Cigarette and alcohol consumption and the risk of colorectal cancer in Shanghai, China

Changing Colorectal Cancer Trends in Asians: Epidemiology and Risk Factors

Once an infrequent disease in parts of Asia, the rate of colorectal cancer in recent decades appears to be steadily increasing. Colorectal cancer represents one of the most important causes of cancer mortality worldwide, including in many regions in Asia. Rapid changes in socioeconomic and lifestyle habits have been attributed to the notable increase in the incidence of colorectal cancers in many Asian countries. Through published data from the International Agency for Cancer Research (IARC), we utilized available continuous data to determine which Asian nations had a rise in colorectal cancer rates. We found that East and South East Asian countries had a significant rise in colorectal cancer rates. Subsequently, we summarized here the known genetics and environmental risk factors for colorectal cancer among populations in this region as well as approaches to screening and early detection that have been considered across various countries in the region.

Association between alcohol consumption and oesophageal microbiota in oesophageal squamous cell carcinoma

BACKGROUND

Microbiota has been reported to play a role in cancer patients. Nevertheless, little is known about the association between alcohol consumption and resultant changes in the diversity and composition of oesophageal microbiota in oesophageal squamous cell carcinoma (ESCC).

METHODS

We performed a hospital-based retrospective study of 120 patients with pathologically diagnosed primary ESCC. The relevant information for all study participants were collected through a detailed questionnaire. The differences in adjacent tissues between non-drinkers and drinkers were explored using 16S rRNA gene sequencing. Raw sequencing data were imported into QIIME 2 to analyse the diversity and abundance of microbiota. Linear discriminant analysis effect size (LEfSe) and unconditional logistic regression were performed to determine the bacterial taxa that were associated with drinking.

RESULTS

The Shannon diversity index and Bray-Curtis distance of oesophageal microbiota were significantly different among drinkers(P < 0.05). The alcohol-related bacteria were primarily from the orders Clostridiales, Gemellales and Pasteurellales, family Clostridiaceae, Lanchnospiraceae, Helicobacteraceae, Alcaligenaceae, Bacteroidaceae, Pasteurellaceae and Gemellaceae; genus Clostridium, Helicobacter, Catonella, Bacteroides, Bacillus, Moraxella, and Bulleidia; and species B. moorei and longum (genus Bifidobacterium). In addition, the diversity and abundance of these microbiota were observed to be affected by the age, residential districts of the patients, and sampling seasons. Moreover, the higher the frequency and years of alcohol consumption, the lower was the relative abundance of genus Catonella that was observed.

CONCLUSION

Alcohol consumption is associated with alterations in both the diversity and composition the of the oesophageal microbiota in ESCC patients.

Smoking and colorectal cancer: A pooled analysis of 10 population-based cohort studies in Japan

Smoking has been consistently associated with the risk of colorectal cancer (CRC) in Western populations; however, evidence is limited and inconsistent in Asian people. To assess the association of smoking status, smoking intensity and smoking cessation with colorectal risk in the Japanese population, we performed a pooled analysis of 10 population-based cohort studies. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox's proportional hazards model and then pooled using a random-effects model. Among 363 409 participants followed up for 2 666 004 person-years, 9232 incident CRCs were identified. In men, compared with never smokers, ever smokers showed higher risk of CRC. The HRs (95% CI) were 1.19 (1.10-1.29) for CRC, 1.19 (1.09-1.30) for colon cancer, 1.28 (1.13-1.46) for distal colon cancer and 1.21 (1.07-1.36) for rectal cancer. Smoking was associated with risk of CRC in a dose-response manner. In women, compared with never smokers, ever smokers showed increased risk of distal colon cancer (1.47 [1.19-1.82]). There was no evidence of a significant gender difference in the association of smoking and CRC risk. Our results confirm that smoking is associated with an increased risk of CRC, both overall and subsites, in Japanese men and distal colon cancer in Japanese women.

Protein functionalised self assembled monolayer based biosensor for colon cancer detection

We report results of the studies relating to the fabrication of a surface plasmon resonance (SPR) based label-free immunosensor for real-time monitoring of endothelin-1 (ET-1), a colon cancer biomarker. A gold disk modified with a self-assembled monolayer (SAM) of 11-mercaptoundecanoic acid (11-MUA) was functionalised via covalent immobilization of monoclonal anti-ET-1 antibodies using EDC-NHS (1-(3-(dimethylamine)-propyl)-3-ethylcarbodiimide hydrochloride, N-hydroxy succinimide) chemistry. This immunosensing platform (ethanolamine/anti-ET-1/11-MUA/Au) was characterized via atomic force microscopy (AFM), contact angle (CA) and Fourier transform infrared (FT-IR) spectroscopic techniques. The fabricated SPR electrode was further used to detect ET-1 in the broad concentration range 2-100 pg mL^-1, with a detection limit of 0.30 pg mL^-1 and remarkable sensitivity of 2.18 m^o pg^-1mL. The adsorption mechanism was studied using monophasic model and the values of association (k_a) and dissociation (k_d) constants for anti-ET-1 and ET-1 binding were calculated to be 4.4 ± 0.4 × 10⁵ M^-1 s^-1 and 2.04 ± 0.0003 × 10^-3 s^-1, respectively. The results obtained via analysis of serum samples of colorectal cancer patients were found to be in good agreement with those obtained from enzyme-linked immunosorbent assay (ELISA) technique. Further, electrochemical studies were performed to prove the efficacy of the fabricated platform as a point of care device for the detection of ET-1.

