Kazuo Wakabayashi

Coffee consumption and serum aminotransferases in middle-aged Japanese men

We investigated the relation between coffee drinking and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations among 7313 Japanese men receiving a health examination, excluding former alcohol drinkers and men with a history of chronic liver disease. Serum AST > 40 and/or ALT > 40 U/L was defined as liver inflammation. Adjustment was made for alcohol use, smoking, body mass index, serum marker for hepatitis virus infection, and other possible confounders. Adjusted odds ratios of liver inflammation were 1.00 (reference), 0.80, 0.69, and 0.61 for men drinking < 1, 1-2, 3-4, and > or = 5 cups of coffee daily, respectively. Among 6898 men without liver inflammation, serum AST and ALT were inversely associated with coffee consumption, and alcohol-related rise in AST was attenuated with coffee drinking. These findings suggest coffee may have an effect of suppressing the rise of serum aminotransferase, partly by inhibiting the alcohol-related elevation. Studies regarding biological mechanism are warranted.

Gallstone disease among Japanese men in relation to obesity, glucose intolerance, exercise, alcohol use, and smoking

BACKGROUND Risk factors for gallstones are not fully understood, especially in men. Obesity and other risk factors for gallstone disease were investigated in Japanese men based on gallbladder ultrasonography. METHODS Forty-one men with gallstones, 31 with postcholecystectomy state, and 2044 with a normal gallbladder were identified among 2228 men aged 49-55 years who received a retirement health examination at three hospitals of the Japan Self-Defense Forces between 1991 and 1992. Glucose tolerance was determined with a 75-g oral glucose tolerance test. RESULTS Body mass index was not associated with gallstones, although it was significantly, positively related to postcholecystectomy. Waist to hip circumference ratio tended to be weakly associated with gallstones. Diabetes mellitus was associated only with postcholecystectomy. Smoking, alcohol intake, and physical activity were not measurably related to either gallstones or postcholecystectomy. CONCLUSIONS The present study failed to substantiate an association of gallstone risk with either obesity or any other risk factor. Further observation is needed in view of the limited study power.

Coffee Drinking and Serum Gamma-Glutamyltransferase: An Extended Study of Self-Defense Officials of Japan

PURPOSE To examine the effect of coffee drinking on serum gamma-glutamyltransferase (GGT) level in relation to alcohol drinking, smoking, and degree of obesity in middle-aged Japanese men. METHODS From 1986 to 1994, a total of 7,637 male officials of the Self-Defense Forces of Japan aged 48-59 years received a preretirement health examination. Coffee drinking was ascertained by a self-administered questionnaire, and serum GGT level was measured. After excluding 1,360 men with a possible pathologic condition influencing liver enzyme levels and 182 former alcohol drinkers, effect of coffee drinking on serum GGT was examined by a multiple linear regression model and analysis of variance adjusting for alcohol drinking, smoking, and body mass index (BMI). RESULTS The adjusted percentage of difference in serum GGT was -4.3 (95% CI = -5.0; -3.5) per cup of coffee. The inverse coffee-GGT relation was most prominent among men drinking > or = 30 ml of ethanol and smoking > or = 15 cigarettes daily; and positive associations of alcohol and smoking with GGT were attenuated by coffee drinking, more clearly among men with BMI > or = 25.00 kg/m2. Adjusted percentages of difference in serum GGT were -2.6% (p = 0.0003) per cup of brewed coffee, and -5.1% (p = 0.0001) per cup of instant coffee, independently of each other. CONCLUSIONS The present study suggests that coffee consumption may weaken GGT-induction by alcohol, and possibly by smoking. These effect modifications by coffee may differ according to the degree of obesity.

