Vitamin A, retinol, and carotenoids and the risk of gastric cancer: a prospective cohort study

BACKGROUND: Vitamin A may influence gastric carcinogenesis through its essential role in controlling cell proliferation and differentiation. However, epidemiologic studies of vitamin A, retinol (preformed vitamin A), and provitamin A carotenoids in relation to the risk of gastric cancer have documented inconsistent results. OBJECTIVE: The objective of the study was to examine the associations between intakes of vitamin A, retinol, and specific carotenoids and the risk of gastric cancer in a prospective population-based cohort study of Swedish adults. DESIGN: The study cohort consisted of 82 002 Swedish adults aged 45-83 y who had completed a food-frequency questionnaire in 1997. The participants were followed through June 2005. RESULTS: During a mean 7.2-y follow-up, 139 incident cases of gastric cancer were diagnosed. High intakes of vitamin A and retinol from foods only (dietary intake) and from foods and supplements combined (total intake) and of dietary alpha-carotene and beta-carotene were associated with a lower risk of gastric cancer. The multivariate relative risks for the highest versus lowest quartiles of intake were 0.53 (95% CI: 0.32, 0.89; P for trend = 0.02) for total vitamin A, 0.56 (95% CI: 0.33, 0.95; P for trend = 0.05) for total retinol, 0.50 (95% CI: 0.30, 0.83; P for trend = 0.03) for alpha-carotene, and 0.55 (95% CI: 0.32, 0.94; P for trend = 0.07) for beta-carotene. No significant associations were found for beta-cryptoxanthin, lutein and zeaxanthin, or lycopene intake. CONCLUSION: High intakes of vitamin A, retinol, and provitamin A carotenoids may reduce the risk of gastric cancer.     

A prospective study linked both alcohol and tobacco to Dupuytren's disease

OBJECTIVE: To address the role of alcohol intake and tobacco smoking and the combination of the two on subsequent risk of Dupuytren's disease. STUDY DESIGN AND SETTING: Cohort study of 7,254 subjects enrolled in the Copenhagen City Heart Study (1981-1983). Both self-reported information on lifestyle and objective measures at the baseline examination were linked to presence of Dupuytren's disease at a subsequent examination (1991-1994) using multivariate logistic regression analysis. RESULTS: A total of 772 subjects had signs of Dupuytren's disease at follow-up. After adjustment for age, sex, educational level, diabetes, and either alcohol or tobacco consumption, respectively, odds ratios for having the disease increased in a dose-dependent manner with increasing levels of alcohol or tobacco intake; however, there was no statistical interaction between heavy smoking and heavy drinking. CONCLUSION: Alcohol intake and tobacco smoking are independently associated with increased risk of Dupuytren's disease, and the combination of the two conveys a very large risk.     

A case-control study of the relationships among silica exposure, gastric cancer, and esophageal cancer

BACKGROUND: We examined the effect of silica exposure on gastric and esophageal cancer mortality using a cancer control series in a population setting. METHODS: Cases and controls were restricted to male subjects and were drawn from death certificates in the Tobi area of Japan. A control group was selected from a series of deaths due to colon cancer, and cancers of other organs. The Japanese death certificate system is comprehensive because all deaths must be reported to the local office and death certificates are written by medical doctors. Age and smoking habits adjusted the Mantel-Haenszel odds ratios were estimated. RESULTS: For gastric cancer, the age-, smoking-adjusted odds ratios were 1.22 (95% CI 0.74-2.01) for colon cancer and the other cancer control for silica exposure work, and 1. 36 (95% CI 0.76-2.43) for silicosis. For esophageal cancer, the age- and smoking-adjusted odds ratios were 1.53 (95% CI 0.59-3.96) for the cancer control for silica exposure, and 2.33 (95% CI 0.87-6.23) for silicosis, respectively. CONCLUSIONS: The results suggest that gastric and esophageal cancer were related to silica exposure and silicosis in the study area, although they did not reach a statistically significant level because of the small sample size. The estimated odds ratios were higher for esophageal cancer and silicotic patients.     

Exposure to alcohol and tobacco and the risk of laryngeal cancer

The association between various risk factors and laryngeal cancer was evaluated using a case-control design. Subjects were chosen from the Missouri Cancer Registry from 1984 and 1985. The analysis was limited to white males and included 63 cases and 200 controls. The odds ratios (ORs) associated with previous tobacco use, adjusted for age and alcohol use, followed an increasing linear trend (p less than .01). Similarly, a dose-response relationship between alcohol use and laryngeal cancer (p less than .05) was identified. The risk for laryngeal cancer was increased synergistically by alcohol and tobacco. After controlling for alcohol and tobacco, the only occupational category with an elevated risk was nonconstruction laborers (OR = 3.82; 95% confidence interval = 1.87-5.77). Further studies of the interaction between alcohol and tobacco, occupational factors, and laryngeal cancer etiology are suggested.     

