膀胱癌与糖精

大鼠食入大量的糖精发生膀胱癌的实验引起了人们对糖精与膀胱癌关系的兴趣。这些研究结果的意义及其与人的关系尚不明确。有几组研究人员已找到了可能因食用糖精引起人的膀胱癌发病率增高的证据。据调查,英、美两国膀胱癌死亡率并未因食用糖精而见增高,而且糖尿病患者表明,即使他们的糖精摄入量超过正常,但膀胱癌死亡率也未增高。Morgan和Jain采用信件询问的方式,直接调查了364名膀胱癌患者(男性240人)和470名对照患者(良性前列腺肥大310人及尿失禁的女性)。尽管回信率低(癌患者     

膀胱癌危险因素交叉配比病例对照研究

对１１２例膀胱癌病例进行与非肿瘤对照和胃癌对照交叉配比病例对照研究，结果相对于胃癌、膀胱癌的特异危险因素为危险职业作业史（ＯＲ＝２．０７）、泌尿道病史（ＯＲ＝２．８３）、憋尿（ＯＲ＝２．８７）、常服解热镇痛药（ＯＲ＝２．６７）；较特异危险因素为吸烟（ＯＲ＝２．７５）和食用糖精（≥１５次／年，ＯＲ＝４．００）；一般因素为精神创伤（ＯＲ＝２．１１）。遗传易感性似乎不明显。     

膀胱癌危险因素病例对照研究

对１１２例膀胱癌住院病例进行了１∶１病例对照研究。单因素分析表明：吸烟、危险职业和作业史、泌尿道病史、憋尿、常服解热镇痛药、年用糖精次数、８０年代蔬菜水果指数、每月饮酒次数、饮茶、急暴躁情绪、精神创伤史等与膀胱癌显著相关。多元条件Ｌｏｇｉｓｔｉｃ回归分析表明。膀胱癌的主要危险因素为吸烟、使用糖精、精神创伤、泌尿道病史、危险职业和作业史，考虑多重共线的作用，憋尿和常服解热镇痛药也为主要危险因素。饮茶、饮酒可能为吸烟的伴随因素。许多因素间存在明显协同作用。     

美国国立卫生研究所的糖精研究结果

1977年卡特总统批准了食品与药物管理局(FDA)对糖精禁用的法令,此后对糖精致膀胱癌问题提出了疑问。因而由国家科学院(NAS)和国立癌症研究所(NCI)对糖精的致癌问题作进一步的调查研究。NAS负责审查已有关于糖精致膀胱癌的动物实验的资料;NCI 则组织进行大规模的流行病学调查,以观察膀胱癌患者是否都是糖精使用者。NAS 在1978年报告了其审查结果:糖精为一弱致癌物并可促进某些化学物质的致癌作用。现 NCI 提     

关于糖精的争议

1977年3月9日美国食品和药物管理局(FDA)建议禁止销售美国市场上仅有的人工甜味剂——糖精(saccharin)。这个决定主要根据加拿大的大鼠实验,该实验用糖精喂饲100只大鼠(雌雄各半),剂量为饲料的5%(约2,500mg/kg体重,相当干一个人每天饮800瓶12盎司瓶装汽水),有3只发生膀胱癌,而其子代(在子宫内即接触糖精,出生后又喂饲糖精),14%发生膀胱肿瘤(见下表)。     

对于糖精与癌症的不同观点

1977年11月美国食品药物管理局(FDA)提出禁用糖精18个月,总统签了字。这一禁令的目的在于收集更多的糖精与膀胱癌相关的资料。现正在进行两项主要的研究:一项是由国家科学院进行,复习有关文献,分析糖精的害处与益处,并观察由于控制糖精对     

饮水氯消毒暴露与膀胱癌联系的病例对照研究

目的 评价重庆地区饮水氯消毒长期暴露与膀胱癌发生的联系。方法 采用成组病例对照研究，设计调查表，收集1998年12月至2000年10月的住院膀胱癌患（211人）为病例组，同期住院非泌尿系统疾病病人（230人），为对照组，两组年龄、性别及本地居住时间无显性差异；采用EPI501和SPSS软件包进行数据资料管理和单因素、多因素非条件Logistic回归分析。结果 长期饮用氯消毒水、每天饮水量以及其他途径接触（如洗有／碗、洗澡／淋浴）饮氯消毒水均与膀胱癌发生有一定联系，危险性随饮用氯消毒水年限增加而增大。结论 重庆地区饮水消毒暴露可能是膀胱癌发生的危险因素，应当重视该领域的流行病学研究。     