Dietary patterns and colorectal cancer risk: a meta-analysis

The analysis of dietary patterns has recently drawn considerable attention as a method of investigating the association between the overall whole diet and the risk of colorectal cancer. However, the results have yielded conflicting findings. Here, we carried out a meta-analysis to identify the association between dietary patterns and the risk of colorectal cancer. A total of 40 studies fulfilled the inclusion criteria and were included in this meta-analysis. The highest category of 'healthy' dietary pattern compared with the lowest category was apparently associated with a decreased risk for colorectal cancer [odds ratio (OR)=0.75; confidence interval (CI): 0.68-0.83; P<0.00001]. An increased risk of colorectal cancer was shown for the highest compared with the lowest category of a 'western-style' dietary pattern (OR=1.40; CI: 1.26-1.56; P<0.00001). There was an increased risk of colorectal cancer in the highest compared with the lowest category of 'alcohol-consumption' pattern (OR=1.44; CI: 1.13-1.82; P=0.003). The results of this meta-analysis indicate that a 'healthy' dietary pattern may decrease the risk of colorectal cancer, whereas 'western-style' and 'alcohol-consumption' patterns may increase the risk of colorectal cancer.

Smoking Status and Gastric Cancer Risk: An Updated Meta-Analysis of Case-Control Studies Published in the past Ten Years

Background

A meta-analysis of published studies was performed in order to clarify the risk of gastric cancer associated with cigarette smoking status.

Methods

Eligible studies were all the case-control studies investigating an association between smoking status and gastric cancer published from January 1, 1997, until June 30, 2006. In order to evaluate the quality of the published data, a qualitative scoring of papers was applied. The principal outcome measure was the odds ratio for the risk of gastric cancer associated with the smoking status using a random effects model. Cigarette smoking status was assessed in two ways: ever (current and ex) versus never smokers; current versus never smokers.

Results

We found a statistically significant result for the association between ever smoking status and gastric cancer risk (OR = 1.48; 95% CI, 1.28–1.71), considering 14,442 cases and 73,918 controls. Moreover, we found an odds ratio of 1.69 for current smoker status in comparison to never smokers (95% CI, 1.35–2.11). Considering only high quality studies, the odds ratio increased by 43% for gastric cancer risk in ever smokers (OR = 1.43; 95% CI, 1.24–1.66; Q = 378.60, P <0.00001; I2 = 90%) and by 57% in current smokers (OR = 1.57; 95% CI, 1.24–2.01). We also considered separately Caucasians and Asian studies, finding for ever smokers an odds ratio of 1.46 (95% CI, 1.25–1.70; Q = 125.68, P <0.00001; I2 = 82.5%) and of 1.47 (95% CI, 1.13–1.91; Q = 366.77, P <0.00001; I2 = 94%), respectively.

Conclusions

From the results of this quantitative meta-analysis, it appears that cigarette smoking has to be considered an important risk factor. The use of qualitative scoring decreases the magnitude of the relationship both for ever and current smoker exposure by 5–12%. Future studies on this topic need to clarify the biological interaction between environmental factors (such as cigarette smoking) and different polymorphisms on gastric cancer.

Association between smoking and deaths due to colorectal malignant carcinoma: a national population-based case-control study in China

BACKGROUND

This study explored the association between smoking and colorectal malignant carcinoma (CRC) in the Chinese population at the national level for the first time.

METHODS

In the China Nationwide Retrospective Mortality Survey conducted during 1989-1991, 12,942 CRC cases among 1,136,336 all-cause deaths aged ≥30 years were randomly assigned 25,884 control interviews from 325,255 surviving spouses of all-cause deaths across 103 urban and rural areas.

RESULTS

Compared with non-smokers, smoking significantly increased the risk of CRC-specific mortality by 9.8% (odds ratio (OR)=1.098, 95% confidence interval (CI)=1.046-1.153) adjusted for sex, age, and residence. There were significant dose-response relationships between smoking and CRC, such as smoking years, cigarettes smoked daily, and age at onset of smoking. Long-term heavy smokers aged ≥50 years with ≥30 smoking years and ≥20 cigarettes daily had an excess risk of CRC deaths of 30.2% (OR=1.302, 95% CI=1.214-1.397). The strongest association between these smoking variables, such as long-term heavy smokers (OR=1.604, 95% CI=1.341-1.919), and CRC was observed among rural men.

CONCLUSIONS

Quitting smoking at any time would likely be beneficial to CRC prevention. Long-term heavy smokers and rural men should be viewed as special targets for smoking prevention and cessation programs.