The Relation of Smoking, Alcohol Use and Obesity to Risk of Sigmoid Colon and Rectal Adenomas

We conducted a case‐control study, using 429 cases with histologically confirmed sigmoid adenoma, 75 cases with rectal adenoma, and 3101 controls showing normal colonoscopy at least up to 60 cm from the anus. The subjects were male Self‐Defense Forces personnel aged 48–56 who received a retirement health examination including a routine sigmoid‐ or colonoscopy. Lifestyle characteristics were ascertained by a self‐administered questionnaire. Smoking in the recent past (ġ 10 years preceding the colonoscopy) and smoking in the remote past (>10 years before the colonoscopy) were both significantly associated with risk of sigmoid adenoma but not with rectal adenoma as a whole. After reciprocal adjustment for smoking in the two periods, only smoking in the recent past was associated with both sigmoid colon and rectal adenomas. Odds ratios (OR) of sigmoid adenoma (and 95% confidence interval) for the categories of 0, 1‐150, 151‐250 and ġ251 cigarette‐years were 1.0 (reference), 1.9 (1.3‐2,8), 2.1 (1.4‐3.0) and 3.0 (1.9‐4.7), respectively (P for trend < 0.01), and those for rectal adenoma were 1.0 (reference), 1.2 (0.4‐3.2), 3.5 (1.4‐8.5) and 2.0 (0.6‐6.7), respectively (P for trend = 0.03). Alcohol use was significantly positively associated with sigmoid adenoma, and insignificantly associated with rectal adenoma. Body mass index was significantly positively associated with sigmoid adenoma, especially large ones. No such association was found for rectal adenoma. These findings suggest that smoking, especially in the recent past, and alcohol use are common risk factors for sigmoid colon and rectal adenomas while obesity may be exclusively related to the growth of sigmoid adenoma.

Relation of total and beverage-specific alcohol intake to body mass index and waist-to-hip ratio: A study of self-defense officials in Japan

We investigated the independent associations of total and beverage-specific ethanol consumption with body mass index (BMI) and waist-to-hip ratio (WHR) in middle-aged Japanese males, because of the scarcity of epidemiologic data in Japan. The subjects were 2227 male self-defense officials who received a pre-retirement health examination at the Self-Defense Forces Fukuoka, Kumamoto, and Sapporo Hospitals. Data on alcohol intake, smoking, physical activity, and past medical history were obtained from a self-reported questionnaire. Height, weight, and waist and hip girth measurements were obtained at the examination. Multiple linear regression analysis was employed. Alcohol intake was positively and strongly associated with WHR (p = 0.0001), but not associated with BMI after adjustment for lifestyle variables, including either BMI or WHR. Subjects who consumed 15 ml per day or more of shochu ethanol showed a larger WHR than never drinkers, and a dose-response relationship was found. Dose-response relationships to other beverages were not found. Dose-response relationships to other beverages were not found. These findings suggest that alcohol intake is strongly and independently associated with WHR, but not with BMI. Abdominal obesity was positively associated with shochu ethanol, but not with other types of alcohol.

Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan

The study aims to examine the relationship between habitual coffee consumption and blood pressure. The subjects were 3336 male self-defense officials aged 48–56 years, who received a preretirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1992. Average coffee intake in the past year was ascertained by a self-administered questionnaire. A significant inverse relation between habitual coffee consumption and blood pressure was found with and without adjustment for alcohol use, cigarette smoking, body mass index, glucose tolerance, and green tea intake. Green tea, another major source of caffeine intake in Japanese, was unrelated to blood pressure. The adjusted mean differences per cup of coffee consumed per day were −0.6 mmHg (95% confident interval [CI]: −0.9 to −0.3, p=0.0001) in systolic blood pressure and −0.4 mmHg (95% CI: −0.5 to −0.2, p=0.0002) in diastolic blood pressure. Habitual coffee drinkers had lower blood pressure than non-drinkers at any levels of alcohol use, cigarette smoking, obesity, and glucose intolerance. Our findings consolidate the previous observation that habitual coffee consumption was associated with lower blood pressure.