关于糖精布告的解释

1973年12月27日,日本卫生部第341号布告对一部分食品和附加剂的规格标准进行修改。对糖精的修改是基于12月18日食品卫生调查会的附加剂和毒性联合部会,对糖精的安全性做了慎重审议而修改的。该联合部会的结论为: (1)认为糖精对第一代的实验动物无致癌性。(2)在美国观察两代动物的两个实验结果,认为虽然高浓度组在二代发生了膀胱癌,但是否为实验用糖精中所含的不纯物所致?对此持疑问态度。     

环境卫生与监测

32 34 3　饮水氯消毒暴露与膀胱癌联系的病例对照研究 /林　辉…∥中国公共卫生 2 0 0 2 ,18( 4) 397～ 399评价重庆地区饮水氯消毒长期暴露与膀胱癌发生的联系。采用成组病例对照研究 ,设计调查表 ,收集19 98年 12月至 2 0 0 0年 10月的住院膀胱癌患者 ( 2 11人 )为病例组 ,同期住院非泌尿系统疾病病人 ( 2 30人 )为对照组 ,两组年龄、性别及本地居住时间无显著性差异 ;采用EPI 5 0 1和SPSS软件包进行数据资料管理和单因素、多因素非条件Logistic回归分析。结果 ,长期饮用氯消毒水、每天饮水量以及其他途径接触 (如洗衣/碗、洗澡 /…     

用糖精代替蔗糖 赚黑心钱骗你没商量

糖精也叫糖精钠,来源于甲苯、氯磺酸、领甲苯胺等石化产品,或是干脆从煤焦油中提炼出来的有机化工合成物。 专家告诫,短时间内食用大量糖精,会引起血小板减少而造成急性大出血,引发恶性事件。一位49岁的中年男子,平时对甜味食品就有特殊偏好,接触了糖精后,觉得既便宜又好吃,遂用西红柿蘸糖精水作为美味小吃,     

Bladder cancer mortality in England and Wales in relation to cigarette smoking and saccharin consumption

Cohort analyses of bladder cancer mortality rates in men and women in England and Wales have been compared with figures for the per caput consumption of saccharin and cigarette tobacco and with similar analyses of cigarette smoking habits. The increase in bladder cancer mortality rates in male cohorts born since 1870 can be attributed to cigarette smoking, and there is no evidence of any break in the continuity of the trends in either men or women which corresponds to the introduction of saccharin.     

Attributable risks for bladder cancer in Northern Italy

Attributable risks (ARs) for bladder cancer were computed in relationship to cigarette smoking, coffee consumption, low intake of vegetables, history of cystitis, and occupation using data from a case-control study conducted in northern Italy between 1985 and 1993. Cases were 431 patients with histologically confirmed bladder cancer, and controls were 491 patients admitted to the same network of hospitals for acute, nonneoplastic, and non-urinary-tract diseases. Overall, the AR estimates were 49% for cigarette smoking, 23% for coffee consumption, 16% for low intake of vegetables, 12% for history of cystitis, and 4% for occupation. These five factors together explained more than 70% of bladder cancer cases in this population. The AR for cigarette smoking was significantly higher among men (56%) than women (17%), whereas coffee consumption, low vegetable intake, and cystitis were more important (but not significantly so) among women. These results suggest that more than 2500 of the 5400 deaths due to bladder cancer in Italy in 1990 could have been prevented by the elimination of cigarette smoking. With some appropriate dietary modification and intervention to prevent urinary tract infections and occupational exposures, this figure could approach 4000 avoidable deaths. Thus, bladder cancer could become a rare cause of death in this population.     