Risk of colorectal cancer associated with active smoking among female teachers

PURPOSE

The objective of this study was to examine the risk of colorectal cancer associated with active smoking among members of the California Teachers Study (CTS), a large cohort of female public school employees for whom highly detailed smoking information is available.

METHODS

The analysis was conducted among the 122,264 CTS participants who lived in California at cohort entry in 1995/1996, had no prior history of colorectal cancer, and provided detailed smoking information. 1,205 cases of invasive colorectal cancer prospectively diagnosed in 1995-2009 were identified from the California Cancer Registry, including 650 in the proximal colon, 267 in the distal colon, and 288 in the rectum. Hazard ratios and 95% confidence intervals were estimated using Cox proportional hazards models, stratified by age at cohort entry, and adjusted for race/ethnicity.

RESULTS

Compared to never smokers, current smokers had an approximately 30% increased risk of colorectal cancer. Overall, a slightly elevated risk was also noted for former smokers. Among former smokers, risks appeared to remain elevated for up to 20 years following cessation. Risks among former and current smokers increased with greater intensity and duration of smoking. Little evidence for heterogeneity in risk was noted for colon versus rectal cancer or for different subsites within the colon.

CONCLUSIONS

These results provide convincing evidence that heavy and/or long-term smoking is a risk factor for cancers of the colon and rectum. Such evidence should be considered when updating screening guidelines to include targeting people with long active smoking histories.

Joint Association of Dietary Pattern and Physical Activity Level with Cardiovascular Disease Risk Factors among Chinese Men: A Cross-Sectional Study

The purpose of this cross-sectional study was to investigate the joint associations of physical activity level (PAL) and dietary patterns in relation to cardiovascular disease (CVD) risk factors among Chinese men. The study population consisted of 13 511 Chinese males aged 18–59 years from the 2002 China National Nutrition and Health Survey. Based on dietary data collected by a food frequency questionnaire, four dietary patterns were identified and labeled as “Green Water” (high consumption of rice, vegetables, seafood, pork, and poultry), “Yellow Earth” (high consumption of wheat flour products and starchy tubers), “New Affluent” (high consumption of animal sourced foods and soybean products), and “Western Adopter” (high consumption of animal sourced foods, cakes, and soft drinks). From the information collected by a 1-year physical activity questionnaire, PAL was calculated and classified into 4 categories: sedentary, low active, active, and very active. As compared with their counterparts from the New Affluent pattern, participants who followed the Green Water pattern had a lower likelihood of abdominal obesity (AO; 50.2%), hypertension (HT; 37.9%), hyperglycemia (HG; 41.5%), elevated triglyceride (ETG; 14.5%), low HDL (LHDL; 39.8%), and metabolic syndrome (MS; 51.9%). When compared to sedentary participants, the odds ratio of participants with very active PAL was 0.62 for AO, 0.85 for HT, 0.71 for HG, 0.76 for ETG, 0.74 for LHDL, and 0.58 for MS. Individuals who followed both very active PAL and the Green Water pattern had a lower likelihood of CVD risk factors (AO: 65.8%, HT: 39.1%, HG: 57.4%, ETG: 35.4%, LHDL: 56.1%, and MS: 75.0%), compared to their counterparts who followed both sedentary PAL and the New Affluent pattern. In addition, adherence to both healthy dietary pattern and very active PAL presented a remarkable potential for CVD risk factor prevention.

Effects of passive smoking on breast cancer risk in pre/post-menopausal women as modified by polymorphisms of PARP1 and ESR1

OBJECTIVES

The association between passive smoking and breast cancer risk differs in pre- and post-menopausal women. We aimed to explore the modification effects of PARP1 rs1136410 and ESR1 rs2234693 on the association between passive smoking and breast cancer risk among pre- and post-menopausal women.

DESIGN AND METHODS

A case-control study of 839 breast cancer cases and 863 controls was conducted. The gene-environment interactions were tested after adjusting for potential breast cancer risk factors with unconditional logistic regression models.

RESULTS

We found that the effect of passive smoking was modified by the genotypes in both pre- and post-menopausal women, but in opposite directions. The combination of the TC/CC genotypes of ESR1 rs2234693 and passive smoking significantly increased the risk of breast cancer [OR (95%CI): 2.06 (1.39-3.05)] in pre-menopausal women. A significant association was observed between TT genotype and passive smoking [OR (95%CI): 2.40 (1.27-4.53)] in postmenopausal women. For PARP1 rs1136410, similar differential associations were observed, but the interactions were not significant.

CONCLUSIONS

These results imply that the risk of breast cancer from passive smoking may be influenced by genetic factors, and that the association may differ depending on menopausal status.

Risk of esophagus cancer in diabetes mellitus: a population-based case-control study in Taiwan

Background

Diabetes mellitus (DM) has been associated with the cancer risk. This study investigated relationship between DM and esophageal cancer using Taiwan’s insurance data.

