Principal component analysis of dietary and lifestyle patterns in relation to risk of subtypes of esophageal and gastric cancer

Association between priori and posteriori dietary patterns and gastric cancer risk: an updated systematic review and meta-analysis of observational studies

An increasing number of epidemiological studies have explored the relationship between the risk of gastric cancer and specific dietary patterns, but the findings remain inconclusive. We, therefore, performed this comprehensive systematic review and meta-analysis to analyze the available evidence regarding the associations between a priori and a posteriori dietary patterns and the risk of gastric cancer. A systematic search of six electronic databases, including PubMed, Web of Science, EBSCO, Scopus, China National Knowledge Infrastructure (CNKI), and Wanfang Data, was carried out to retrieve the relevant articles published up to March 2024. Thirty-six studies (10 cohort and 26 case-control studies) with a total of 2 181 762 participants were included in the final analyses. Combining 15 effect sizes extracted from 12 articles, we observed a reduced risk of gastric cancer in the highest versus the lowest categories of the Mediterranean diet [relative risk (RR), 0.72; 95% confidence interval (CI), 0.61-0.85; P < 0.001]. Combining 11 effect sizes from 10 articles (involving 694 240 participants), we found that the highest Dietary Inflammatory Index scores were significantly associated with an increased risk of gastric cancer (RR, 1.32; 95% CI, 1.11-1.57; P < 0.001). A reduced risk of gastric cancer was shown for the highest compared with the lowest categories of healthy dietary pattern (RR, 0.78; 95% CI, 0.67-0.91; P = 0.002). Conversely, the highest adherence to the Western dietary pattern was associated with an increased risk of gastric cancer (RR, 1.33; 95% CI, 1.19-1.49; P < 0.001). Our study demonstrated that the Mediterranean diet and a healthy dietary pattern were associated with a decreased risk of gastric cancer. Conversely, the Dietary Inflammatory Index and Western dietary pattern were associated with an increased risk of gastric cancer.

Microbiota metabolized Bile Acids accelerate Gastroesophageal Adenocarcinoma via FXR inhibition

Background

The incidence of Barrett esophagus (BE) and Gastroesophageal Adenocarcinoma (GEAC) correlates with obesity and a diet rich in fat. Bile acids (BA) support fat digestion and undergo microbial metabolization in the gut. The farnesoid X receptor (FXR) is an important modulator of the BA homeostasis. The capacity of inhibiting cancer-related processes when activated, make FXR an appealing therapeutic target. In this work, we assess the role of diet on the microbiota-BA axis and evaluate the role of FXR in disease progression.

Results

Here we show that high fat diet (HFD) accelerated tumorigenesis in L2-IL1B mice (BE- and GEAC- mouse model) while increasing BA levels and enriching gut microbiota that convert primary to secondary BA. While upregulated in BE, expression of FXR was downregulated in GEAC in mice and humans. In L2-IL1B mice, FXR knockout enhanced the dysplastic phenotype and increased Lgr5 progenitor cell numbers. Treatment of murine organoids and L2-IL1B mice with the FXR agonist obeticholic acid (OCA) deacelerated GEAC progression.

Conclusion

We provide a novel concept of GEAC carcinogenesis being accelerated via the diet-microbiome-metabolome axis and FXR inhibition on progenitor cells. Further, FXR activation protected with OCA ameliorated the phenotype in vitro and in vivo, suggesting that FXR agonists have potential as differentiation therapy in GEAC prevention.

Hotspots and trends of risk factors in gastric cancer: A visualization and bibliometric analysis

BACKGROUND

The lack of specific symptoms of gastric cancer (GC) causes great challenges in its early diagnosis. Thus it is essential to identify the risk factors for early diagnosis and treatment of GC and to improve the survival rates.

AIM

To assist physicians in identifying changes in the output of publications and research hotspots related to risk factors for GC, constructing a list of key risk factors, and providing a reference for early identification of patients at high risk for GC.

METHODS

Research articles on risk factors for GC were searched in the Web of Science core collection, and relevant information was extracted after screening. The literature was analyzed using Microsoft Excel 2019, CiteSpace V, and VOSviewer 1.6.18.

RESULTS

A total of 2514 papers from 72 countries and 2507 research institutions were retrieved. China (n = 1061), National Cancer Center (n = 138), and Shoichiro Tsugane (n = 36) were the most productive country, institution, or author, respectively. The research hotspots in the study of risk factors for GC are summarized in four areas, namely: Helicobacter pylori (H. pylori) infection, single nucleotide polymorphism, bio-diagnostic markers, and GC risk prediction models.

CONCLUSION

In this study, we found that H. pylori infection is the most significant risk factor for GC; single-nucleotide polymorphism (SNP) is the most dominant genetic factor for GC; bio-diagnostic markers are the most promising diagnostic modality for GC. GC risk prediction models are the latest current research hotspot. We conclude that the most important risk factors for the development of GC are H. pylori infection, SNP, smoking, diet, and alcohol.