Learning the relationship between smoking,drinking alcohol and the risk of esophageal cancer

This study examined the effect of outcome feedback on learning the multiplicative relationship between daily intakes of tobacco and alcohol, and the risk of esophageal cancer. In the first of two experiments, 65 French adults judged the risk of esophageal cancer associated with combinations of five levels of intake of tobacco and five of wine. They made these judgments both before and after learning sessions in which they were shown the actual risk for each vignette. In the second experiment, 35 French adults underwent the same testing and learning, and were re-tested twice 1 month later. The study hypotheses were supported. First, prior to the learning sessions, the participants used a subadditive rule to combine the perceived risk of esophageal cancer from smoking and drinking. Second, they learned after only one training session to change to the multiplicative rule that is consistent with epidemiological data. Third, this learning persisted for 1 month. This methodology may prove useful in correcting people's underestimation of their health risks.     

A prospective study of alcohol consumption and the risk of age-related macular degeneration

PURPOSE: Vascular risk factors, including alcohol intake, have been hypothesized to play a role in the development of age-related macular degeneration (AMD). We examined the relationship of alcohol intake with AMD in the Physicians' Health Study (PHS). METHODS: The PHS was a randomized trial of aspirin and beta-carotene among 22,071 U.S. male physicians age 40 to 84 years at entry. A total of 21,041 physicians with complete data on alcohol consumption and no AMD at baseline were included in this analysis. Proportional hazards models were used to estimate relative risks (RR) and 95% confidence interval (CI). RESULTS: During an average follow-up period of 12.5 years, 278 physicians were confirmed by medical record review to have incident AMD resulting in vision loss ( acuity 20/30 or worse). After adjusting for age, randomized treatment assignment, and other potential risk factors, the RR for > or = 1 drink/week versus < 1 drink/week was 0.97 (CI: 0.78-1.21). For categories of alcohol intake, the RRs for those reporting alcohol consumption of < 1 drink/week, 1 drink/week, 2-4 drinks/week, 5-6 drinks/week, and > or = 1 drink/day were 1.00 (referent), 1.00 (0.65-1.55), 0.68 (0.44-1.04), 1.32 (0.89-1.95), and 1.27 (0.93-1.73), respectively. CONCLUSIONS: These prospective data indicate that alcohol intake is not appreciably associated with the risk of incident AMD. However, the width of the confidence intervals are compatible with a possible small effect (reduction or increase) in risk for low to moderate levels of alcohol intake, which warrant further investigation.     

A prospective study of fruits, vegetables, and risk of endometrial cancer

Case-control studies support a lower risk of endometrial cancer associated with greater vegetable consumption but not fruit consumption. One prospective study suggested an inverse association with fruits and vegetables combined. The authors examined associations for vegetables and fruits separately among women in the American Cancer Society's Cancer Prevention Study II Nutrition Cohort. After exclusions, 41,400 postmenopausal women completed a questionnaire on diet, lifestyle, and medical history at baseline in 1992-1993. Information on diet was updated in 1999; historical dietary information from 1982 was also available. The authors identified 435 eligible cases of endometrial cancer through 2003. In multivariate models, neither fruit consumption (top quintile vs. bottom: rate ratio (RR) = 1.24, 95% confidence interval (CI): 0.90, 1.70; p-trend = 0.30) nor vegetable consumption (RR = 1.21, 95% CI: 0.89, 1.65; p-trend = 0.24) at baseline was associated with risk. Results were similar when diet was cumulatively updated. Only among women who had never used hormone replacement therapy was the risk of endometrial cancer lower in the highest (vs. lowest) tertile of fruit (RR = 0.75, 95% CI: 0.52, 1.07; p-interaction = 0.03, p-trend = 0.11) or vegetable (RR = 0.80, 95% CI: 0.57, 1.13; p-interaction = 0.01, p-trend = 0.29) consumption. This prospective study does not support an association between vegetable or fruit consumption and endometrial cancer.     