Methods

We identified 549 patients with esophageal cancer newly diagnosed in 2000-2009 and randomly selected 2196 controls without any cancer, frequency matched by sex, age and diagnosis year of cases. Logistic regression model estimated odds ratios (ORs) and 95% confidence intervals (CI) of esophageal cancer associated with DM, sex, age. co-morbidities and medications.

Results

Cases were more prevalent than controls for alcoholism and esophageal disorders and using nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 inhibitors but not DM. Esophageal cancer had no association with DM (OR 0.99, 95% CI 0.71-1.37), but significantly associated with alcoholism (OR 14.1, 95% CI 7.87-25.4), esophageal ulcer (OR 10.1, 95% CI 5.70-17.9), esophageal reflux (OR 3.47, 95% CI 2.14-5.26) and uses of NSAIDs (OR 2.73, 95% CI 1.80-4.13). An elevated risk of esophageal cancer appeared in DM patients taking insulin (OR 2.57, 95% CI 1.08-6.15) or sulfonyurea (OR 3.80, 95% CI 1.16-12.5).

Conclusions

Patients with DM are not at higher risk for esophagus cancer. However, esophageal disorders and anti-diabetic drugs are associated with the risk of the disease.

Educational level and risk of colorectal cancer in EPIC with specific reference to tumor location

Existing evidence is inconclusive on whether socioeconomic status (SES) and educational inequalities influence colorectal cancer (CRC) risk, and whether low or high SES/educational level is associated with developing CRC. The aim of our study was to investigate the relationship between educational level and CRC. We studied data from 400,510 participants in the EPIC (European Prospective Investigation into Cancer and Nutrition) study, of whom 2,447 developed CRC (colon: 1,551, rectum: 896, mean follow-up 8.3 years). Cox proportional hazard regression analysis stratified by age, gender and center, and adjusted for potential confounders were used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI). Relative indices of inequality (RII) for education were estimated using Cox regression models. We conducted separate analyses for tumor location, gender and geographical region. Compared with participants with college/university education, participants with vocational secondary education or less had a nonsignificantly lower risk of developing CRC. When further stratified for tumor location, adjusted risk estimates for the proximal colon were statistically significant for primary education or less (HR 0.73, 95%CI 0.57-0.94) and for vocational secondary education (HR 0.76, 95%CI 0.58-0.98). The inverse association between low education and CRC risk was particularly found in women and Southern Europe. These associations were statistically significant for CRC, for colon cancer and for proximal colon cancer. In conclusion, CRC risk, especially in the proximal colon, is lower in subjects with a lower educational level compared to those with a higher educational level. This association is most pronounced in women and Southern Europe.

Association between alcohol consumption and cancers in the Chinese population--a systematic review and meta-analysis

BACKGROUND

Alcohol consumption is increasing worldwide and is associated with numerous cancers. This systematic review examined the role of alcohol in the incidence of cancer in the Chinese population.

METHODS

Medline/PubMed, EMBASE, CNKI and VIP were searched to identify relevant studies. Cohort and case-control studies on the effect of alcohol use on cancers in Chinese were included. Study quality was evaluated using the Newcastle-Ottawa Scale. Data were independently abstracted by two reviewers. Odds ratios (OR) or relative risks (RR) were pooled using RevMan 5.0. Heterogeneity was evaluated using the Q test and I-squared statistic. P<.01 was considered statistically significant.

RESULTS

Pooled results from cohort studies indicated that alcohol consumption was not associated with gastric cancer, esophageal cancers (EC) or lung cancer. Meta-analysis of case-control studies showed that alcohol consumption was a significant risk factor for five cancers; the pooled ORs were 1.79 (99% CI, 1.47-2.17) EC, 1.40 (99% CI, 1.19-1.64) gastric cancer, 1.56 (99% CI, 1.16-2.09) hepatocellular carcinoma, 1.21 (99% CI, 1.00-1.46) nasopharyngeal cancer and 1.71 (99% CI, 1.20-2.44) oral cancer. Pooled ORs of the case-control studies showed that alcohol consumption was protective for female breast cancer and gallbladder cancer: OR 0.76 (99% CI, 0.60-0.97) and 0.70 (99% CI, 0.49-1.00) respectively. There was no significant correlation between alcohol consumption and lung cancer, colorectal cancer, pancreatic cancer, cancer of the ampulla of Vater, prostate cancer or extrahepatic cholangiocarcinoma. Combined results of case-control and cohort studies showed that alcohol consumption was associated with 1.78- and 1.40-fold higher risks of EC and gastric cancer but was not significantly associated with lung cancer.

CONCLUSIONS

Health programs focused on limiting alcohol intake may be important for cancer control in China. Further studies are needed to examine the interaction between alcohol consumption and other risk factors for cancers in Chinese and other populations.

Alcohol drinking and colorectal cancer risk: an overall and dose-response meta-analysis of published studies

BACKGROUND

The International Agency for Research on Cancer (IARC) concluded that alcohol consumption is related to colorectal cancer (CRC). However, several issues remain unresolved, including quantification of the association for light (≤1 drink/day) and moderate (2-3 drinks/day) alcohol drinking, investigation of the dose-response relationship, and potential heterogeneity of effects by sex, colorectal site, and geographical region.