Gallstone disease risk in relation to body mass index and waist-to-hip ratio in Japanese men

OBJECTIVE: To examine the relation of body mass index (BMI) and waist-to-hip ratio (WHR) to gallstones and postcholecystectomy risk in middle-aged Japanese men.DESIGN: Cross-sectional study.SUBJECTS: We used 174 men with prevalent gallstones, 104 with postcholecystectomy and 6909 with normal gallbladder in the consecutive series of 7637 men aged 48–59 y receiving a preretirement health examination at four hospitals of the Japan Self-Defense Forces between 1986 and 1994.MEASUREMENTS: Gallbladder status was assessed by abdominal ultrasonography after an overnight fast. BMI was calculated as weight in kilogram divided by height in square meters, and WHR was used as a measure of central obesity. Analysis of the WHR was limited to a subset of data for the period 1991–1994 (gallstones 113, postcholecystectomy 66 and normal gallbladder 4410).RESULTS: After adjustment for hospital, rank in the Self-Defense Forces, cigarette smoking, alcohol use and glucose tolerance, BMI was significantly associated with an increased risk of both prevalent gallstones and postcholecystectomy. WHR also showed a significant positive association with each of the two conditions. When BMI and WHR were mutually adjusted for, both of the obesity indices tended to be associated positively with prevalent gallstones and postcholecystectomy.CONCLUSION: These findings indicate that obesity is associated with increased gallstone risk in men.

Relationship of Cigarette Smoking, Alcohol Use, and Dietary Habits with Sigmoid Colon Adenomas

The relationship between cigarette smoking, alcohol use, and dietary factors and the risk of adenomas of the sigmoid colon was examined in male self-defense officials who received a preretirement health examination at three Self-Defense Forces hospitals in Japan. In the comparison between 228 patients with sigmoid adenomas and 1484 control subjects with normal colonoscopy findings (> or = 60 cm from the anus), a clear dose-response relationship was observed between cigarette smoking and risk of adenoma. After adjustment for rank, body mass index, alcohol use, and physical activity as well as for hospital and survey season, the odds ratios (and 95% confidence intervals (CIs)) for the categories of 0, 1 to 399, 400 to 799, and 800 or more cigarette-years were 1.0, 2.1 (1.2 to 3.5), 2.8 (1.8 to 4.3), and 3.5 (2.1 to 5.8), respectively. Current alcohol drinkers tended to have an increased risk, but without a dose-response relation. Among four types of alcoholic beverages (shochu, sake, beer, and whiskey), only whiskey showed a weak association with risk of adenoma. None of the 13 dietary items studied (including meat and rice consumption) was measurably associated with adenoma risk. The present findings provide additional evidence that cigarette smoking is a risk factor for colon adenomas. It is inconclusive regarding alcohol intakes association with adenoma risk.

Impaired glucose tolerance, diabetes mellitus, and gallstone disease: An extended study of male self-defense officials in Japan

Few studies have investigated the relation between glucose tolerance status and ultrasonographically determined gallstone disease. Using a 75-g oral glucose tolerance test, we examined the association of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) with gallstone disease in Japanese men. Subjects were men aged 48 to 59 of the Japan Self-Defense Forces who received a preretirement health examination between October 1986 to December 1994. After exclusion of 12 men under insulin treatment in the consecutive series of 7637 men, 174 were found to have gallstones; 103 were at the state of postcholecystectomy, and 6899 had normal gallbladder. IGT and NIDDM were associated with a modestly increased risk of gallstone disease; adjusted odds ratios were 1.3 (95% confidence interval [CI]: 0.9–1.8) for IGT and 1.3 (95% CI: 0.8–2.0) for NIDDM after adjustment for hospital, rank, smoking, alcohol use, and body mass index. Adjusted odds ratio for IGT and NIDDM combined was 1.3 (95% CI: 1.0–1.7, p=0.08). When prevalent gallstones and postcholecystectomy were considered separately, NIDDM showed a significant, positive association with postcholecystectomy, but not with prevalent gallstones. The findings add to evidence that glucose intolerance is associated with a modest increase in the risk of gallstone disease.