The medium-term impact of a micronutrient powder intervention on anemia among young children in Rural China

BACKGROUND

Poor development of young children is a common issue in developing countries and it is well established that iron deficiency anemia is one of the risk factors. Research has shown that iron deficiency is a common micronutrient deficiency among children in rural China and can result in anemia. A previous paper using data from the same trial as those used in the current study, but conducted when sample children were younger, found that after 6 months of providing caregivers of children 6-11 months of age free access to iron-rich micronutrient powder (MNP) increased the hemoglobin concentrations (Hb) of their children. However, no effects were found 12 and 18 months after the intervention. The current study followed up the children four years after the start of the original intervention (when the children were 4-5 years old) and aims to assess the medium-term impacts of the MNP program on the nutritional status of the sample pre-school-aged children, including their levels of Hb, the prevalence of anemia, and the dietary diversity of the diets of the children.

METHODS

At baseline, this study sampled 1,802 children aged 6-11 months in rural Western China. The intervention lasted 18 months. In this medium-term follow-up study that successfully followed 81% (n = 1,464) of children (aged 49-65 months) from the original study population 4 years after the start of the intervention, we used both intention-to-treat (ITT) effect and average treatment on the treated effect (ATT) analyses to assess the medium-term impacts of the MNP distribution program on the nutritional status of sample children.

RESULTS

The ITT analysis shows that the MNP intervention decreased the prevalence of anemia of young children in the medium run by 8% (4 percentage points, p < 0.1). The ATT analysis shows that consuming 100 (out of 540) MNP sachets during the initial intervention led to a decrease in anemia of 4% (2 percentage points, p < 0.1). Among children with moderate anemia at baseline (Hb < 100 g/L), the intervention reduced the probability of anemia by 45% (9 percentage points, p < 0.1), and, for those families that complied by consuming 100 (out of 540) sachets, a 25% (5 percentage points, p < 0.05) reduction in the anemia rate was found. The MNP intervention also led to a persistent increase in dietary diversity among children that were moderately anemic at baseline. The results from the quantile treatment effect analysis demonstrated that children with lower Hb levels at baseline benefited relatively more from the MNP intervention.

CONCLUSIONS

The findings of the current study reveal that the MNP intervention has medium-term effects on the nutritional status of children in rural China. The impacts of the MNP program were relatively higher for children that initially had more severe anemia levels. Hence, the implications of this study are that programs that aim to increase caregiver knowledge of nutrition and improve their feeding practices should be encouraged across rural China. Families, policymakers, and China's society overall need to continue to pay more attention to problems of childhood anemia in rural areas. This is particularly crucial for families with moderately anemic children at an early age as it can significantly contribute to improving the anemia status of children across rural areas of China.

TRIAL REGISTRATION

ISRCTN44149146 (15/04/2013).

Lifestyle Patterns in the Late Postoperative Period of Bariatric Surgery: a Descriptive Analysis of the CINTO Study

BACKGROUND

The behavior of patients undergoing metabolic bariatric surgery (MBS) has been widely investigated to better understand their attitudes and to formulate effective advisory strategies. Although these elements have been studied separately, the magnitude of these behaviors still needs to be determined from a combined factors approach. This study aimed to identify the lifestyle patterns of patients who underwent MBS 5 or more years ago.

METHODS

In this observational study, 123 patients who underwent MBS at least 5 years ago were included. Anthropometric data, sociodemographic profile, dietary intake, physical activity level, sleeping, smoking, and alcohol consumption were collected for all participants. Lifestyle pattern was evaluated using principal component analysis (PCA) and the Kaiser-Meyer-Olkin (KMO) index was applied to evaluate data factorability.

RESULTS

PCA identified two patterns of behavior adopted by the participants in the late postoperative (PO) period (more than 5 years PO) of MBS. In the first pattern, a positive correlation was found between consumption of ultra-processed foods (r = 0.459), risky consumption of alcoholic beverages (r = 0.630), and tobacco use (r = 0.584). In the second, a positive correlation was observed between the consumption of unprocessed or minimally processed foods (r = 0.692) and more sleep time per day (r = 0.654).

CONCLUSION

After 5 years of PO, combined behavior analysis revealed healthy and unhealthy lifestyle patterns, which points to the relevance of permanent clinical follow-up of these patients to ensure the best health status.

The low dimensionality of post-stroke cognitive deficits: it's the lesion anatomy!