A prospective study of occupation and prostate cancer risk

A wide variety of occupations has been associated with prostate cancer in previous retrospective studies. Most attention has been paid to farming, metal working, and the rubber industry. Today, these results cannot be affirmed with confidence, because many associations could be influenced by recall bias, have been inconsistent, or have not been confirmed satisfactory in subsequent studies. This study was conducted to investigate and confirm these important associations in a large prospective cohort study. The authors conducted a prospective cohort study among 58,279 men. In September 1986, the cohort members (55-69 years) completed a self-administered questionnaire on potential cancer risk factors, including job history. Related job codes were clustered in professional groups. These predefined clusters were investigated in 3 time windows: 1) profession ever performed, 2) longest profession ever held, and 3) last profession held at baseline. Follow up for incident prostate cancer was established by linkage to cancer registries until December 1993. A case-cohort approach was used based on 830 cases and 1525 subcohort members. To minimize false-positive results, 99% confidence intervals (99% CI) were calculated. Although moderately decreased prostate cancer risks were found for electricians, farmers, firefighters, woodworkers, textile workers, butchers, salesmen, teachers, and clerical workers, none of the relative risks (RR) were found to be statistically significant. For road transporters, metal workers, and managers, no association with prostate cancer risk was found. Although the RR for railway workers, mechanics, welders, chemists, painters, and cooks was moderately increased, these estimates were not statistically significant. For men who reported to have ever worked in the rubber industry, we found a substantially increased prostate cancer risk, but not statistically significant (RR, 4.18; 99% CI = 0.22-80.45). For policemen, we found a substantial and marginally statistically significant increased prostate cancer risk, especially for those who reported working as a policeman for most of their occupational life (RR, 3.91; 99% CI = 1.14-13.42) or as the last profession held at baseline (RR, 4.00; 99% CI = 1.19-13.37). Most of the previously investigated associations between occupation and prostate cancer risk could not be confirmed with confidence in this prospective study. The lack of statistical significance for rubber workers could be caused by the scarcity of rubber workers in this cohort and subsequent lack of power. The results for policemen were substantial and statistically significant, although a conservative value for significance level was used.     

Dietary folate intake, alcohol, and risk of breast cancer in a prospective study of postmenopausal women.

Low B-vitamin intake may increase risk of breast cancer through decreased DNA repair capacity. Alcohol intake increases risk for breast cancer, with evidence from prospective studies of an interaction between alcohol and folate. We explored dietary intake of folate and other B vitamins with risk of breast cancer in a cohort study of 34,387 postmenopausal women. To measure diet, we mailed a food frequency questionnaire; we estimated nutrient intakes and categorized them into four levels: <10th, 11th-30th, 31st-50th, and >50th percentiles. Through 12 years of follow-up, we identified 1,586 cases of breast cancer in the cohort at risk. We estimated relative risks (RRs) and 95% confidence intervals (CIs) through Cox regression models adjusted for age, energy, and other risk factors. Women in the lowest 10th percentile of folate intake from diet alone were at modestly increased risk of breast cancer relative to those above the 50th percentile: RR = 1.21 (95% CI = 0.91--1.61). We examined the joint association of folate intake and alcohol use on risk of breast cancer, with the reference group defined as women with high folate (>50th percentile) and no alcohol use. The RRs of breast cancer associated with low dietary folate intake were 1.08 (95% CI = 0.78--1.49) among nondrinkers, 1.33 (95% CI = 0.86--2.05) among drinkers of < or = 4 gm per day, and 1.59 (95% CI = 1.05--2.41) among drinkers of > 4 gm per day. These results suggest that the risks of postmenopausal breast cancer may be increased among women with low intakes of folate if they consume alcohol-containing beverages.     

A prospective study of moderate alcohol drinking and risk of diabetes in women

Several investigators have observed an association between alcohol consumption and elevated glucose levels, raising the possibility that alcohol may increase the risk of diabetes. This hypothesis was evaluated prospectively among 85,051 women participating in the Nurses' Health Study who were 34 to 59 years of age in 1980 and had no history of cancer, coronary heart disease, or diabetes. At baseline, participants completed an independently validated dietary questionnaire which included information on the consumption of beer, wine, and liquor. Incident cases of non-insulin-dependent diabetes were reported on follow-up questionnaires sent in 1982 and 1984 (98% response to at least one follow-up); 526 cases were confirmed by a supplementary questionnaire regarding symptoms, laboratory values, and treatment. The risk of diabetes decreased monotonically with increasing alcohol consumption (chi trend = -9.4, p less than 0.0001). Compared with nondrinkers, women consuming 5-14.9 g of alcohol per day (about 4-10 drinks per week) had an age-adjusted relative risk of diabetes of 0.4 (95% confidence interval (CI) 0.3-0.6); for 15 g or more per day, the relative risk was 0.3 (95% CI 0.2-0.4). However, a strong inverse association between alcohol drinking and body weight explained much of the apparent protective effect of alcohol. After simultaneous adjustment for Quetelet index (weight (kg)/height (m)2), family history of diabetes, total caloric intake, and age, the relative risk of diabetes for consumers of 5-14.9 g per day was 0.8 (95% CI 0.6-1.2), and for women who drank 15+ g per day, the relative risk was 0.6 (95% CI 0.3-0.9). These data provide no support for the hypothesis that moderate alcohol intake increases the risk of non-insulin-dependent diabetes.     

