Akio Yamamoto

University of Tsukuba, Tsukuba, Ibaraki-ken, Japan

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Publications (27)125.63 Total impact

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    ABSTRACT: Prospective epidemiologic studies have generated mixed results regarding the association between saturated fatty acid (SFA) intake and risk of ischemic heart disease (IHD) and stroke. These associations have not been extensively studied in Asians. The aim of this study was to test the hypothesis that SFA intake is associated with the risk of cardiovascular disease mortality in Japanese whose average SFA intake is low. The Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study) comprised 58,453 Japanese men and women who completed a food-frequency questionnaire. Participants were aged 40-79 y at baseline (1988-1990) and were followed up for 14.1 y. Associations of energy-adjusted SFA intake with mortality from stroke (intraparenchymal and subarachnoid hemorrhages and ischemic stroke) and heart diseases (IHD, cardiac arrest, and heart failure) were examined after adjustment for age, sex, and cardiovascular disease risk and dietary factors. We observed inverse associations of SFA intake with mortality from total stroke [n = 976; multivariable hazard ratio (95% CI) for highest compared with lowest quintiles: 0.69 (0.53, 0.89); P for trend = 0.004], intraparenchymal hemorrhage [n = 224; 0.48 (0.27, 0.85); P for trend = 0.03], and ischemic stroke [n = 321; 0.58 (0.37, 0.90); P for trend = 0.01]. No multivariable-adjusted associations were observed between SFA and mortality from subarachnoid hemorrhage [n = 153; 0.91 (0.46, 1.80); P for trend = 0.47] and heart disease [n = 836; 0.89 (0.68, 1.15); P for trend = 0.59]. SFA intake was inversely associated with mortality from total stroke, including intraparenchymal hemorrhage and ischemic stroke subtypes, in this Japanese cohort.
    American Journal of Clinical Nutrition 10/2010; 92(4):759-65. · 6.50 Impact Factor
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    ABSTRACT: The effects of coffee and green, black and oolong teas and caffeine intake on cardiovascular disease (CVD) mortality have not been well defined in Asian countries. To examine the relationship between the consumption of these beverages and risk of mortality from CVD, 76,979 individuals aged 40-79 years free of stroke, coronary heart disease (CHD) and cancer at entry were prospectively followed. The daily consumption of beverages was assessed by questionnaires. 1362 deaths were documented from strokes and 650 deaths from CHD after 1,010,787 person-years of follow-up. Compared with non-drinkers of coffee, the multivariable HR and 95% CI for those drinking 1-6 cups/week, 1-2 cups/day and ≥ 3 cups/day were 0.78 (0.50 to 1.20), 0.67 (0.47 to 0.96) and 0.45 (0.17 to 0.87) for strokes among men (p = 0.009 for trend). Compared with non-drinkers of green tea, the multivariable HR for those drinking 1-6 cups/week, 1-2 cups/day, 3-5 cups/day and ≥ 6 cups/day were 0.34 (0.06-1.75), 0.28 (0.07-1.11), 0.39 (0.18-0.85) and 0.42 (0.17-0.88) for CHD among women (p = 0.038 for trend). As for oolong tea, the multivariable HR of those drinking 1-6 cups/week and ≥ 1 cups/day were 1.00 (0.65-1.55) and 0.39 (0.17-0.88) for total CVD among men (p = 0.049 for trend). Risk reduction for total CVD across categories of caffeine intake was most prominently observed in the second highest quintile, with a 38% lower risk among men and 22% among women. Consumption of coffee, green tea and oolong tea and total caffeine intake was associated with a reduced risk of mortality from CVD.