For years, dissociation studies on neurological single-case patients with brain lesions were the dominant method to infer fundamental cognitive functions in neuropsychology. In contrast, the association between deficits was considered to be of less epistemological value. Still, associational computational methods for dimensionality reduction-such as principal component analysis or factor analysis-became popular for the identification of fundamental cognitive functions and to understand human cognitive brain architecture from post-stroke neuropsychological profiles. In the present in silico study with lesion imaging of 300 stroke patients, we investigated the dimensionality of artificial simulated neuropsychological profiles that exclusively contained independent fundamental cognitive functions without any underlying low-dimensional cognitive architecture. Still, the anatomy of stroke lesions alone was sufficient to create a dependence between variables that allowed a low-dimensional description of the data with principal component analysis. All criteria that we used to estimate the dimensionality of data, including the Kaiser criterion, were strongly affected by lesion anatomy, while the Joliffe criterion provided the least affected estimates. The dimensionality of profiles was reduced by 62-70% for the Kaiser criterion, up to the degree that is commonly found in neuropsychological studies on actual cognitive measures. The interpretability of such low-dimensional factors as deficits of fundamental cognitive functions and their provided insights into human cognitive architecture thus seem to be severely limited, and the heavy focus of current cognitive neuroscience on group studies and associations calls for improvements. We suggest that qualitative criteria and dissociation patterns could be used to refine estimates for the dimensionality of the cognitive architecture behind post-stroke deficits. Further, given the strong impact of lesion anatomy on the associational structure of data, we see the need for further optimization of interpretation strategies of computational factors in post-stroke lesion studies of cognitive deficits.

Healthy Diet, Polygenic Risk Score, and Upper Gastrointestinal Cancer Risk: A Prospective Study from UK Biobank

Dietary and genetic factors are considered to be associated with UGI cancer risk. However, examinations of the effect of healthy diet on UGI cancer risk and the extent to which healthy diet modifies the impact of genetic susceptibility on UGI cancer remains limited. Associations were analyzed through Cox regression of the UK Biobank data (n = 415,589). Healthy diet, based on “healthy diet score,” was determined according to fruit, vegetables, grains, fish, and meat consumption. We compared adherence to healthy diet and the risk of UGI cancer. We also constructed a UGI polygenic risk score (UGI-PRS) to assess the combined effect of genetic risk and healthy diet. For the results high adherence to healthy diet reduced 24% UGI cancer risk (HR high-quality diet: 0.76 (0.62–0.93), p = 0.009). A combined effect of high genetic risk and unhealthy diet on UGI cancer risk was observed, with HR reaching 1.60 (1.20–2.13, p = 0.001). Among participants with high genetic risk, the absolute five-year incidence risk of UGI cancer was significantly reduced, from 0.16% to 0.10%, by having a healthy diet. In summary, healthy diet decreased UGI cancer risk, and individuals with high genetic risk can attenuate UGI cancer risk by adopting a healthy diet.

Effect of healthy lifestyle index and lifestyle patterns on the risk of mortality: A community-based cohort study

Background

Limited evidence was available on the association of the integrated effect of multidimensional lifestyle factors with mortality among Chinese populations. This cohort study was to examine the effect of combined lifestyle factors on the risk of mortality by highlighting the number of healthy lifestyles and their overall effects.

Methods

A total of 11,395 participants from the Guangzhou Heart Study (GZHS) were followed up until 1 January 2020. Individual causes of death were obtained from the platform of the National Death Registry of China. The healthy lifestyle index (HLI) was established from seven dimensions of lifestyle, and lifestyle patterns were extracted from eight dimensions of lifestyle using principal component analysis (PCA). Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard regression model.

Results

During 35,837 person-years of follow-up, 184 deaths (1.61%) were observed, including 64 from cardiovascular disease. After adjustment for confounders, HLI was associated with a 50% (HR: 0.50, 95% CI: 0.25–0.99) reduced risk of all-cause mortality when comparing the high (6–7 lifestyle factors) with low (0–2 lifestyle factors) categories. Three lifestyle patterns were defined and labeled as pattern I, II, and III. Lifestyle pattern II with higher factor loadings of non-smoking and low-level alcohol drinking was associated with a decreased risk of all-cause mortality (HR: 0.63, 95% CI: 0.43–0.92, P_–trend = 0.023) when comparing the high with low tertiles of pattern score, after adjustment for confounders. Every 1-unit increment of pattern II score was associated with a decreased risk (HR: 0.97, 95% CI: 0.95–0.99) of all-cause mortality. The other two patterns were not associated with all-cause mortality, and the association of cardiovascular mortality risk was observed with neither HLI nor any lifestyle pattern.

Conclusion

The results suggest that the more dimensions of the healthy lifestyle the lower the risk of death, and adherence to the lifestyle pattern characterized with heavier loading of non-smoking and low-level alcohol drinking reduces the risk of all-cause mortality. The findings highlight the need to consider multi-dimensional lifestyles rather than one when developing health promotion strategies.

Mediterranean Dietary Pattern is Associated with Lower Odds of Gastric Cancer: A Case-Control Study

Background

Diet pattern is an important modifiable lifestyle factor. However, epidemiological studies show that the association between dietary patterns and gastric cancer (GC) is conflicting. This study aims to assess the impact of several dietary choices on the risk of GC among newly diagnosed Jordanian patients.