A prospective study of gastric and duodenal ulcer and its relation to smoking, alcohol, and diet.

The effects of environmental exposures on the development of gastric and duodenal ulcers were investigated in a prospective study of 7,624 American men of Japanese ancestry in Hawaii. After 149,291 person-years of observation, there were 280 incident cases of gastric ulcer and 149 incident cases of duodenal ulcer. The risk of both gastric and duodenal ulcers progressively increased with increasing pack-years of cigarette smoking. In contrast, alcohol intake was not associated with either type of ulcer. The risk of gastric ulcer was positively associated with the use of table salt/soy sauce, but there was no association with the consumption of other oriental foods. The risk of duodenal ulcer was inversely associated with western style diet around 1940 and with bread intake of two or more servings per day. The authors did not find any protective or adverse effect of milk and fruit consumption on peptic ulcer risk.     

Smoking, alcohol drinking, green tea consumption and the risk of esophageal cancer in Japanese men

BACKGROUND: Although smoking and alcohol drinking are established risk factors of esophageal cancer, their public health impact is unclear. Furthermore, the effect of green tea is controversial. METHODS: The present study was based on a pooled analysis of two prospective cohort studies. A self-administered questionnaire about health habits was distributed to 9,008 men in Cohort 1 and 17,715 men in Cohort 2, aged 40 years or older, with no previous history of cancer. We identified 38 and 40 patient cases with esophageal cancer among the subjects in Cohort 1 (9.0 years of follow-up) and Cohort 2 (7.6 years of follow-up), respectively. Cox proportional hazards regression was used to estimate hazard ratios (HRs) of the risk of esophageal cancer incidence. RESULTS: Cigarette smoking, alcohol drinking and green tea consumption were significantly associated with an increased risk of esophageal cancer. Compared with men who had never smoked, never drunk alcohol or green tea, the pooled multivariate HRs (95% confidence intervals) were 5.09 (1.80-14.40) (p for trend <0.0001), 2.73 (1.55-4.81) (p for trend=0.0002), or 1.67 (0.89-3.16) (P for trend=0.04) for men who were currently smoking > or =20 cigarettes/day, drinking alcohol daily, or drinking > or =5 cups green tea/day, respectively. The population attributable fractions of esophageal cancer incidence that was attributable to smoking, alcohol drinking and green tea consumption were 72.0%, 48.6%, and 22.1%, respectively. CONCLUSIONS: Among the variables studied, smoking has the largest public health impact on esophageal cancer incidence in Japanese men, followed by alcohol drinking and green tea drinking.     

基线体质指数与男性胃癌发病关系的前瞻性队列研究

目的 研究基线BMI与男性胃癌发病风险之间的关联。方法 基于开滦队列（2006-2015年）男性人群,收集身高、体重等流行病学信息。每两年随访1次,收集胃癌发病结局资料;检索开滦附属医院医疗信息系统、开滦集团保险系统、唐山市医疗保险系统,补充收集随访过程中可能遗漏的胃癌新发病例。以体重正常（18.5 kg/m² ≤ BMI<24.0 kg/m²）人群为参照组,利用Cox风险比例模型分析基线BMI与男性胃癌发病风险的关联,计算发病风险比（HR）及其95% CI。结果 共纳入109 600名男性,共随访860 399.79人年,中位随访时间8.8年,收集胃癌新发病例272例。和正常体重人群相比,调整年龄、文化程度、吸烟状态、饮酒频率、粉尘暴露、食盐习惯、饮茶习惯等潜在的混杂因素后,体重过轻人群（BMI<18.5 kg/m²）胃癌发病风险升高（HR=2.11,95% CI：1.23~3.62）,超重/肥胖与胃癌发病风险无统计学关联。按照年龄、文化程度、吸烟、饮酒、饮茶、粉尘暴露等进行分层分析,结果显示,高年龄组、高文化程度、不吸烟、不饮酒、不饮茶、有粉尘暴露人群中,低体重与胃癌发病关联依然有统计学意义。结论 体重过轻可能增加男性胃癌发病风险,且该关联受年龄、文化程度、吸烟、饮酒、饮茶、粉尘暴露等因素影响。     

