Takesumi Yoshimura

Dietary factors and stomach cancer mortality

The present study examined the relationship between stomach cancer and the low intake of fresh fruit and vegetables and/or a high intake of pickled, preserved or salted foods and frequent use of cooking oil. During 139 390 person–year of follow-up of over 13 000 subjects, 116 died from stomach cancer. Using a Cox proportional hazards–regression analysis of relative risk (RR, 95% CI) controlling for age, sex, smoking and other dietary factors, a significant decline was found with a high consumption of green and yellow vegetables (RR=0.4, 95% CI=0.2–0.9). Reductions of between 40 and 50% were also observed with a high consumption of fresh foods (fruit, cuttle fish, tofu, and potatoes), but these associations were not statistically significant. The risk was significantly increased by the high consumption of processed meat (RR=2.7, 95% CI=1.0-7.4) and by the frequent use of cooking oil (RR=4.0, 95% CI=1.3-11.8). The high consumption of pickled food and traditional soups also increased risk, but not significantly. The findings suggest that a diet high in salt and low in vitamins may be associated with an increase in stomach cancer.

Marital status and mortality among Japanese men and women: the Japan Collaborative Cohort Study.

BackgroundSeveral studies have indicated a significant association between marital status and mortality risks. However, most of these studies have compared married and unmarried people without differentiating among single, divorced and widowed status. Moreover, gender differences in mortality rates associated with marital status have not been sufficiently clarified. With significant increases in the percentages of divorced and widowed people and a corresponding drop in the marriage rate in Japan during the past two or three decades, it can be expected that these changes will have a significant impact on mortality rates.MethodsThis investigation used a prospective study of a total of 94,062 Japanese men and women aged 40–79 who completed self-administered questionnaires at baseline and during a followed-up of 9.9-years.ResultsCompared with married men, never-married men showed higher risks of mortality from cardiovascular disease [relative risk (RR) = 3.05, 95% confidence interval (CI) 2.03–4.60], respiratory disease (RR = 2.43, 95%CI 1.27–4.63), external causes (RR = 2.18, 95%CI 1.05–4.54) and all causes (RR = 1.91, 95%CI 1.51–2.42) after adjustment for potentially confounding variables. For never-married women, there was a smaller but significantly higher risk of mortality from all causes (RR = 1.46, 95%CI 1.15–1.84). Divorced and widowed men showed moderately higher risks of mortality from cardiovascular disease, external causes and all causes compared with married men, but such a trend was not observed in women.ConclusionSingle status was associated with a higher risk of mortality than was married status for both men and women. Divorce and widowhood were associated with elevated risk for men, but not for women. These findings suggest single, divorce and widowhood status constitute potentially adverse health effects.

Arsenic contamination of groundwater and prevalence of arsenical dermatosis in the Hetao plain area, Inner Mongolia, China

An investigation was carried out on arsenic contamination of groundwater and prevalence of arsenical dermatosis in the Hetao plain of Inner Mongolia Autonomous Region, China. Based on the screening of water samples from 96 randomly selected wells in this Region, two areas (Wuyuan and Alashan) were chosen as highly contaminated areas because arsenic in the water samples was higher than 50 μg/l. Arsenic was measured using an arsenic silver diethyl dithiocarbamate method for 326 water samples from all the wells in these areas. The results show arsenic contaminated groundwater from tubule‐type wells of depths about 15–30 m was serious compared with open-type wells where depth is about 3–5 m. In the Wuyuan area, 96.2% of water samples from tubule-type wells contained arsenic above 50 μg/l and 69.3% in Alashan area; the highest value was 1354 μg/l and 1088 μg/l, respectively. In these two areas, a health survey was carried out for arsenical dermatosis. The results show the prevalence of arsenical dermatosis in the Wuyuan area was 44.8%, higher than 37.1% prevalence of arsenical dermatosis in the Alashan area. The prevalence of arsenical dermatosis was highest in the over 40‐year‐old age group. There was no sex difference in the prevalence. Further investigation is needed to clarify the actual situation of arsenic pollution of groundwater in Inner Mongolia, China in order to reduce the adverse health effect among residents exposed to arsenic.

Coffee and risk of death from hepatocellular carcinoma in a large cohort study in Japan.