Methods

A case–control study was conducted at major oncology centers and hospitals in Jordan. Study participants included 172 patients with incident gastric cancer and 314 controls. Data was collected using interview-based questionnaires. Dietary intake was estimated using a validated Arabic and reproducible food-frequency questionnaire (FFQ). Dietary patterns were derived using Principal Component Analysis (PCA). Multinomial logistic regression was used to estimate the association between dietary patterns and GC.

Results

Four dietary patterns were itemized; “Mediterranean”, “Prudent”, “Unhealthy” and “High-fruit” dietary patterns. The “Mediterranean” dietary pattern, which includes a diet rich in fresh fruits, vegetables, milk, yogurt, lentils, and olive oil was associated with a significant decrease in the odds ratio (OR) of GC for the third and fourth quartiles (OR, 0.394 (confidence interval (CI): 0.211–0.736); 0.212 (CI: 0.107–0.419), respectively) after adjusting for age, gender, body mass index, smoking, marital status, total energy intake, education level, and physical activity. While the “Unhealthy” and “Prudent” dietary patterns enhance the risk of developing GC, this risk was insignificant at any quartile. Additionally, the “High-Fruit” dietary pattern shows an insignificant protective effect against the risk of GC.

Conclusion

The “Mediterranean” dietary pattern was associated with a reduced risk of GC among Jordanians. However, the other three identified dietary patterns were not significantly associated with the risk of GC.

The Association between Dietary Vitamin C Intake and the Risk of Esophageal Cancer: An Updated Dose-Response Meta-Analysis

Although some epidemiological studies have reported the associations between vitamin C and risk of esophageal cancer, these results are inconsistent. Therefore, we performed an updated meta-analysis to explore the associations between dietary vitamin C intake and risk of esophageal cancer. We used PubMed, Embase, and the Web of Science to screen all published articles, which yielded 18 papers eligible for data extraction (involving 4,126 cases and 36,902 controls), and then pooled the odds ratios (ORs) and corresponding 95% confidence intervals (CIs) using random-effects model. As we detected the associations in highest category and the lowest type of dietary vitamin C intake, we discovered that dietary vitamin C intake was negatively correlated to the risk of esophageal cancer. The analysis of subgroup showed a significant counter proportion between vitamin C and the risk of ESCC and EAC. Moreover, the dose-analysis indicated that if increasing dietary intake of vitamin C of 50 mg/day, esophageal cancer risk dropped down 10% (OR = 0.81, 95%CI: 0.75-0.87). In summary, our study provides a comprehensive and updated epidemiological evidence to elucidate the relationships between dietary vitamin C and reduction of esophageal cancer risk. Nevertheless, we still need larger case-control and cohort studies to confirm these connections.

Dynamic Meta-data Network Sparse PCA for Cancer Subtype Biomarker Screening

Previous research shows that each type of cancer can be divided into multiple subtypes, which is one of the key reasons that make cancer difficult to cure. Under these circumstances, finding a new target gene of cancer subtypes has great significance on developing new anti-cancer drugs and personalized treatment. Due to the fact that gene expression data sets of cancer are usually high-dimensional and with high noise and have multiple potential subtypes’ information, many sparse principal component analysis (sparse PCA) methods have been used to identify cancer subtype biomarkers and subtype clusters. However, the existing sparse PCA methods have not used the known cancer subtype information as prior knowledge, and their results are greatly affected by the quality of the samples. Therefore, we propose the Dynamic Metadata Edge-group Sparse PCA (DM-ESPCA) model, which combines the idea of meta-learning to solve the problem of sample quality and uses the known cancer subtype information as prior knowledge to capture some gene modules with better biological interpretations. The experiment results on the three biological data sets showed that the DM-ESPCA model can find potential target gene probes with richer biological information to the cancer subtypes. Moreover, the results of clustering and machine learning classification models based on the target genes screened by the DM-ESPCA model can be improved by up to 22–23% of accuracies compared with the existing sparse PCA methods. We also proved that the result of the DM-ESPCA model is better than those of the four classic supervised machine learning models in the task of classification of cancer subtypes.

Assessment of Pediatric Cancer and Its Relationship to Environmental Contaminants: An Ecological Study in Idaho

The primary aim of this study was to determine the degree to which a multivariable principal component model based on several potentially carcinogenic metals and pesticides could explain the county-level pediatric cancer rates across Idaho. We contend that human exposure to environmental contaminants is one of the reasons for increased pediatric cancer incidence in the United States. Although several studies have been conducted to determine the relationship between environmental contaminants and carcinogenesis among children, research gaps exist in developing a meaningful association between them. For this study, pediatric cancer data was provided by the Cancer Data Registry of Idaho, concentrations of metals and metalloids in groundwater were collected from the Idaho Department of Water Resources, and pesticide use data were collected from the United States Geological Survey. Most environmental variables were significantly intercorrelated at an adjusted P-value <0.01 (97 out of 153 comparisons). Hence, a principal component analysis was employed to summarize those variables to a smaller number of components. An environmental burden index (EBI) was constructed using these principal components, which categorized the environmental burden profiles of counties into low, medium, and high. EBI was significantly associated with pediatric cancer incidence (P-value <0.05). The rate ratio of high EBI profile to low EBI profile for pediatric cancer incidence was estimated as 1.196, with lower and upper confidence intervals of 1.061 and 1.348, respectively. A model was also developed in the study using EBI to estimate the county-level pediatric cancer incidence in Idaho (Nash-Sutcliffe Efficiency = 0.97).