Smoking and other risk factors for bladder cancer in women

BACKGROUND: Bladder cancer is three to five times more frequent in men than in women, and hence only a few studies have focused only on females. METHODS: A case-control study was conducted between 1985 and 1992 in two areas of northern Italy, and included 110 women with histologically confirmed bladder cancer and 298 controls, admitted to the same network of hospitals of cases for acute, non-neoplastic, non-urinary or genital tract diseases. Multivariate odds ratios (ORs) were computed using unconditional multiple logistic regression. RESULTS: Compared to never smokers, current smokers (OR = 2.87) had significantly elevated risks of bladder cancer. High intake of vegetables was inversely related to the disease (OR = 0.32), while history of occupation in chemical, dyes/paints or pharmaceutical industry (OR = 3.01) was directly associated to risk of bladder cancer. The OR was 3.29 for ever use of menopause hormone replacement therapy. CONCLUSIONS: This study confirms that cigarette smoking is the prominent risk factor for bladder cancer in women as in men, with similar relations in both sexes. It also confirms that selected occupational factors are related to bladder cancer risk, and supports a favourable role of vegetables. The apparent relation with hormone replacement therapy in menopause needs interpretation and further investigation.     

Bladder cancer and black tobacco cigarette smoking

A retrospective study was planned in the Hérault (Mediterranean) region of France where bladder cancer mortality and incidence rates are high. In the present paper, variations in bladder cancer risk according to various smoking-related variables, in particular time of exposure and type of tobacco, are examined. This case-control study with 219 male incident cases and 794 male population controls randomized from electoral rolls was carried out in 1987–89. Trained interviewers obtained information on demographics, dietary habits (coffee, alcohol, artificial sweeteners, vegetables, spices, etc.), occupational exposures and detailed history of tobacco smoking (average number of cigarettes per day, number of years of smoking, age at which they began and/or quitted smoking, use of filter-tip and type of tobacco). The odds ratio (OR) for cigarette smokers versus non-smokers was greater than 5. Results for number of cigarettes daily, duration of smoking and lifetime smoking showed a highly significant dose-response relationship, which was confirmed when these variables were treated as continuous in a logistic regression model. Eighty-eight percent of the smokers used black tobacco. Quitting smoking did not result in a significant reduction in bladder cancer risk. Higher risks were associated with starting to smoke at an early age (OR before age 13 versus after age 21=3.42; 95% CI 1.07–10.9) and with black tobacco smoking (OR black versus blond =1.63; 95% CI 0.73–3.64). Results suggest that black tobacco may be more harmful than blond tobacco and may have an early non-reversible role in bladder carcinogenesis.     

Cancer mortality and saccharin consumption in diabetics.

The mortality experience of 5971 members of the British Diabetic Association (BDA) was followed-up for between five and eight years to mid-1973. Overall, 1207 deaths occurred compared with 778 expected from the mortality of the population of England and Wales in 1972. This excess of deaths was due almost entirely to diabetes mellitus and ischaemic heart disease. Deaths from cancer (128) were significantly fewer than expected (168), mainly because of a deficit in the number of deaths from cancers related to smoking (cancers of the buccal cavity and pharynx, oesophagus, respiratory system, and bladder). There was also a lower than expected mortality from chronic bronchitis and emphysema. Data on saccharin consumption by BDA members showed that more than half of them used saccharin tablets daily, with an overall daily intake of three to six tablets, depending on age and sex. Information on a small sample of survivors from the mortality study suggested that about 23% of them would have taken saccharin daily for 10 years or more and 10% for 25 years or more by the end of the follow-up. It was concluded that these relatively high levels of saccharin intake had not increased the risk of cancer in general among BDA members.     

Bladder cancer mortality in diabetics in relation to saccharin consumption and smoking habits.

The frequency with which diabetes mellitus was mentioned on the death certificates of 18,733 patients dying from bladder cancer has been compared with that of 19,709 patients dying from other cancers (excluding cancer of the lung and pancreas). The estimated relative risk of bladder cancer in diabetics was 0-98 with 95% confidence limits 0-70-1-38. There was no increase in risk of bladder cancer in patients with diabetes of long duration. Diabetics were shown by questionnaire to consume substantially more saccharin than non-diabetics, and the duration of regular saccharin use by diabetics was highly correlated with the duration of diabetes. There was therefore no evidence from this study that consumption of above average amounts of saccharin had led to bladder cancer in diabetics. The proporation of current smokers among diabetics was significantly less than among non-diabetics, and this may account for a low relative risk of lung cancer in the former (0-72).     

Bladder cancer mortality in diabetics in relation to saccharin consumption and smoking habits.

