Tomoki Kawano

Relation between green tea consumption and the severity of coronary atherosclerosis among Japanese men and women

PURPOSE To examine the relation between green tea consumption and arteriographically determined coronary atherosclerosis. METHODS Study subjects were 512 patients (302 men and 210 women) aged 30 years or older who underwent coronary arteriography for the first time at four hospitals in Fukuoka City or one hospital in an adjacent city between September 1996 and August 1997. Lifestyle characteristics including green tea consumption were ascertained before arteriography by a questionnaire supported with interview. RESULTS 117 men (38.7%) and 50 women (23.8%) had significant stenosis of one or more coronary arteries. Green tea consumption tended to be inversely associated with coronary atherosclerosis in men, but not in women. An evident, protective association between green tea and coronary atherosclerosis was observed in a subgroup of 262 men excluding those under dietary or drug treatment for diabetes mellitus. In this subgroup, after adjustment for traditional coronary risk factors and coffee, odds ratios of significant stenosis for consumption of 2-3 cups and 4 or more cups per day were 0.5 (95% confidence interval 0.2-1.2) and 0.4 (0.2-0.9), respectively, as compared with a consumption of one cup per day or less. CONCLUSIONS The results indicate that green tea may be protective against coronary atherosclerosis at least in men.

Obesity, body fat distribution and coronary atherosclerosis among Japanese men and women

OBJECTIVE: To investigate the relation of the obesity and body-fat distribution with angiographically defined coronary atherosclerosis.DESIGN: Cross-sectional study in a clinical setting.SUBJECTS: Three hundred and twenty men (median age, 59 y) and 212 women (median age, 67 y) who underwent coronary angiography for suspected or known coronary heart disease at 5 cardiology departments between September 1996 and August 1997. Patients with disease duration >1 y were excluded.MEASUREMENTS: The body mass index (BMI) and the waist to hip circumference ratio (WHR) were used as main exposure variables, and either the presence of significant coronary stenosis or the Gensinis score (≥10 vs<10) as an outcome variable, in a sex-specific multiple logistic regression analysis controlling for age, hospital, and other coronary risk factors.RESULTS: Among male patients, BMI was progressively higher with an increasing number of vessels involved (P trend=0.05); the adjusted odds ratios for the presence of significant stenosis across quartiles of BMI were 1.0 (reference), 1.1, 1.9 and 2.5 (P trend=0.02), and the positive association was more pronounced for younger patients. Among females, however, such associations were not evident. Employing the Gensinis score as an outcome gave similar results. WHR was not significantly associated with either outcome regardless of sex.CONCLUSION: These results suggested that BMI was predictive of coronary stenosis among male patients, but not among female patients. Unlike most previous studies, this study failed to detect a positive association with WHR.

Job strain, Type A behavior pattern, and the prevalence of coronary atherosclerosis in Japanese working men

OBJECTIVE To examine the relation of type A behavior pattern and job strain to angiographically documented coronary stenosis. METHODS Subjects were 197 male Japanese patients with a full-time job. A questionnaire-based interview elicited psychosocial and other factors. Type A behavior pattern was measured by 12 questions, and job strain by the method of Karasek. Significant coronary stenosis was defined when a 75% or greater luminal narrowing occurred at one or more major coronary arteries or when a 50% or greater narrowing occurred at the left main artery. Logistic regression analysis was used to calculate odds ratio (OR) and 95% confidence interval (CI) with adjustment for traditional coronary risk factors and job type. RESULTS Type A behavior pattern was related to a statistically non-significant lower prevalence of the coronary stenosis especially in the absence of job strain (adjusted OR 0.6, 95% CI 0.3-1.2). Job strain was non-significantly associated with a modestly increased prevalence of coronary stenosis (OR 1.7, 95% CI 0.6-5.2). CONCLUSION These findings suggest that both the behavioral pattern and psychosocial work environment may be related to coronary artery stenosis.

Alcohol consumption and severity of angiographically determined coronary artery disease in Japanese men and women.

The relation of alcohol consumption to the severity of coronary atherosclerosis was examined among 323 men and 220 women who underwent coronary arteriography. Severity of coronary atherosclerosis was assessed by the number of vessels obstructed > or =75% in diameter and Gensinis severity score. Alcohol consumption was divided into 5 categories in men (never, past, 1-24, 25-49, and > or =50 ml per day) and 3 categories in women (never, past, and current). Among men, odds ratios of severe stenosis (multiple-vessel disease or Gensinis score >15) decreased substantially and significantly in all current drinking categories but without dose-response effect. There was a weak, inverse association of current alcohol consumption with one-vessel disease, but not with moderate stenosis in terms of Gensinis score (< or =15). Past drinkers showed a fairly large, but statistically nonsignificant, decrease in the odds ratios of not only severe stenosis but also of moderate stenosis. Among women, current drinkers showed a small, statistically nonsignificant decrease in the risk of severe stenosis in terms of Gensinis score. These associations with alcohol use did not change after adjustment for known coronary risk factors. The present findings add to evidence that alcohol drinking confers protection against coronary atherosclerosis.

Relation between type A behavior pattern and the extent of coronary atherosclerosis in Japanese women.

This study examined the relation of Type A behavior pattern and its components to angiographically documented coronary atherosclerosis in 198 Japanese women. A questionnaire-based interview elicited psychosocial and other factors. Type A behavior pattern was measured by 12 questions. Significant coronary stenosis was defined when a 75% or greater luminal narrowing occurred atoneor more major coronary arteries or 50% or greater narrowing occurred at the left main artery. Gensini’s score also was calculated. Logistic regression analysis was used to calculate odds ratios and 95% confidence intervals with adjustment for traditional coronary risk factors and the presence of a job. Global Type A behavior pattern showed no material association with the severity of coronary atherosclerosis assessed by both Gensini’s score and the presence of significant coronary stenosis. However, its subcomponents, enthusiasm and competitiveness, were positively related to the severity of coronary atherosclerosis, whereas self-confidence and perfectionism were negatively related. These findings suggest overall a null association between global Type A and coronary atherosclerosis as well as the presence of toxic or beneficial components of Type A behaviors in Japanese women.