Lifestyle, WCRF/AICR Recommendations, and Esophageal Adenocarcinoma Risk: A Systematic Review of the Literature

One of the most notable changes in the epidemiology of esophageal cancer (EC) is the rising incidence and prevalence of esophageal adenocarcinoma (EAC) in developed countries. The aim of this systematic review was to collect and summarize all the available evidence regarding lifestyle, diet, and EAC risk. We searched the PubMed and Scopus databases in January 2021 for studies providing information about lifestyle, diet, WCRF/AICR recommendations, and EAC risk; published in English; without a time filter. The Newcastle-Ottawa Scale was used to assess risk of bias. The results are stratified by risk factor. A total of 106 publications were included. Half of the case-control studies were judged as high quality, whilst practically all cohort studies were judged as high quality. Body mass index and waist circumference were associated with increased EAC risk. Physical activity did not appear to have a significant direct role in EAC risk. A diet rich in fruit, vegetables, and whole grains appeared to be more protective than a Western diet. Alcohol does not seem to be related to EAC, whereas smokers, particularly heavy smokers, have an increased risk of EAC. Prevention remains the best option to avert EAC. Comprehensible and easy to follow recommendations should be provided to all subjects. Protocol ID number: CRD-42021228762, no funds received.

Prevalence and coprevalence of modifiable risk factors for upper digestive tract cancer among residents aged 40-69 years in Yangzhong city, China: a cross-sectional study

OBJECTIVES

To describe the prevalence of modifiable risk factors for upper digestive tract cancer (UDTC) and its coprevalence, and investigate relevant influencing factors of modifiable UDTC risk factors coprevalence among residents aged 40-69 years in Yangzhong city, China.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 21 175 participants aged 40-69 years were enrolled in the study. 1962 subjects were excluded due to missing age, marital status or some other selected information. Eventually, 19 213 participants were available for the present analysis.

MAIN OUTCOMES MEASURES

Prevalence and coprevalence of eight modifiable UDTC risk factors (overweight or obesity, current smoking, excessive alcohol consumption, insufficient vegetables intake, insufficient fruit intake and the consumption of pickled, fried and hot food) were analysed.

RESULTS

The prevalence of overweight/obesity, current smoking, excessive alcohol consumption, insufficient vegetables intake, insufficient fruit intake and the consumption of pickled, fried and hot food in this study was 45.3%, 24.1%, 16.2%, 66.1%, 94.5%, 68.1%, 36.0% and 88.4%, respectively. Nearly all (99.9%) participants showed one or more UDTC risk factors, 98.6% of the participants showed at least two risk factors, 92.2% of the participants had at least three risk factors and 69.7% of the participants had four or more risk factors. Multivariate logistic regression analysis revealed that men, younger age, single, higher education, higher annual family income and smaller household size were more likely to present modifiable UDTC risk factors coprevalence.

CONCLUSIONS

The prevalence and coprevalence of modifiable UDTC risk factors are high among participants in Yangzhong city. Extra attention must be paid to these groups who are susceptible to risk factors coprevalence during screening progress. Relative departments also need to make significant public health programmes that aim to decrease modifiable UDTC risk factors coprevalence among residents aged 40-69 years from high-risk areas of UDTC.

Prognostic value of microRNA-125a/b family in patients with gastric cancer: a meta-analysis

AIM

This meta-analysis was designed to reassess the prognostic and clinicopathologic values of the microRNA-125 family in GC patients.

BACKGROUND

The miR-125 family (including miR-125a, miR-125b) has been reported as being pivotal prognostic biomarkers of gastric cancer (GC). However, there is controversy about the role of the miR-125 family in predicting the progression of GC.

METHODS

The miR-125 family (including miR-125a, miR-125b) has been reported as being pivotal prognostic biomarkers of gastric cancer (GC). However, there is controversy about the role of the miR-125 family in predicting the progression of GC.

RESULTS

The electronic databases of PubMed, ISI Web of Science, Scopus, and Cochrane Library were systematically searched for relevant studies. Overall survival (OS) rate as the primary outcome from each study was extracted. The overall hazard ratio (HR or survival rate in patients with GC) and odds ratio (OR) with 95% confidence interval (CI) was calculated to evaluate the association between miR-125 family expression and prognosis and susceptibility to gastric cancer. The quality of evidence was evaluated using the Newcastle-Ottava Scale (NOS). The extracted data was combined based on the random-effects model.

CONCLUSION

The low expression of miR-125 family predicts poor OS in GC patients. Thus, the miR-125 family may be helpful as a potential biomarker for the prognosis of gastric cancer.