The frequency with which diabetes mellitus was mentioned on the death certificates of 18,733 patients dying from bladder cancer has been compared with that of 19,709 patients dying from other cancers (excluding cancer of the lung and pancreas). The estimated relative risk of bladder cancer in diabetics was 0-98 with 95% confidence limits 0-70-1-38. There was no increase in risk of bladder cancer in patients with diabetes of long duration. Diabetics were shown by questionnaire to consume substantially more saccharin than non-diabetics, and the duration of regular saccharin use by diabetics was highly correlated with the duration of diabetes. There was therefore no evidence from this study that consumption of above average amounts of saccharin had led to bladder cancer in diabetics. The proporation of current smokers among diabetics was significantly less than among non-diabetics, and this may account for a low relative risk of lung cancer in the former (0-72).     

Diet and bladder cancer: a meta-analysis of six dietary variables

In 1996, more than 300,000 new cases of bladder cancer were diagnosed worldwide. Besides tobacco smoking, occupation, and other factors, diet may play a role in causation of this illness. The authors performed a meta-analytical review of epidemiologic studies linking six dietary factors to bladder cancer. These factors include retinol, beta-carotene, fruits, vegetables, meat, and fat. Increased risks of bladder cancer were associated with diets low in fruit intake (relative risk (RR) = 1.40, 95% confidence interval (CI): 1.08, 1.83), and slightly increased risks were associated with diets low in vegetable intake (RR = 1.16, 95% CI: 1.01, 1.34). Elevated risks were identified for diets high in fat intake (RR = 1.37, 95% CI: 1.16, 1.62) but not for diets high in meat intake (RR = 1.08, 95% CI: 0.82, 1.42). No increased risks were found for diets low in retinol (RR = 1.01, 95% CI: 0.83, 1.23) or beta-carotene (RR = 1.10, 95% CI: 0.93, 1.30) intake. These results suggest that a diet high in fruits and vegetables and low in fat intake may help prevent bladder cancer, but the individual dietary constituents that reduce the risks remain unknown.     

Modifiable risk factors for the prevention of bladder cancer: a systematic review of meta-analyses

Each year, 430,000 people are diagnosed with bladder cancer. Due to the high recurrence rate of the disease, primary prevention is paramount. Therefore, we reviewed all meta-analyses on modifiable risk factors of primary bladder cancer. PubMed, Embase and Cochrane database were systematically searched for meta-analyses on modifiable risk factors published between 1995 and 2015. When appropriate, meta-analyses (MA) were combined in meta–meta-analysis (MMA). If not, the most comprehensive MA was selected based on the number of primary studies included. Probability of causation was calculated for individual factors and a subset of lifestyle factors combined. Of 1496 articles identified, 5 were combined in MMA and 21 were most comprehensive on a single risk factor. Statistically significant associations were found for current (RR 3.14) or former (RR 1.83) cigarette smoking, pipe (RR 1.9) or cigar (RR 2.3) smoking, antioxidant supplementation (RR 1.52), obesity (RR 1.10), higher physical activity levels (RR 0.86), higher body levels of selenium (RR 0.61) and vitamin D (RR 0.75), and higher intakes of: processed meat (RR 1.22), vitamin A (RR 0.82), vitamin E (RR 0.82), folate (RR 0.84), fruit (RR 0.77), vegetables (RR 0.83), citrus fruit (RR 0.85), and cruciferous vegetables (RR 0.84). Finally, three occupations with the highest risk were tobacco workers (RR 1.72), dye workers (RR 1.58), and chimney sweeps (RR 1.53). The probability of causation for individual factors ranged from 4 to 68 %. The combined probability of causation was 81.8 %. Modification of lifestyle and occupational exposures can considerably reduce the bladder cancer burden. While smoking remains one of the key risk factors, also several diet-related and occupational factors are very relevant.     

Dietary risk factors in human bladder cancer

Retrospective data on dietary habits, employment history and tobacco use were obtained from 569 bladder cancer patients and 1025 age-matched controls admitted to Roswell Park Memorial Institute. Sex-adjusted relative risks revealed increases in risk for lower levels of an index of vitamin A intake. A similar pattern of risk elevation was associated with infrequent milk and carrot intake. Some elevation of risk was found for heavy coffee drinking but the apparent protective effect for milk consumption was not found to be a spurious result of lower coffee intake. Neither was the role of vitamin A explained by its relationship with smoking or employment in high risk occupations. Some association of bladder cancer with infrequent consumption of cruciferous vegetables was also observed. The findings of this investigation are consistent with tumor inhibition by retinoids in animal studies and the low risk associated with vitamin A in epidemiologic studies of lung cancer.