We examined the relation between coffee drinking and hepatocellular carcinoma (HCC) mortality in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study). In total, 110 688 cohort members (46 399 male and 64 289 female subjects) aged 40–79 years were grouped by coffee intake into three categories: one or more cups per day, less than one cup per day and non-coffee drinkers. Cox proportional hazards model by SAS was used to obtain hazard ratio of HCC mortality for each coffee consumption categories. The hazard ratios were adjusted for age, gender, educational status, history of diabetes and liver diseases, smoking habits and alcohol. The hazard ratio of death due to HCC for drinkers of one and more cups of coffee per day, compared with non-coffee drinkers, was 0.50 (95% confidence interval 0.31–0.79), and the ratio for drinkers of less than one cup per day was 0.83 (95% confidence interval 0.54–1.25). Our data confirmed an inverse association between coffee consumption and HCC mortality.

Prospective study of screening for stomach cancer in Japan

Although screening for stomach cancer is a widespread community service in Japan, the benefits of the screening program remain unclear. Our study investigated prospectively the relation between participation in stomach‐cancer screening during the past 12 months and subsequent deaths. Data was derived from the Japan Collaborative Cohort Study, in which 480 stomach‐cancer deaths were identified during an 8‐year follow‐up period. Cox proportional hazard regression was used to estimate the relative risk of death from stomach cancer and that from other causes while adjusting for potential confounding factors. In men, screening participation was associated significantly with a reduced risk of death from stomach cancer (relative risk [RR] = 0.54; 95% confidence interval [CI] = 0.41–0.70). The extent of the risk reduction was greater than potential health selection (for deaths other than stomach, RR = 0.71). The adjustment for potential confounding variables, however, attenuated the difference in risk of death (stomach cancer, RR = 0.65; other causes, RR = 0.71). In women, the magnitude of the association between screening participation and death from stomach cancer (RR = 0.74; 95% CI = 0.52–1.07) was equal to that for deaths from non‐stomach cancers (RR = 0.74). Subgroup analysis showed that women with a parental history of stomach cancer had a reduced risk of death from stomach cancer associated with screening (RR = 0.32; 95% CI = 0.12–0.87). The present results underline the potential for selection bias in observational studies, and thus it remains an open question whether screening for stomach cancer is effective.

A prospective study of stomach cancer death in relation to green tea consumption in Japan

To evaluate whether green tea consumption provides protection against stomach cancer death, relative risks were calculated using Cox proportional hazards regression analysis in the Japan Collaborative Study for Evaluation of Cancer Risk, sponsored by the Ministry of Health and Welfare (JACC Study). The study was based on 30 370 men and 42 481 women aged 40–79. After adjustment for age, smoking status, history of peptic ulcer, family history of stomach cancer along with certain dietary items, the risks associated with drinking one or two, three or four, five to nine, and 10 or more cups of green tea per day, relative to those of drinking less than one cup per day, were 1.6 (95% CI: 0.9–2.9), 1.1 (95% CI: 0.6–1.9), 1.0 (95% CI: 0.5–2.0), and 1.0 (95% CI: 0.5–2.0), respectively, in men (P for trend=0.669), and 1.1 (95% CI: 0.5–2.5), 1.0 (95% CI: 0.5–2.5), 0.8 (95% CI: 0.4–1.6), and 0.8 (95% CI: 0.3–2.1), respectively, in women (P for trend=0.488). We found no inverse association between green tea consumption and the risk of stomach cancer death.

Prospective study of diabetes mellitus and liver cancer in Japan

Previous studies have identified the association between diabetes mellitus and liver cancer. However, the detail of this association is still unclear, in terms of confounding factors, the trend according to the duration of diabetes, and the interaction between diseases associated with the liver cancer and this association. The purpose of the present study was to examine the association between diabetes and liver cancer in view of the trend and the interaction.

Yusho, a poisoning caused by rice oil contaminated with polychlorinated biphenyls.