Dietary patterns and gastric cancer risk in a Korean population: a case-control study

PURPOSE

Dietary pattern analysis has been considered as an approach to capture the complex interactions of overall diet, which are often lost in studies of single dietary components (e.g., foods and nutrients). The aim of this study was to identify the major dietary patterns of Koreans via principal component analysis based on the food groups and to investigate the association between dietary patterns and gastric cancer (GC) risk.

METHODS

In this study, participants were recruited from the National Cancer Center, Korea. Among them, 415 cases were diagnosed with early GC, and 830 controls were age- and sex-matched at a ratio of 1:2. To determine the subjects' dietary patterns, 34 predefined food groups based on the 106-item semiquantitative food frequency questionnaire (SQFFQ) were used. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated across the tertiles of dietary pattern scores using logistic regression models.

RESULTS

The two dietary patterns derived in this study were named westernized and prudent. Those patterns explained 24.83% of the total variation in food intake. Higher scores on the prudent pattern was inversely associated with the risk of GC (OR [95% CI] for the highest vs. lowest tertiles: 0.58 [0.41-0.84], p for trend = 0.004).

CONCLUSION

Our findings suggest that adherence to the prudent dietary pattern represented by high loadings of vegetables and fruits, was associated with lower GC risk. Further studies with a prospective design and larger sample sizes are necessary.

A nomogram to predict outcomes of lung cancer patients after pneumonectomy based on 47 indicators

Aims

We aimed to establish a nomogram for lung cancer using patients' characteristics and potential hematological biomarkers.

Methods

Principle component analysis was used to reduce the dimensions of the data, and each component was transformed into categorical variables based on cutoff values obtained using the X‐tile software. Multivariate analysis was used to determine potential prognostic biomarkers. Five components were used in the predictive nomogram. Internal validation of the model was performed by bootstrapping of samples, while external validation was performed on a separate cohort from Shandong Cancer Hospital. The predictive accuracy of the model was measured by concordance index and risk group stratification. Decision curve analysis was performed to evaluate the net benefit of the models.

Results

One hundred patients in the Discovery group and 111 patients in the Validation group were retrospectively analyzed in this study. Forty‐seven indexes were sorted into eight subgroups. Five components based on cox regression analysis were enrolled into the predictive nomogram. The nomogram prediction of the probability of 3‐ and 5‐year overall survival was in great concordance with the actual observations. Of interest, the nomogram allowed better risk stratification of patients and better accuracy in predicting patients' survival compared with pathological tumor‐node‐metastasis staging system.

Conclusion

A nomogram was established for prognosis of lung cancer, which can be used for treatment selection and clinical care management.

Preventable lifestyle and eating habits associated with gastric adenocarcinoma: A case-control study

Background: Besides the well-established risk factors for gastric adenocarcinoma (GaC), many other etiological factors remain largely unexplored. This large comprehensive case-control study aimed to investigate the preventable lifestyle and eating habits associated with GaC.

Methods: Consecutive patients with primary microscopically-confirmed GaC diagnosed in 2016-2018 were matched by sex, age, height, and socioeconomic status at a 1:1 ratio with healthy controls. Association of GaC versus control with investigated factors was assessed using the multivariable-adjusted conditional logistic regression for paired samples.

Results: Together 302 GaC patients and 302 healthy controls were investigated. Participants receiving higher education and those eating majorly vegetables had less frequently GaC. The majorly frying cooking habit was associated with a higher incidence of GaC. People complaining about poor sleep quality had more often GaC. The more often one smoked, the more often he/she had GaC. A higher frequency for having pickled food was associated with more frequent GaC, while having more frequently vegetables/fruit, beans, or kelps was associated with less often GaC. A greater preference for sour or bitter taste was associated with less frequent GaC. The frequencies of thin liquid intake after meal, swallowing hot food without adequate cooling, doing other things while eating, eating overnight food, and eating midnight snack were all positively associated with GaC, while going to bed regularly was associated with less often GaC.

Conclusions: Education level, sleep quality, smoking, the frequencies of use of several foods and seasonings, the preference for specific tastes, and various eating and living habits were associated with GaC. The findings offer important hints for further prospective investigations and for easy effective GaC-preventative strategy-making.