    Journal of epidemiology and community health 12/2009; 65(3):230-40. · 3.04 Impact Factor
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    ABSTRACT: To examine the association of plant-based food intakes with CVD and total mortality among Japanese. In the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, 25 206 men and 34 279 women aged 40-79 years, whose fruit, vegetable and bean intakes were assessed by questionnaire at baseline in 1988-90, were followed for 13 years. Deaths from total stroke, stroke subtypes, CHD and total CVD, according to the International Classification for Diseases 10th Revision, were registered. During 756 054 person-years of follow-up, there were 559 deaths from total stroke, 258 from CHD, 1207 from total CVD and 4514 from total mortality for men, and for women, 494, 194, 1036 and 3092, respectively. Fruit intake was inversely associated with mortality from total stroke (the multivariable hazard ratio (HR (95 % CI)) in the highest v. lowest quartiles = 0.67 (0.55, 0.81)), total CVD (HR = 0.75 (0.66, 0.85)) and total mortality (HR = 0.86 (0.80, 0.92)). Vegetable intake was inversely associated with total CVD (HR = 0.88 (0.78, 0.99)). Bean intake was inversely associated with other CVD (HR = 0.79 (0.64, 0.98)), total CVD (HR = 0.84 (0.74, 0.95)) and total mortality (HR = 0.90 (0.84, 0.96)). Further adjustment for other plant-based foods did not alter the association of fruit intake with mortality from total stroke, total CVD and total mortality, but attenuated the associations of vegetables and beans with mortality risk. In conclusion, intakes of plant-based foods, particularly fruit intake, were associated with reduced mortality from CVD and all causes among Japanese men and women.
    The British journal of nutrition 02/2009; 102(2):285-92. · 3.45 Impact Factor
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    ABSTRACT: Limited evidence is available about the relations between sodium and potassium intakes and cardiovascular disease in the general population. The objective was to investigate relations between sodium and potassium intakes and cardiovascular disease in Asian populations whose mean sodium intake is generally high. Between 1988 and 1990, a total of 58,730 Japanese subjects (n = 23,119 men and 35,611 women) aged 40-79 y with no history of stroke, coronary heart disease, or cancer completed a lifestyle questionnaire including food intake frequency under the Japan Collaborative Cohort Study for Evaluation of Cancer Risk sponsored by the Ministry of Education, Sports and Science. After 745,161 person-years of follow-up, we documented 986 deaths from stroke (153 subarachnoid hemorrhages, 227 intraparenchymal hemorrhages, and 510 ischemic strokes) and 424 deaths from coronary heart disease. Sodium intake was positively associated with mortality from total stroke, ischemic stroke, and total cardiovascular disease. The multivariable hazard ratio for the highest versus the lowest quintiles of sodium intake after adjustment for age, sex, and cardiovascular disease risk factors was 1.55 (95% CI: 1.21, 2.00; P for trend < 0.001) for total stroke, 2.04 (95% CI: 1.41, 2.94; P for trend < 0.001) for ischemic stroke, and 1.42 (95% CI: 1.20, 1.69; P for trend < 0.001) for total cardiovascular disease. Potassium intake was inversely associated with mortality from coronary heart disease and total cardiovascular disease. The multivariable hazard ratio for the highest versus the lowest quintiles of potassium intake was 0.65 (95% CI: 0.39, 1.06; P for trend = 0.083) for coronary heart disease and 0.73 (95% CI: 0.59, 0.92; P for trend = 0.018) for total cardiovascular disease, and these associations were more evident for women than for men. A high sodium intake and a low potassium intake may increase the risk of mortality from cardiovascular disease.