SPORADIC outbreaks of a peculiar skin disease were reported in Fukuoka-Ken (Fukuoka Prefeeture), Japan, in early October 1968. It was charaeterized by sueh symptoms as follicular accentuation, acneform eruption, pigmentation of the skin and nails, and hypersecretion of the Meibomian gland. Staff members of the department of dermatology of the Faculty of Medicine, Kyushu University, Fukuoka, who examined some of the early patients suspected they had chloraene. A possible causal relationship between the disease and ingestion of a certain brand of rice oil was also suspected in view of the distinet familial aggregation of the patients and their common use of the oil (1). This relationship was subsequently proved, and the disease was called Yusho, or rice oil disease. To elarify the cause of the epidemic, a study group headed by Prof. S. Katsuki of the Kyushu University Faculty of Medicine was organized by the staff of that university, the School of Medicine of Kurume University, and local health departments. An epidemiologic study subgroup was set up within the study group on October 19, 1968, which was directed by Kuratsune and also included the other three authors. This subgroup immnediately designed and carried out a series of extensive surveys in close cooperation with the department of hygiene of our faculty of medicine and the departments of public health of the Prefecture of Fukuoka and of the cities of Kitakyushu, Fukuoka, and Ohmuta. The epidemic spread not only over FukuokaKen but also over 20 other prefectures in the western part of Japan. It produced 1,001 patients -502 males and 499 females-according to the latest tabulation by the section of food hygiene, Ministry of Welfare. Although our study of the epidemic was confined to Fukuoka-Ken, and the epidemic proved to be caused by accidentally contaminated oil, we believe that publication of our results will help prevent similar food poisonings. These incidents can occur anywhere in the world if sufficient care is not exercised.

Risk factors for methicillin-resistant Staphylococcus aureus (MRSA) infection in a Japanese geriatric hospital.

A case control study on MRSA infection was carried out, with the purpose of evaluating the effect of age, gender, hypoalbuminemia, the limitation of activities of daily living (ADL), the administration of antibiotics and the use of the new cephems which include third generation cephalosporins and monobactam and carbapenems, on the occurrence of MRSA infection among the inpatients in a geriatric hospital. From April 1991 to March 1994, 285 patients underwent a bacterial culture in the various clinical aspects. 118 patients were positive for MRSA, who were then used as cases while 167 patients who were negative for MRSA were used as controls. The level of serum albumin and the ADL score were lower in the MRSA group than in the non-MRSA group (P < 0.01) while the number of antibiotics administered before bacterial culture was greater in the MRSA group than in the non-MRSA group (P < 0.01). The third generation cephems were more commonly used in the MRSA positive patients than the negative patients (P < 0.01). Even after controlling for the other factors, hypoalbuminemia (OR = 1.73, 95% CI = 1.27-2.36), the limited ADL (partially limited vs without limitation: OR = 1.88, 95% CI = 1.19-2.96, completely limited vs without limitation: OR = 2.50, 95% CI = 1.64-3.82), the use of antibiotics other than the third generation cephems (vs without antibiotics: OR = 1.73, 95% CI = 1.20-2.50) and the administration of the third generation cephems (vs without antibiotics: OR = 3.12, 95% CI = 2.16-4.50) increased the risk of MRSA infection.

Consumption of toxic rice oil by ‘yusho’ patients and its relation to the clinical response and latent period

Abstract The amounts of toxic rice oil consumed individually by 141 patients with Yusho were estimated, taking into consideration their age and sex and the frequency of meals eaten at home. Since the total amount of oil consumed, the amount of oil consumed per kg per day, the amount of oil consumed during the latent period and the length of the latent period each showed a positively skew distribution, geometric means were calculated for all of them. The amounts of polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs) and polychlorinated quaterphenyls (PCQs) taken by the patients were, on average, 633, 3·4 and 596 mg, respectively, in total or 157, 0·9 and 148 hg/kg/day. The mean latent period was estimated to be 71 days, and the amounts of PCBs, PCDFs, and PCQs taken during the latent period were calculated to be, on average, 466, 2·5 and 439 mg, respectively, the smallest amounts taken by a patient during the latent period being estimated to be 111, 0·6 and 105 mg, and the smallest doses 29, 0·16 and 27 μg/kg/day, respectively. The clinical severity of the response showed a close positive correlation with the total amount of oil consumed but not with the amount of oil consumed per kg per day. The latent period and the amount of oil consumed per kg per day showed a highly significant negative correlation.