Association Between Nitrite and Nitrate Intake and Risk of Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND Studies have shown inconsistent associations of nitrite and nitrate intake with the risk of gastric cancer or its associated mortality. We performed a meta-analysis of observational studies to evaluate the correlation of nitrite and nitrate intake with the risk of gastric cancer. MATERIAL AND METHODS We searched for studies reporting effect estimates and 95% confidence intervals (CIs) of gastric cancer in PubMed, EMBASE, and the Cochrane Library through November 2018. The summary results of the included studies were pooled using a random-effects model. RESULTS Eighteen case-control and 6 prospective cohort studies recruiting 800 321 participants were included in this study. The summary results indicated that the highest (odds ratio [OR], 1.27; 95%CI, 1.03-1.55; P=0.022) or moderate (OR: 1.12; 95%CI, 1.01-1.26; P=0.037) nitrite intake were associated with a higher risk of gastric cancer. However, we noted that high (OR, 0.81; 95%CI, 0.68-0.97; P=0.021) or moderate (OR, 0.86; 95%CI, 0.75-0.99; P=0.036) nitrate intakes were associated with a reduced risk of gastric cancer. These associations differed when stratified by publication year, study design, country, the percentage of male participants, assessment of exposure, adjusted model, and study quality. CONCLUSIONS High or moderate nitrite intake was associated with higher risk of gastric cancer, whereas high or moderate nitrate intake was correlated with lower risk of gastric cancer.

ESCC ATLAS: A population wide compendium of biomarkers for Esophageal Squamous Cell Carcinoma

Esophageal cancer (EC) is the eighth most aggressive malignancy and its treatment remains a challenge due to the lack of biomarkers that can facilitate early detection. EC is identified in two major histological forms namely - Adenocarcinoma (EAC) and Squamous cell carcinoma (ESCC), each showing differences in the incidence among populations that are geographically separated. Hence the detection of potential drug target and biomarkers demands a population-centric understanding of the molecular and cellular mechanisms of EC. To provide an adequate impetus to the biomarker discovery for ESCC, which is the most prevalent esophageal cancer worldwide, here we have developed ESCC ATLAS, a manually curated database that integrates genetic, epigenetic, transcriptomic, and proteomic ESCC-related genes from the published literature. It consists of 3475 genes associated to molecular signatures such as, altered transcription (2600), altered translation (560), contain copy number variation/structural variations (233), SNPs (102), altered DNA methylation (82), Histone modifications (16) and miRNA based regulation (261). We provide a user-friendly web interface ( http://www.esccatlas.org , freely accessible for academic, non-profit users) that facilitates the exploration and the analysis of genes among different populations. We anticipate it to be a valuable resource for the population specific investigation and biomarker discovery for ESCC.

ESCC ATLAS: A population wide compendium of biomarkers for Esophageal Squamous Cell Carcinoma

Esophageal cancer (EC) is the eighth most aggressive malignancy and its treatment remains a challenge due to the lack of biomarkers that can facilitate early detection. EC is identified in two major histological forms namely - Adenocarcinoma (EAC) and Squamous cell carcinoma (ESCC), each showing differences in the incidence among populations that are geographically separated. Hence the detection of potential drug target and biomarkers demands a population-centric understanding of the molecular and cellular mechanisms of EC. To provide an adequate impetus to the biomarker discovery for ESCC, which is the most prevalent esophageal cancer worldwide, here we have developed ESCC ATLAS, a manually curated database that integrates genetic, epigenetic, transcriptomic, and proteomic ESCC-related genes from the published literature. It consists of 3475 genes associated to molecular signatures such as, altered transcription (2600), altered translation (560), contain copy number variation/structural variations (233), SNPs (102), altered DNA methylation (82), Histone modifications (16) and miRNA based regulation (261). We provide a user-friendly web interface ( http://www.esccatlas.org , freely accessible for academic, non-profit users) that facilitates the exploration and the analysis of genes among different populations. We anticipate it to be a valuable resource for the population specific investigation and biomarker discovery for ESCC.

Principal component analysis of early alcohol, drug and tobacco use with major depressive disorder in US adults

Early alcohol, tobacco and drug use prior to 18 years old are comorbid and correlated. This study included 6239 adults with major depressive disorder (MDD) in the past year and 72,010 controls from the combined data of 2013 and 2014 National Survey on Drug Use and Health (NSDUH). To deal with multicollinearity existing among 17 variables related to early alcohol, tobacco and drug use prior to 18 years old, we used principal component analysis (PCA) to infer PC scores and then use weighted multiple logistic regression analyses to estimate the associations of potential factors and PC scores with MDD. The odds ratios (ORs) with 95% confidence intervals (CIs) were estimated. The overall prevalence of MDD was 6.7%. The first four PCs could explain 57% of the total variance. Weighted multiple logistic regression showed that PC1 (a measure of psychotherapeutic drugs and illicit drugs other than marijuana use), PC2 (a measure of cocaine and hallucinogens), PC3 (a measure of early alcohol, cigarettes, and marijuana use), and PC4 (a measure of cigar, smokeless tobacco use and illicit drugs use) revealed significant associations with MDD (OR = 1.12, 95% CI = 1.08-1.16, OR = 1.08, 95% CI = 1.04-1.12, OR = 1.13, 95% CI = 1.07-1.18, and OR = 1.15, 95% CI = 1.09-1.21, respectively). In conclusion, PCA can be used to reduce the indicators in complex survey data. Early alcohol, tobacco and drug use prior to 18 years old were found to be associated with increased odds of adult MDD.