    American Journal of Clinical Nutrition 07/2008; 88(1):195-202. · 6.50 Impact Factor
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    ABSTRACT: Previous studies have demonstrated the association between alcohol consumption and cardiovascular mortality. However, the sex-specific association between alcohol consumption and mortality from stroke and coronary heart disease remains unclear. Between 1988 and 1990, 34,776 men and 48 906 women aged 40 to 79 years completed a self-administered questionnaire including information about alcohol consumption. They were followed-up for a median duration of 14.2 years. Of the 83,682 respondents, 1628 died from stroke and 736 died from coronary heart disease. For men, heavy drinking (>or=46.0 g ethanol/day) was associated with increased mortality from total, hemorrhagic, and ischemic strokes, whereas light-to-moderate drinking was associated with reduced mortality from total cardiovascular disease, compared with not drinking. The respective multivariable hazard ratios (95% CI) were 1.48 (1.22 to 1.80) for total stoke, 1.67 (1.17 to 2.38) for hemorrhagic stroke, 1.35 (1.04 to 1.75) for ischemic stroke, and 0.88 (0.78 to 1.00) for total cardiovascular disease. Women who were heavy drinkers (>or=46.0 g ethanol/day) showed increased mortality from coronary heart disease, and there was reduced mortality from total cardiovascular disease for drinkers of 0.1 to 22.9 g ethanol per day compared with mortality for nondrinkers. The respective multivariable hazard ratios (95% CI) for the 2 categories of drinkers were 4.10 (1.63 to 10.3) and 0.75 (0.62 to 0.91). Heavy alcohol consumption is associated with increased mortality from total stroke, particularly hemorrhagic stroke, and total cardiovascular disease for men, and from coronary heart disease for women, whereas light-to-moderate drinking may be associated with reduced mortality from cardiovascular disease for both sexes.
    Stroke 07/2008; 39(11):2936-42. · 6.16 Impact Factor
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    ABSTRACT: Evidence is lacking regarding the relationship between cigarette smoking and breast cancer in Japanese women. We examined the association between breast cancer incidence and active and passive smoking in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. Our study comprised 34,401 women aged 40-79 years who had not been diagnosed previously with breast cancer and who provided information on smoking status at baseline (1988-1990). The subjects were followed from enrollment until December 31, 2001. Cox proportional-hazards models were used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between breast cancer incidence and tobacco smoke. During 271,412 person-years of follow-up, we identified 208 incident cases of breast cancer. Active smoking did not increase the risk of breast cancer, with a HR for current smokers of 0.67 (95% CI: 0.32-1.38). Furthermore, an increased risk of breast cancer was not observed in current smokers who smoked a greater number of cigarettes each day. Overall, passive smoking at home or in public spaces was also not associated with an increased risk of breast cancer among nonsmokers. Women who reported passive smoking during childhood had a statistically insignificant increase in risk (HR: 1.24; 95% CI: 0.84-1.85), compared with those who had not been exposed during this time. Smoking may not be associated with an increased risk of breast cancer in this cohort of Japanese women.
    Journal of Epidemiology 02/2008; 18(2):77-83. · 2.11 Impact Factor
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    ABSTRACT: The association between a lower incidence of breast cancer within the Asian population and the consumption of a diet high in soy has recently been the subject of much attention. To examine whether soy foods really have protective effects against breast cancer and how their influence on breast cancer is modified according to menopausal status, we conducted a population-based, prospective cohort study in Japan. We analyzed the data from the Japan Collaborative Cohort (JACC) Study. From 1988 to 1990, 30,454 women aged 40-79 years, completed a questionnaire on diet and other lifestyle features. Hazard ratios (HRs) were computed to examine the association between soy intake and the risk of breast cancer. During the mean follow-up of 7.6 years, 145 cases of breast cancer were documented. We found no significant association between the risk of breast cancer and consumption of tofu, boiled beans, and miso soup; the multivariate HRs (95% CI) in the highest category of consumption were 1.14 (0.74-1.77), 0.77 (0.47-1.27) and 1.01 (0.65-1.56), respectively. Only among postmenopausal women, we found no significant associations between soy foods and the risk of breast cancer. This prospective study suggests that consumption of soy food has no protective effects against breast cancer. Further large-scale investigations eliciting genetic factors may clarify different roles of various soybean-ingredient foods on the risk of breast cancer.