广东食管癌高低发区烟酒消费与食管癌的关系

目的研究南方食管癌高发区及低发区人群烟酒消费与食管癌的关系。方法在广东高发区南澳县、低发区汕尾市采用整群抽样方法调查608名居民的吸烟、饮酒习惯。采用构筑式logistic回归及协方差分析法研究烟酒消费与食管癌的联系。结果南澳男性居民吸烟率比汕尾高13.3%,但女性吸烟率两地相同。消除年龄影响后,南澳男性居民人均累计吸烟量比汕尾多4 582包;男性人均累计吸烟量每增加1 000包,发生高食管癌死亡率的估计危险性增加1.196倍。结论吸烟量可能在南澳男性居民食管癌病因学中起着一定作用。     

Sociodemographic status, stress, and risk of prostate cancer. A prospective cohort study

PURPOSE: The social gradient in prostate cancer incidence observed in several studies may be a result of differential access to prostate cancer screening. We aim to assess if socioeconomic status, stress, and marital status are associated with prostate cancer risk in a population with free access to health care. METHODS: The 5,496 men who participated in the Copenhagen City Heart Study were asked about their income, educational level, stress level, and marital status during 1981-1983. These men were prospectively followed up in the Danish Cancer Registry until the end of 2002 and fewer than 0.1 % were lost to follow-up. RESULTS: During follow-up, 157 men were diagnosed with prostate cancer. Neither high income (HR = 1.17, 95% confidence interval [CI]: 0.78-1.76) nor high education (HR = 1.22; 95% CI: 0.76-1.96) were associated with risk of prostate cancer. There were also no differences in prostate cancer risk according to stress (HR = 0.99; 95% CI: 0.90-1.09) or marital status. CONCLUSION: In a racially homogeneous population of Caucasians with free access to health care, we found no evidence of a relation between sociodemographic variables or stress and subsequent risk of prostate cancer.     

Alcohol drinking and tobacco smoking in gastric cancer. A case-control study

This study compares 210 cases of cancer of the stomach (138 males and 72 females) with 630 controls (414 males and 216 females) afflicted with a wide variety of diseases. All patients (cases and controls) were admitted for treatment at the University Hospital of Montevideo, Uruguay in the time period July 1985-December 1988. They were submitted to the same detailed questionnaire by 3 social workers unaware of the objectives of the study. The analysis was performed at the Louisiana State University of New Orleans, using multiple logistic regression. The variables analyzed were cigarette smoking, alcohol ingestion, salted meat intake, total vegetable consumption, total fruit consumption and "mate" ingestion. Strong positive associations were found in both sexes for low fruit and vegetable consumption, high intake of salted meat and "mate" ingestion. Only males showed significantly elevated OR's for tobacco smoking and alcohol drinking. Of the main tobacco variables, time-dependent one's (age at start, duration) displayed significant gradients of increasing risks. Thus, a prolonged exposure seems more important than the amount smoked per day for the risk of developing gastric carcinoma. Both wine and hard liquor carried increased OR's, but heavy drinkers of wine displayed a six-fold increase in risk, replicating previous reports from France.     

A prospective study of job strain and risk of breast cancer

BACKGROUND: There is conflicting evidence on whether stress is a risk factor for breast cancer. The present study examined prospectively the relationship between stress at work and risk of breast cancer. METHODS: Participants comprised 26 936 postmenopausal women in the Nurses' Health Study ages 46-72 who were in paid employment, and who had no previous history of cancer. Multivariate-adjusted regression analysis was used to examine the relationship between job strain (measured by the Karasek Job Content Questionnaire in 1992) and risk of incident invasive and in situ breast cancer. RESULTS: From 1992 through 1994, 219 women were diagnosed with breast cancer. No evidence was found for a relationship between job stress and risk of breast cancer. Compared with women in low strain jobs, the multivariate-adjusted relative risks of breast cancer were RR = 0.78 (95% CI : 0.52-1.16) for high-strain jobs; RR = 0.76 (95% CI : 0.49-1.17) for active jobs; and RR = 0.94 (95% CI : 0.67-1.34) for passive jobs. Although job strain was related to less breast cancer screening among women in highly demanding jobs, it was not associated with tumour size. CONCLUSIONS: Job stress was not related to an increase in the incidence of breast cancer in the present cohort of nurses.