METHODS

Twenty-seven cohort and 34 case-control studies presenting results for at least three categories of alcohol intake were identified from a PubMed search of articles published before May 2010. The summary relative risks (RRs) were estimated by the random effects model. Second-order fractional polynomials and random effects meta-regression models were used for modeling the dose-risk relation.

RESULTS

The RRs were 1.21 [95% confidence interval (CI) 1.13-1.28] for moderate and 1.52 (95% CI 1.27-1.81) for heavy (≥4 drinks/day) alcohol drinking. The RR for moderate drinkers, compared with non-/occasional drinkers, was stronger for men (RR = 1.24, 95% CI 1.13-1.37) than for women (RR = 1.08, 95% CI 1.03-1.13; P(heterogeneity) = 0.02). For heavy drinkers, the association was stronger in Asian studies (RR = 1.81, 95% CI 1.33-2.46; P(heterogeneity) = 0.04). The dose-risk analysis estimated RRs of 1.07 (95% CI 1.04-1.10), 1.38 (95% CI 1.28-1.50), and 1.82 (95% CI 1.41-2.35) for 10, 50, and 100 g/day of alcohol, respectively.

CONCLUSIONS

This meta-analysis provides strong evidence for an association between alcohol drinking of >1 drink/day and colorectal cancer risk.

Cigarette smoking and colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition study

BACKGROUND & AIMS

There has been consistent evidence for a relationship between smoking and colorectal cancer (CRC), although it is not clear whether the colon or rectum is more sensitive to the effects of smoking. We investigated the relationships between cigarette smoking and risk of CRC and tumor location.

METHODS

We analyzed data from 465,879 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) study; 2741 developed CRC during the follow-up period (mean, 8.7 years). Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

The risk of colon carcinoma was increased among ever smokers (HR, 1.18; 95% CI, 1.06-1.32) and former cigarette smokers (HR, 1.21; 95% CI, 1.08-1.36), compared with never smokers; the increased risk for current smokers was of borderline significance (HR, 1.13; 95% CI, 0.98-1.31). When stratified for tumor location, the risk of proximal colon cancer was increased for former (HR, 1.25; 95% CI, 1.04-1.50) and current smokers (HR, 1.31; 95% CI, 1.06-1.64), but the risks for cancers in the distal colon or rectum were not. Subsite analyses showed a nonsignificant difference between the proximal and distal colon (P = .45) for former smokers and a significant difference for current smokers (P = .02). For smokers who had stopped smoking for at least 20 years, the risk of developing colon cancer was similar to that of never smokers.

CONCLUSIONS

Ever smokers have an increased risk of colon cancer, which appeared to be more pronounced in the proximal than the distal colon location.

Lifestyle, occupational, and reproductive factors and risk of colorectal cancer

PURPOSE

Lifestyle factors and environmental exposures might help explain the risk of colorectal carcinoma in countries where the incidence is low, but unique patterns of young onset and a high proportion of rectal cancer exist.

METHODS

We obtained detailed lifestyle information from 421 patients with colorectal cancer and 439 hospital-controls in Egypt. Logistic regression models were computed to evaluate the risk factors of colorectal carcinoma.

RESULTS

A history of pesticide exposure and more frequently eating food directly from farms were significantly associated with a higher risk of colorectal carcinoma (odds ratio = 2.6; 95% CI = 1.1-5.9, and odds ratio = 4.6; 95% CI = 1.5-14.6, respectively). Parous women who reported 7 or more live births or breastfed for 19 months or longer per live birth had a significantly lower risk for colorectal carcinoma (odds ratio = 0.3; 95% CI = 0.2-0.7, and odds ratio = 0.2; 95% CI = 0.1-0.4, respectively). Compared with patients aged 40 years or older, industrial exposures were more common in younger patients (P = .05).

CONCLUSIONS

Agricultural and industrial exposures were associated with increased risk of colorectal carcinoma, whereas prolonged lactation and increased parity were inversely associated with colorectal carcinoma in women. Further research to elucidate the biological role of intense environmental and industrial exposures and reproductive factors including lactation may further clarify the etiology of colorectal cancer.

Gender and alcohol consumption: patterns from the multinational GENACIS project

AIMS

To evaluate multinational patterns of gender- and age-specific alcohol consumption.

DESIGN AND PARTICIPANTS

Large general-population surveys of men's and women's drinking behavior (n's > 900) in 35 countries in 1997-2007 used a standardized questionnaire (25 countries) or measures comparable to those in the standardized questionnaire.

MEASUREMENTS

Data from men and women in three age groups (18-34, 35-49, 50-65) showed the prevalence of drinkers, former drinkers, and lifetime abstainers; and the prevalence of high-frequency, high-volume, and heavy episodic drinking among current drinkers. Analyses examined gender ratios for prevalence rates and the direction of changes in prevalence rates across age groups.