    Cancer Causes and Control 11/2007; 18(8):801-8. · 3.20 Impact Factor
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    ABSTRACT: The relation between serum total cholesterol and coronary heart disease is well established, but the relations with total stroke and stroke subtypes are controversial. We conducted a nested case-control study as part of the JACC study. A total of 39,242 subjects, 40-79 years of age, provided serum samples at baseline between 1988 and 1990. During the 10-year follow-up, 345 deaths from total strokes (including 76 intraparenchymal hemorrhages) and 150 deaths from coronary heart diseases were recorded. The control subjects were matched for sex, age, community, and year of serum storage, and further adjusted for systolic blood pressure, high density lipoprotein (HDL)-cholesterol, ethanol intake category, smoking status, and diabetes. Serum total cholesterol levels were measured using an enzymatic method. Cases with total stroke and more specifically intraparenchymal hemorrhage had lower mean values of serum total cholesterol levels compared with control subjects. The risk of mortality from intraparenchymal hemorrhage was significantly higher for persons with low total cholesterol levels [less than 4.14 mmol/l (160 mg/dl)] than with those with higher levels. The risk of mortality from coronary heart disease for persons with serum total cholesterol levels more than or equal to 6.72 mmol/l (260 mg/dl) was significantly higher than those with levels less than 4.14 mmol/l (160 mg/dl). Low serum total cholesterol levels are associated with high mortality from intraparenchymal hemorrhage while high levels are associated with high mortality from coronary heart disease among Japanese.
    Atherosclerosis 11/2007; 194(2):415-20. · 3.71 Impact Factor
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    ABSTRACT: There have been few systematic investigations into risk and protective factors for pneumonia related mortality for community residents. This study investigated these factors utilizing a large cohort study on Japanese community residents. Subjects, 110,792 individuals (aged 40-79 years) enrolled in 1988-1990, were followed until death, or when they moved away from the surveyed communities, or the end of 2003. Pneumonia death was defined following 480-486 (International Classification of Diseases, 9th Revision) or J12-J18 (10th Revision). Age-adjusted and multivariate hazard ratios were calculated along with 95% confidence intervals using the Cox proportional hazards model. With 1,112,747 person-years of the study, a total of 1,246 persons died of pneumonia. We found history of blood transfusion (multivariate hazard ratio=2.0 [95% confidence interval: 1.7-2.4]) was a potent novel risk factor. Walking 0.5-1 hour/day (0.8 [0.6-1.0]), 1+ hour/day (0.7 [0.6-0.8]), and/or a history of pregnancy (0.6 [0.4-0.9]) were found to reduce pneumonia mortality. A large body mass index (BMI) (25+kg/m(2)) was a protective factor (0.7 [0.5-0.8]), while low BMI (<18) was confirmed as a risk one (2.1 [1.7-2.6]). Smoking was an important preventable risk factor (1.6 [1.3-1.9], population attributable risk proportion=14%), and its cessation reduced risk (0.7 [0.5-1.0]) to levels comparable to neversmokers (0.7 [0.5-1.0]). The risk and protective factors ascertained here for pneumonia mortality among community residents, history of blood transfusion, large BMI, and walking habits, warrant further study. Smoking cessation may effectively reduce pneumonia mortality.
    Journal of Epidemiology 11/2007; 17(6):194-202. · 2.11 Impact Factor
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    ABSTRACT: To examine the association between psychological factors and the risk of breast cancer prospectively in a non-Western population. Data from the Japan Collaborative Cohort (JACC) study were analyzed. From 1988 to 1990, 34,497 women aged 40-79 years completed a questionnaire on medical, lifestyle and psychosocial factors. The rate ratios (RRs) of their responses were computed by fitting to proportional hazards models. During the mean follow-up period of 7.5 years, 149 breast cancer cases were documented. Those individuals who possessed "ikigai" (Japanese term meaning something that made one's life worth living) showed a significantly lower risk of breast cancer (multivariate-adjusted RR=0.66; 95% confidence interval [CI]=0.47-0.94). Those who perceived themselves as able to make decisions quickly also had a lower risk of breast cancer (multivariate-adjusted RR=0.56; 95% CI=0.36-0.87). The other factors investigated, including ease of anger arousal and self-perceived stress of daily life were not associated with breast cancer risk. Although further studies will be necessary to verify these findings, our results suggest that having "ikigai" and being decisive decrease an individual's subsequent risk of breast cancer.
