1,000 person-years during 1971 to 1978, to 0.6 per 1,000 person-years in 1987 to 1994 (P for trend = 0.02). The age-adjusted mean (+/- SD) total cholesterol level, which was 4.87 +/- 2.88 mmol/L during 1963 to 1966, increased to 5.11 +/- 0.62 mmol/L during 1982 to 1983 (P <0.001), and 5.09 +/- 0.75 mmol/L during 1990 to 1991. Both mean systolic and diastolic blood pressures increased by 1 mm Hg between the periods of 1966 to 1967 and 1982 to 1983, and declined below the 1966 to 1967 levels during 1990 to 1991. The prevalence of smoking declined from 72% during 1975 to 1976, to 58% during 1990 to 1991 (P for trend <0.001). CONCLUSION Although these findings were limited to urban middle-aged men, the increase in serum cholesterol is likely to attenuate the reduction in future rates of coronary heart disease in Japan that would have been expected to result from the declining prevalence of smoking.

Alcohol intake and hypertension among urban and rural Japanese populations

A significant positive relationship was found between alcohol intake and blood pressure for men 40-69 years old living in urban Osaka (492 men) and in rural Akita (395 men), Japan, surveyed from 1975 to 1977. Both mean blood pressure and the prevalence of hypertension were related to alcohol intake in a graded fashion. Stepwise multiple regression also showed that both systolic and diastolic pressure were associated with alcohol intake independent of ponderosity index, serum cholesterol, triglycerides, hemoglobin, uric acid, smoking, and age. This cross-sectional study indicates a continuous--and not a threshold--relationship between alcohol and blood pressure, with the effect of even moderate consumption, e.g. 28-55 g per day (equivalent to about 2-4 U.S. drinks per day).

Community-based education classes for hypertension control : A 1.5-year randomized controlled trial

Community-based hypertension control is important for primary prevention of cardiovascular disease. In this study, untreated men and women aged 35 to 69 years were randomly assigned to an intervention (n=56) or control (n=55) group in a 1.5-year community-based education program. Subjects had no evidence of hypertensive end-organ defects and had screening blood pressures of 140 to 179 mm Hg systolic and/or 90 to 109 mm Hg diastolic, with no difference in mean blood pressure between groups (148 to 150 mm Hg for mean systolic and 83 to 84 mm Hg for mean diastolic pressures). The intervention group took four education classes in the first 6 months and four classes during the next year, and the control group took two classes. Health education focused on reduced dietary sodium and increased milk intake, brisk walking, and, if necessary, reduction of alcohol and sugar intakes. Antihypertensive medication was started less often in the intervention than in the control group at 1.5 years (9% versus 24%, P <.05). Mean systolic pressure was 5 to 6 mm Hg less in the intervention than in the control group at both 6 months and 1.5 years (P <.05), with or without inclusion of those subjects who began antihypertensive medication. Diastolic pressure and body mass index did not change significantly between groups. Urinary sodium excretion declined in the intervention but not in the control group (differences between groups: P=.04 at 6 months and P=.07 at 1.5 years). According to a behavioral questionnaire, sodium reduction and milk increase were greater in the intervention than the control group (sodium: P <.01 at 6 months and P=.08 at 1.5 years; milk: P <.001 at 6 months and P <.01 at 1.5 years). Mean ethanol intake was reduced in the intervention but not the control group (P=.04 at 1.5 years). This community-based hypertension control program was effective in reducing systolic pressure levels by nonpharmacological means during the first 6 months and maintaining the reduction for 1.5 years.

Dietary intake and serum total cholesterol level: their relationship to different lifestyles in several Japanese populations.

Serum total cholesterol level and dietary intake were surveyed 1975–1977 in six Japanese population groups with different lifestyles, including groups in both rural (Akita and Kochi) and urban (Osaka) areas. Clerical workers in Osaka, who had the most westernized lifestyle of all the study groups, had the highest mean serum total cholesterol level (202 mg/dl for men ages 40-49 and 50-59 years), while farmers in Akita had the lowest mean serum total cholesterol level (163 mg/dl for men 40-49 years old, 159 mg/dl for men 50-59 years old, 165 mg/dl for men 60-69 years old). Nutrient intake data for men ages 40-59 years showed 23% of calories from fat for clerical workers in Osaka, the highest among the study groups, whereas farmers in Akita showed a low level of 14%. The ratio of dietary polyunsaturated to saturated fatty acids was over 1.1 for all groups. Cholesterol intake was 339-487 mg/day. Total carbohydrate as a percentage of calories was 53-65%; 75-80% of carbohydrate energy was ingested from cereals. Sugar accounted for less than 3.5% of total calories.In the cross-group correlation analysis between dietary lipid intake and serum total cholesterol, a significant strong positive correlation was found between the dietary lipid factor (44 of Keys et al. and the mean serum total cholesterol level. A weak but significant correlation was observed between the dietary lipid factor and serum total cholesterol for individual inhabitants of Osaka.

Effects of a Long-term Hypertension Control Program on Stroke Incidence and Prevalence in a Rural Community in Northeastern Japan

BACKGROUND AND PURPOSE Although randomized clinical trials have demonstrated the benefit of antihypertensive treatment in preventing stroke, the effectiveness of community-based programs is largely unknown. We investigated long-term community-based prevention activities. METHODS In rural northeastern Japan, people aged > or = 30 years numbered 3219 in the full intervention community and 1468 in the minimal intervention community in 1965. Systematic blood pressure screening and health education began in 1963. Stroke was registered through 1987. RESULTS More than 80% of people aged 40 to 69 years were screened in both communities in the 1960s. One community charged for screening services after 1968, whereas the other community intensified intervention; subsequently, screening rates and the follow-up of hypertensive individuals declined in the minimal intervention community, especially in men. In men, stroke incidence declined more (P < 0.001) in the full intervention (42% in the period 1970 to 1975, 53% in the period 1976 to 1981, and 75% in the period 1982 to 1987) than in the minimal intervention community (5% increase, 20% decrease, and 29% decrease, respectively); in women, the stroke incidence declined about 45% to 65% in both communities. Changes in stroke prevalence paralleled those in stroke incidence. Trends in systolic blood pressure levels tend to explain the differential stroke rates in men. CONCLUSIONS Delivery of hypertension control services through intensive, free, community-wide screening and health education was effective in prevention of stroke for men in a community.