FINDINGS

Drinking per se and high-volume drinking were consistently more prevalent among men than among women, but lifetime abstention from alcohol was consistently more prevalent among women. Among respondents who had ever been drinkers, women in all age groups were consistently more likely to have stopped drinking than men were. Among drinkers, the prevalence of high-frequency drinking was consistently greatest in the oldest age group, particularly among men. Unexpectedly, the prevalence of drinking per se did not decline consistently with increasing age, and declines in high-volume and heavy episodic drinking with increasing age were more typical in Europe and English-speaking countries.

CONCLUSIONS

As expected, men still exceed women in drinking and high-volume drinking, although gender ratios vary. Better explanations are needed for why more women than men quit drinking, and why aging does not consistently reduce drinking and heavy drinking outside Europe and English-speaking countries.

Cigarette smoking and the risk of colorectal cancer: a meta-analysis of prospective cohort studies

BACKGROUND & AIMS

Smoking has been implicated in many malignant diseases, but its association with colorectal cancer (CRC) is controversial. We quantitatively evaluated the relation between smoking and incidence of CRC in a meta-analysis of cohort studies.

METHODS

Full publications of prospective cohort studies were identified in MEDLINE and EMBASE from 1950 to 2008. Subjects were classified as current smokers, former smokers, or never smokers. The quantity of smoking was assessed by number of cigarettes per day, years of smoking, and pack-years. The reported relative risks of CRC were pooled by random-effects model. Sensitivity analysis was conducted, and publication bias was evaluated.

RESULTS

A total of 1,463,796 subjects were recruited in 28 prospective cohorts from America, Europe, and Asia, with median follow-up of 13 years (range, 4-30 years). Current smokers showed a modestly higher risk of CRC (relative risk [RR], 1.20; 95% confidence interval [CI], 1.10-1.30) than never smokers. The risk of CRC among male smokers (RR, 1.38; 95% CI, 1.22-1.56) was more significant than among female smokers (RR, 1.06; 95% CI, 0.95-1.19). Rectal cancer was more closely related to smoking (RR, 1.36; 95% CI, 1.15-1.61) than colonic cancer. Former smokers still carried a higher CRC risk than never smokers. The increased risk of CRC was related to cigarettes per day, longer years of smoking, or larger pack-years.

CONCLUSIONS

Smoking was associated with a significantly increased risk of CRC. The associated risk was higher for men and for rectal cancers. The association of tobacco consumption and CRC risk appeared to be dose-related.

Risk factors for sporadic colorectal cancer in southern Chinese

AIM: To investigate the role of smoking, alcohol drinking, family history of cancer, and body mass index (BMI) in sporadic colorectal cancer in southern Chinese.

METHODS: A hospital-based case-control study was conducted from July 2002 to December 2008. There were 706 cases and 723 controls with their sex and age (within 5 years) matched. An unconditional logistic regression model was used to analyze the association between smoking, alcohol drinking, family history of cancer, BMI and sporadic colorectal cancer.

RESULTS: No positive association was observed between smoking status and sporadic colorectal cancer risk. Compared with the non alcohol drinkers, the current and former alcohol drinkers had an increased risk of developing sporadic colorectal cancer (CRC) (adjusted OR = 8.61 and 95% CI = 6.15-12.05; adjusted OR = 2.30, 95% CI = 1.27-4.17). Moreover, the increased risk of developing sporadic CRC was significant in those with a positive family history of cancer (adjusted OR = 1.62, 95% CI = 1.12-3.34) and in those with their BMI ≥ 24.0 kg/m² (adjusted OR = 1.39, 95% CI = 1.10-1.75). Stratification analysis showed that the risk of developing both colon and rectal cancers was increased in current alcohol drinkers (adjusted OR = 7.60 and 95% CI = 5.13-11.25; adjusted OR = 7.52 and 95% CI = 5.13-11.01) and in those with their BMI ≥ 24.0 kg/m² (adjusted OR = 1.38 and 95% CI = 1.04-1.83; adjusted OR = 1.35 and 95% CI = 1.02-1.79). The risk of developing colon cancer, but not rectal cancer, was found in former alcohol drinkers and in those with a positive family history of cancer (adjusted OR = 2.51 and 95% CI = 1.24-5.07; adjusted OR = 1.82 and 95% CI = 1.17-2.82).

CONCLUSION: Alcohol drinking, high BMI (≥ 24.0 kg/m²) and positive family history of cancer are the independent risk factors for colorectal cancer in southern Chinese.

A prospective cohort study of rectal cancer risk in relation to active cigarette smoking and passive smoke exposure

PURPOSE

The present investigation prospectively examined active cigarette smoking and household passive smoke exposure and the risk of developing rectal cancer.

METHODS

Cigarette smoking data were collected on all household members during two private censuses in Washington County, Maryland. These two cohorts were followed up, one cohort from 1963-1978 and the other from 1975-1994 for first-time diagnoses of rectal cancer. We identified 148 and 169 rectal cancer cases in the 1963 and 1975 cohorts, respectively. Relative risks were estimated by means of Poisson regression models.