    Cancer Causes and Control 05/2007; 18(3):259-67. · 3.20 Impact Factor
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    ABSTRACT: Early menopause is associated with increased risk of coronary heart disease in Caucasian women. However, this association has not been examined in Asian women. We conducted a 10-year cohort study of 37,965 Japanese post-menopausal women aged 40-79 years in the Japan Collaborative Cohort (JACC) Study. Causes of death were determined based on the International Classification of Disease. There were 487 mortality of stroke and 178 mortality of coronary heart disease. Late menarche or early menopause, or shorter duration of reproductive period was not associated with risk of mortality from coronary heart disease. However, compared with women with age at menarche < or =13 years, those with age at menarche > or =17 years tended to have increased risk of mortality from stroke: the multivariable hazard ratio was 1.32 (95% confidence interval [CI]: 0.93-1.87, p = 0.10). Compared with women with age at menopause of > or =49 years, those with age at menopause of <49 years tended to have increased risk of coronary heart disease among women aged 40-64 years; the multivariable hazard ratio was 1.85 (95% CI: 0.92-3.73, p = 0.08). The possible association between early menopause and coronary heart disease among middle-aged women was consistent with the result of observational studies for Caucasian women, and can be explained by a protective effect of endogenous estrogen on the development of atherosclerosis.
    Journal of Epidemiology 09/2006; 16(5):177-84. · 2.11 Impact Factor
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    ABSTRACT: The association between serum uric acid (UA) and the prevalence of hypertension, and the relationship between methylenetetrahydrofolate reductase (MTHFR) polymorphism and hypertension remains unclear. The aim of the present study was to investigate whether the C677T MTHFR mutation genotype (VV) is independently associated with the prevalence of hypertension or blood pressure (BP), and examined any interaction of MTHFR and UA with BP. Participants were randomly selected from all residents (aged 40-69 years) in a rural county of Japan, and the data for the men (n=335) were analyzed. ;Hypertension' was defined as systolic BP >or=140 and/or diastolic BP >or=90 mmHg and/or being administered antihypertensive medication. Serum UA level was independently associated with the prevalence of hypertension (odds ratio (95% confidence interval) =2.7 (1.2-5.9), p=0.047) for the highest tertile of serum UA (>or=398.5 micromol/L (6.7 mg/dl)) vs that of the lowest tertile (<321.2 micromol/L (5.4 mg/dl)), but the MTHFR mutation was not independently associated with prevalence of hypertension or BP. No interaction of the MTHFR mutation and serum UA with BP was found. The mutation of C677T MTHFR was not independently associated with the prevalence of hypertension or BP levels although serum UA was. Furthermore, the relationship between serum UA and BP was not modulated by the MTHFR mutation in Japanese men.
    Circulation Journal 02/2006; 70(1):83-7. · 3.58 Impact Factor
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    ABSTRACT: No prospective studies have examined the association between calcium intake and the risk of cardiovascular disease in Japanese populations with a low mean calcium intake. Between 1988 and 1990, 110,792 Japanese subjects (46,465 men and 64,327 women) 40 to 79 years of age without a history of stroke, coronary heart disease, or cancer, completed a lifestyle questionnaire including food intake frequency under the Japan Collaborative Cohort (JACC) Study for Evaluation of Cancer Risk Sponsored by Monbusho. By the end of 1999, after 515,029 person years of follow-up, 566 deaths from stroke (101 subarachnoid hemorrhages, 140 intraparenchymal hemorrhages, and 273 ischemic strokes) and 234 deaths from coronary heart disease had been documented. The intake of total calcium tended to be inversely associated with mortality from total stroke but not from coronary heart disease or total cardiovascular disease for men and women. The inverse association with dairy calcium intake was apparent for total stroke, both hemorrhagic and ischemic. The multivariate relative risk for men with highest versus lowest quintiles of dairy calcium intake was 0.53 (95% CI, 0.34 to 0.81) for total stroke, 0.46 (0.23 to 0.91) for hemorrhagic stroke, and 0.53 (0.29 to 0.99) for ischemic stroke; corresponding relative risks for women were 0.57 (0.38 to 0.86), 0.51 (0.28 to 0.94), and 0.50 (0.27 to 0.95). Dietary calcium intake from dairy products was associated with reduced mortality from stroke for Japanese men and women.
    Stroke 02/2006; 37(1):20-6. · 6.16 Impact Factor
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    ABSTRACT: We aimed to examine the impact of exercise on mortality from cardiovascular disease (CVD) in Asian populations. Few data have been available in Asian countries, where job-related physical activity is higher than that in Western countries. Between 1988 and 1990, 31,023 men and 42,242 women in Japan, ages 40 to 79 years with no history of stroke, coronary heart disease (CHD), or cancer, completed a self-administered questionnaire. Systematic mortality surveillance was performed through 1999, and 1,946 cardiovascular deaths were identified. We chose the second lowest categories of walking and sports participation as the reference to reduce a potential effect of ill health. Men and women who reported having physical activity in the highest category (i.e., walking > or =1 h/day or doing sports > or =5 h/week) had a 20% to 60% lower age-adjusted risk of mortality from CVD, compared with those in the second lowest physical activity category (i.e., walking 0.5 h/day, or sports participation for 1 to 2 h/week). Adjustment for known risk factors, exclusion of individuals who died within two years of baseline inquiry, or gender-specific analysis did not substantially alter these associations. The multivariate-adjusted hazard ratios (95% confidence interval) for the highest versus the second lowest categories of walking or sports participation were 0.71 (0.54 to 0.94) and 0.80 (0.48 to 1.31), respectively, for ischemic stroke (IS); 0.84 (0.64 to 1.09) and 0.51 (0.32 to 0.82), respectively, for CHD; and 0.84 (0.75 to 0.95) and 0.73 (0.60 to 0.90), respectively, for CVD. Physical activity through walking and sports participation might reduce the risk of mortality from IS and CHD.
    Journal of the American College of Cardiology 12/2005; 46(9):1761-7. · 14.09 Impact Factor
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    ABSTRACT: To examine the possible association of dietary fat and fatty acids with breast cancer risk in a population with a low total fat intake and a high consumption of fish, we analyzed data from the Japan Collaborative Cohort (JACC) Study. From 1988 to 1990, 26 291 women aged 40-79 years completed a questionnaire on dietary and other factors. Intakes of fat or fatty acids were estimated by using a food frequency questionnaire. Rate ratios (RR) were computed by fitting proportional hazards models. During the mean follow-up of 7.6 years, 129 breast cancer cases were documented. We found no clear association of total fat intake with breast cancer risk; the multivariate-adjusted RR across quartiles were 1.00, 1.29, 0.95, and 0.80 (95% confidence interval [CI] 0.46-1.38). A significant decrease in the risk was detected for the highest quartile of intake compared with the lowest for fish fat and long-chain n-3 fatty acids; the RR were 0.56 (95% CI 0.33-0.94) and 0.50 (0.30-0.85), respectively. A decreasing trend in risk was also suggested with an increasing intake of saturated fatty acids (trend P = 0.066). Among postmenopausal women at baseline, the highest quartile of vegetable fat intake was associated with a 2.08-fold increase in risk (95% CI 1.05-4.13). This prospective study did not support any increase in the risk of breast cancer associated with total or saturated fat intake, but it suggested the protective effects of the long-chain n-3 fatty acids that are abundant in fish.
    Cancer Science 10/2005; 96(9):590-9. · 3.48 Impact Factor
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    ABSTRACT: The incidence of ovarian cancer in Japan has increased since the 1970s. The many studies that have assessed the relationship between body mass index (BMI) and the risk of ovarian cancer have produced contradictory results. Here we investigated this relation using data from the Japan Collaborative Cohort Study for the Evaluation of Cancer Risk, which was initiated in 1988. A self-administered questionnaire on dietary habits and other risk factors for cancer was completed by 36,456 Japanese women. After 7.6 years of follow up, 38 cases of ovarian cancer were available for analysis. Cox proportional-hazards models were used to compute relative risks and to adjust for confounders. Compared to women with BMI of 18.5-24.9 kg/m2, the relative risk of ovarian cancer was 2.24 (95% CI = 1.10-4.21) for BMI of 25.0-29.9 and 1.78 (95% CI = 0.24-13.34) for BMI of > or = 30 kg/m2. A test for trend revealed that this finding was statistically significant (P = 0.014). The results of this study suggest that being overweight is independently associated with a higher risk of developing ovarian cancer in the Japanese population.