RESULTS

In men, the adjusted relative risks (aRR) and 95% confidence intervals (CI) for the association between current smoking and rectal cancer were 3.1 (1.2-7.8) in the 1963 cohort and 1.8 (0.9-3.7) in the 1975 cohort; the corresponding aRRs in women were 0.9 (0.5-1.8) and 1.6 (0.9-3.8) in the 1963 and 1975 cohorts, respectively. In nonsmokers, household passive smoke exposure was strongly associated with rectal cancer among men in the 1963 cohort (aRR = 5.8; 1.8-18.4) but not the 1975 cohort (aRR = 1.1; 0.2-5.0). In women, household passive exposure was not strongly associated with rectal cancer in either cohort.

CONCLUSIONS

The results of our study suggest that active cigarette smoking may contribute to rectal cancer risk, but inconsistencies in the findings preclude drawing strong, clear-cut inferences.

Alcohol dehydrogenase and aldehyde dehydrogenase polymorphisms and colorectal cancer: the Fukuoka Colorectal Cancer Study

Alcohol dehydrogenase and aldehyde dehydrogenase are key enzymes in alcohol metabolism and therefore may be of importance to colorectal cancer development. The present case-control study was conducted to determine the influence of ADH2, ADH3 and ALDH2 polymorphisms in Fukuoka, Japan, with 685 incident cases of histologically confirmed colorectal adenocarcinomas and 778 community controls selected randomly from the study area. Alcohol use was ascertained by in-person interview. Statistical adjustment was made for sex, age class, area, and alcohol use. Individuals with the allele 47Arg of the ADH2 polymorphism (slow metabolizers) had a statistically significant increase in risk, with an adjusted OR of 1.32 (95% CI = 1.07-1.63), compared with those having the ADH2*47His/His genotype. This association was not affected by the level of alcohol consumption. The ADH3 polymorphism showed no measurable association with the risk of colorectal cancer on either overall analysis or stratified analysis with alcohol use. The heterozygous ALDH2*487Glu/Lys genotype was not associated with an increase in the risk of colorectal cancer (adjusted OR 0.89, 95% CI = 0.71-1.13) compared with the ALDH2*487Glu/Glu genotype. Rather unexpectedly, the homozygous ALDH2*487Lys/Lys genotype was related to a statistically significantly decreased risk of colorectal cancer (adjusted OR 0.55, 95% CI = 0.33-0.93). It is unlikely that acetaldehyde metabolism determined by ALDH2 polymorphism contributes to the risk of colorectal cancer, whereas the role of ADH2 polymorphism deserves further investigation.

When risk factors combine: the interaction between alcohol and smoking for aerodigestive cancer, coronary heart disease, and traffic and fire injury

BACKGROUND

Alcohol and tobacco are responsible for a significant amount of burden of disease, but some diseases may be a result of the interaction between these two risk factors.

METHODS

Systematic literature review identified articles on the interaction of alcohol and smoking on a number of outcomes related to both risk behaviours.

RESULTS

The interaction of smoking and alcohol significantly increases risk for aerodigestive cancers, and may increase risk for traffic injury and fire injury, but there were very few quality studies on injury. The indication that the cardioprotective effect of alcohol on coronary heart disease is only valid for smokers, but this result is inconclusive because of small evidence base.

CONCLUSIONS

The interaction between smoking and alcohol consumption seems to be responsible for a significant amount of disease. Unfortunately, little is known on the mechanisms and details of this interaction on disease outcomes. Future studies, especially for coronary heart disease and injury outcomes, are warranted.

National Institute on Alcohol Abuse and Alcoholism Report on Moderate Drinking

In support of the 2005 update of the U.S. Department of Agriculture/U.S. Department of Health and Human Services Dietary Guidelines, the National Institute on Alcohol Abuse and Alcoholism was asked to assess the strength of the evidence related to health risks and potential benefits of moderate alcohol consumption, with particular focus on the areas of cardiovascular disease, breast cancer, obesity, birth defects, breastfeeding, and aging. The findings were reviewed by external researchers with extensive research backgrounds on the consequences and benefits of alcohol consumption. This report now serves as the National Institutes of Health's formal position paper on the health risks and potential benefits of moderate alcohol use.

Association of Fluids From Beverages With Risk of Rectal Cancer

Little information is available about how fluid intake from beverages and sources of fluid intake influence risk of rectal cancer. We examined these associations with risk of incident rectal cancer in a population-based case-control study of 952 cases and 1,205 controls living in northern California and Utah. We also determined if intake of fiber (soluble and insoluble), physical activity, and nonsteroidal anti-inflammatory medications (NSAIDs) or aspirin modified the associations between fluid intake and rectal cancer. We identified a modest inverse association of water intake (odds ratio, OR = 0.70; 95% confidence interval, CI = 0.48, 1.02) and total fluid intake (high vs. low OR = 0.70; 95% CI = 0.46, 1.06) with risk of rectal cancer in men and a positive association with juice among women (high vs. low OR = 1.56; 95% CI = 1.00, 2.41). Risk of rectal cancer increased nonsignificantly among men with beer consumption, among women with high white wine use, and among men and women with high long-term alcohol use. NSAIDs modified the association of alcohol consumption with rectal cancer: 1) risk associated with beer increased among men who did not take NSAIDs and had a high beer intake (OR = 1.60; 95% CI = 1.08, 2.39) and 2) risk associated with long-term alcohol intake increased in a linear fashion in women who did not use NSAIDs (OR = 1.98; 95% CI = 1.15, 3.40). Risk of rectal cancer increased among estrogen-negative women if they consumed any beer or white wine but decreased among estrogen-positive women with beer. In men, low intake of water and low insoluble fiber intake were associated with increased risk of rectal cancer beyond that of either factor alone (OR = 1.82; 95% CI = 1.11, 3.00). The interactions of fiber with water intake suggest that bowel motility may be the mechanism responsible for modification of rectal cancer risk for water. Associations of alcohol to risk for rectal cancer may be related to cellular hyperproliferation and may be modified by NSAID use.

Molecular epidemiology of colon cancer

Colorectal cancer appears to have rapidly increased over the past two decades in Korea. Environmental factors, characterized by a western life style, seem to be closely related to the increased risk of colorectal cancer. Higher intakes of meat, a lower vegetable intake, a lack of physical activity, obesity, and alcohol drinking have been suggested to be risk factors for colorectal cancer in the numerous epidemiologic studies. Several specific associations have also been observed between genetic polymorphisms and colorectal cancer. Moreover, it has been postulated that environmental factors and a genetic predisposition work in concert in colorectal cancer development. A stronger association between red meat intake and colorectal cancer among those with rapid acetylators at either the NAT1 or NAT2 locus was reported, particularly for colorectal cancer associated with K-ras mutations. The protective effect of the homozygous variant TT form of the MTHFR genotype on the risk of colon cancer seems to be modified by the level of methyl diets, i.e., by folate, which has a protective effect, or conversely by alcohol. The insulin-related pathway, which possibly explains at a mechanistic level the effect of physical activity and obesity on colon cancer, appears to be a common denominator in colon cancer and in other metabolic disorders, such as diabetes mellitus and dyslipidemia. Hyperinsulinemia has been proposed as an explanation for the association between a Western lifestyle and colon cancer risk. Further studies, that incorporate both genetic and environmental factors, are needed to fully explain and identify the underlying pathway of colorectal carcinogenesis.

Relation of cigarette smoking and alcohol use to colorectal adenomas by subsite: the self-defense forces health study

While smoking has consistently been shown to be related to increased risk of colorectal adenomas, few studies have addressed the association between smoking and site-specific colorectal adenomas. The reported association between alcohol use and colorectal adenomas has been inconsistent. We evaluated risks of adenomas at the proximal colon, distal colon, and rectum in relation to cigarette smoking and alcohol use, and their interaction. Subjects were 754 cases with histologically proven colorectal adenomas and 1547 controls with normal colonoscopy among male officials of the Self-Defense Forces (SDF) undergoing total colonoscopy at two SDF hospitals. Statistical adjustment was made for hospital, rank, body mass index, physical activity, and either smoking or alcohol drinking. Cigarette smoking was significantly associated with an increased risk of adenomas, regardless of the location of the adenomas, but the increased risk associated with smoking was more pronounced for rectal adenomas. Alcohol use was associated with moderately increased risks of distal colon and rectal adenomas, but not of proximal colon adenomas. Cigarette smoking, but not alcohol drinking, was associated with greater increases in the risk of large adenomas and of multiple adenomas across the colorectum. There was no measurable interaction of cigarette smoking and alcohol drinking on colorectal adenomas. The findings corroborate an increased risk of colorectal adenomas associated with smoking and a weak association between alcohol use and colorectal adenomas. Further studies are needed to confirm whether smoking is more strongly related to rectal adenomas, large adenomas, or multiple adenomas.

Risk factors for colorectal cancer

Colorectal cancer is one of the most common cancers in human population. It causes significant morbidity and mortality in our country. The incidence of colorectal cancer increases in the fifth decade of life. The aim of this study was to evaluate the association between colorectal cancer and potential risk factors. A case-control study of colorectal cancer was carried out between 1998 and 1999 in Clinical Center of Serbia, Center for Digestive Surgery. A total of 100 cases of newly diagnosed patients with colorectal cancer confirmed by histopathology and an equal number of controls, individually matched by gender and age (+/-5 years), were chosen from patients from the same hospital with no history of cancer at all. McNemar test and conditional logistic regression were used in the analysis. According to logistic regression analysis the following risk factors were independently related with the occurrence of colorectal cancer: cigarette smoking, alcohol consumption, and diet rich in red meat and fat promote the carcinogenic process; food rich in vegetables, fruits, grains, vitamin C, physical activity, and oral contraceptive use inhibit the same process. A family history of cancer and long standing inflammatory bowel diseases also have significant role. There is convincing evidence that nutrition affects colorectal carcinogenesis in a complex fashion.