    Journal of Obstetrics and Gynaecology Research 10/2005; 31(5):452-8. · 0.84 Impact Factor
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    ABSTRACT: Epidemiologic evidence is lacking for the association between alcohol consumption and the risk of breast cancer in Japanese women. We addressed this association in a prospective cohort study with an average follow-up of 7.6 years. At baseline (1988-1990), cohort participants completed a self-administered questionnaire that included alcohol use, reproductive history and hormone use. The women were followed up for breast cancer incidence through December 31, 1997. Cox proportional hazards models were used to calculate relative risks (RRs) and 95% confidence intervals (CIs) for breast cancer incidence and any association with alcohol consumption. During a follow-up of 271,412 person-years, we identified 151 women with breast cancer, of whom 45 were current drinkers and 11 drank > or =15 g of alcohol/day. After adjustment for age and other potential risk factors for breast cancer, the RR for current drinkers was 1.27 (95% CI 0.87-1.84) compared to nondrinkers. Average alcohol intake of <15 g/day did not significantly increase the risk for breast cancer. However, risk was significantly increased for women who consumed > or =15 g/day of alcohol (RR = 2.93, 95% CI 1.55-5.54). Age at starting drinking and frequency of consumption per week were not significantly associated with breast cancer risk. Our cohort study demonstrated that Japanese women who consume at least a moderate amount of alcohol have an increased risk of breast cancer.
    International Journal of Cancer 09/2005; 116(5):779-83. · 6.20 Impact Factor
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    ABSTRACT: Although overweight is an important risk factor for cardiovascular disease in Western countries, the impact of overweight has not been well elucidated in Japan, where its prevalence is low. A total of 104,928 Japanese (43,889 men and 61,039 women) aged 40 to 79 years, free of stroke, coronary heart disease, and cancer at entry participated in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk Sponsored by Monbusho (JACC Study) between 1988 and 1990. Systematic surveillance was completed until the end of 1999, with 1,042,835 person years of follow-up, and the underlying causes of death were determined based on the International Classification of Diseases. There were 765 total strokes (191 intraparenchymal hemorrhages), 379 coronary heart diseases, and 1707 total cardiovascular diseases for men; and for women, there were 685 (145), 256, and 1432, respectively. Compared with persons with body mass index (BMI) 23.0 to 24.9, those with BMI > or =27.0 kg/m2 had a higher risk of coronary heart disease; for men and women, the respective multivariate relative risk (95% CI) was 2.05 (1.35 to 3.13) and 1.58 (0.95 to 2.62). Persons with BMI <18.5 kg/m2 had higher risk of total stroke and intraparenchymal hemorrhage, for men and women, the respective multivariate relative risk was 1.29 (1.01 to 1.49) and 1.92 (1.49 to 2.47) for total stroke and 1.96 (1.16 to 3.31) and 2.32 (1.36 to 3.97) for intraparenchymal hemorrhage. These excess risks did not alter materially when deaths within 5 years were excluded or when smoking status was taken into account. For Japanese men and women, high BMI was associated with increased risk of coronary heart disease, whereas low BMI was associated with intraparenchymal hemorrhage.
    Stroke 08/2005; 36(7):1377-82. · 6.16 Impact Factor
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    ABSTRACT: Elevated mean corpuscular volume (MCV) is a traditional biological marker for alcohol abuse and alcoholism, but the underlying mechanism is unclear. Three recent epidemiologic studies consistently showed that MCV was elevated by alcohol drinking more markedly among individuals with genetically inactive aldehyde dehydrogenase-2 (ALDH2) (encoded by ALDH2*2 mutant allele) than those with active ALDH2 (encoded by ALDH2*1/2*1 genotype), suggesting that the elevated MCV was etiologically linked to acetaldehyde exposure. The purpose of the present study was to clarify further this relationship by examining the status of folate and vitamin B12. The study participants were 159 men who were aged 40 to 69 years and randomly selected from a Japanese rural population. The genetic polymorphism of ALDH2 was determined by PCR-restriction fragment length polymorphism method; data on alcohol drinking and other lifestyles were collected using a structured questionnaire; serum concentrations of folate and vitamin B12 were measured using the protein competitive reaction method, and blood cell counts were measured by routine methods. A multiple linear regression model was used to analyze the data. : The relationship between alcohol drinking and serum folate concentration was significantly different between ALDH2 genotypes, indicating that the reduction of serum folate by alcohol drinking was more marked in men with ALDH2*1/2*2 than those with ALDH2*1/2*1. The relationship between alcohol drinking and elevated MCV was significantly stronger in men with ALDH2*1/2*2 than those with ALDH2*1/2*1 even after adjustment for serum folate and vitamin B12 concentrations. These findings indicate that acetaldehyde plays a significant role in the development of decreased serum folate concentration and elevated MCV by alcohol drinking.
    Alcoholism Clinical and Experimental Research 05/2005; 29(4):622-30. · 3.42 Impact Factor
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    ABSTRACT: The many studies into the relation between cigarette smoking and the risk of ovarian cancer have produced inconsistent results. Here we investigated this relation using data from the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, initiated in 1988. A self-administered questionnaire on smoking habits and other risk factors for cancer was completed by 34 639 Japanese women. After 7.6 years of follow up, 39 cases of ovarian cancer were available for analyses. Cox proportional-hazards models were used to compute relative risks (RR) and to adjust for confounders. Relative to those who had never smoked, the RR of ovarian cancer were 1.63 (95% confidence interval [CI] = 0.21-12.50) for former smokers and 2.27 (95% CI = 0.85-6.08) for current smokers. Among current smokers, the RR were 1.48 (95% CI = 0.20-10.92), 5.56 (95% CI = 1.68-19.06), and 1.86 (95% CI = 0.25-14.30) among women who smoked <10, 10-19, and at least 20 pack-years ([number of cigarettes smoked per day/20] x number of years subject has smoked), respectively, relative to those who had never smoked. A test for trend was statistically significant (P = 0.044). These data indicate that cigarette smoking increases the risk of developing ovarian cancer in the Japanese population.
    Journal of Obstetrics and Gynaecology Research 05/2005; 31(2):144-51. · 0.84 Impact Factor

Publication Stats

812 Citations
125.63 Total Impact Points

Institutions

  • 2005–2010
    • University of Tsukuba
      • Institute of Community Medicine
      Tsukuba, Ibaraki-ken, Japan
    • Mukogawa Women's University
      • Department of Food Science and Nutrition
      Japan
    • National Institute of Public Health
      Saitama, Saitama, Japan
  • 2009
    • Kyoto Prefectural University of Medicine
      • Department of Social Medicine and Cultural Sciences
      Kioto, Kyōto, Japan
    • Kyoto University
      • Department of Health and Environmental Sciences
      Kyoto, Kyoto-fu, Japan
  • 2005–2009
    • Hyogo Prefectural Institute of Public Health and Consumer Sciences
      Kōbe, Hyōgo, Japan
  • 2008
    • Osaka University
      • Department of Social and Environmental Medicine
      Ōsaka-shi, Osaka-fu, Japan
  • 2005–2008
    • Aichi Medical University
      • Department of Public Health
      Okazaki, Aichi, Japan
  • 2005–2007
    • Nagoya University
      Nagoya, Aichi, Japan
    • Aichi Cancer Center
      Ōsaka, Ōsaka, Japan
  • 2006
    • National Institute of Health and Nutrition
      Edo, Tōkyō, Japan
  • 2003
    • Tokyo Medical and Dental University
      • Department of Epidemiology
      Edo, Tōkyō, Japan