Dietary patterns within educational groups and their association with CHD and stroke in the European Prospective Investigation into Cancer and Nutrition-Netherlands cohort

Higher-educated people often have healthier diets, but it is unclear whether specific dietary patterns exist within educational groups. We therefore aimed to derive dietary patterns in the total population and by educational level and to investigate whether these patterns differed in their composition and associations with the incidence of fatal and non-fatal CHD and stroke. Patterns were derived using principal components analysis in 36 418 participants of the European Prospective Investigation into Cancer and Nutrition-Netherlands cohort. Self-reported educational level was used to create three educational groups. Dietary intake was estimated using a validated semi-quantitative FFQ. Hazard ratios were estimated using Cox Proportional Hazard analysis after a mean follow-up of 16 years. In the three educational groups, similar 'Western', 'prudent' and 'traditional' patterns were derived as in the total population. However, with higher educational level a lower population-derived score for the 'Western' and 'traditional' patterns and a higher score on the 'prudent' pattern were observed. These differences in distribution of the factor scores illustrate the association between education and food consumption. After adjustments, no differences in associations between population-derived dietary patterns and the incidence of CHD or stroke were found between the educational groups (P interaction between 0·21 and 0·98). In conclusion, although in general population and educational groups-derived dietary patterns did not differ, small differences between educational groups existed in the consumption of food groups in participants considered adherent to the population-derived patterns (Q4). This did not result in different associations with incident CHD or stroke between educational groups.

Possible role of diet in cancer: systematic review and multiple meta-analyses of dietary patterns, lifestyle factors, and cancer risk

Context

Evidence of an association between dietary patterns derived a posteriori and risk of cancer has not been reviewed comprehensively.

Objective

The aim of this review was to investigate the relation between a posteriori-derived dietary patterns, grouped as healthy or unhealthy, and cancer risk. The relation between cancer risk and background characteristics associated with adherence to dietary patterns was also examined.

Data Sources

PubMed and Embase electronic databases were searched.

Study Selection

A total of 93 studies including over 85 000 cases, 100 000 controls, and 2 000 000 exposed individuals were selected.

Data Extraction

Data were extracted from each identified study using a standardized form by two independent authors.

Results

The most convincing evidence (significant results from prospective cohort studies) supported an association between healthy dietary patterns and decreased risk of colon and breast cancer, especially in postmenopausal, hormone receptor-negative women, and an association between unhealthy dietary patterns and increased risk of colon cancer. Limited evidence of a relation between an unhealthy dietary pattern and risk of upper aerodigestive tract, pancreatic, ovarian, endometrial, and prostatic cancers relied only on case-control studies. Unhealthy dietary patterns were associated with higher body mass index and energy intake, while healthy patterns were associated with higher education, physical activity, and less smoking. Potential differences across geographical regions require further evaluation.

Conclusions

The results suggest a potential role of diet in certain cancers, but the evidence is not conclusive and may be driven or mediated by lifestyle factors.

Association between dietary nitrate and nitrite intake and sitespecific cancer risk: evidence from observational studies

Epidemiological studies have reported inconsistent findings on the association between dietary nitrate and nitrite intake and cancer risk. We performed a meta-analysis of epidemiological studies to summarize available evidence on the association between dietary nitrate and nitrite intake and cancer risk from published prospective and case-control studies. PubMed database was searched to identify eligible publications through April 30^th, 2016. Study-specific relative risks (RRs) with corresponding 95% confidence interval (CI) from individual studies were pooled by using random- or fixed- model, and heterogeneity and publication bias analyses were conducted.

Data from 62 observational studies, 49 studies for nitrates and 51 studies for nitrites, including a total of 60,627 cancer cases were analyzed. Comparing the highest vs. lowest levels, dietary nitrate intake was inversely associated with gastric cancer risk (RR = 0.78; 95%CI = 0.67-0.91) with moderate heterogeneity (I² = 42.3%). In contrast, dietary nitrite intake was positively associated with adult glioma and thyroid cancer risk with pooled RR of 1.21 (95%CI = 1.03-1.42) and 1.52 (95%CI = 1.12-2.05), respectively. No significant associations were found between dietary nitrate/nitrite and cancers of the breast, bladder, colorectal, esophagus, renal cell, non-Hodgkin lymphoma, ovarian, and pancreas. The present meta-analysis provided modest evidence that positive associations of dietary nitrate and negative associations of dietary nitrite with certain cancers.

Re-evaluation of potassium nitrite (E 249) and sodium nitrite (E 250) as food additives

The Panel on Food Additives and Nutrient Sources added to Food (ANS) provided a scientific opinion re-evaluating the safety of potassium nitrite (E 249) and sodium nitrite (E 250) when used as food additives. The ADIs established by the SCF (1997) and by JECFA (2002) for nitrite were 0-0.06 and 0-0.07 mg/kg bw per day, respectively. The available information did not indicate in vivo genotoxic potential for sodium and potassium nitrite. Overall, an ADI for nitrite per se could be derived from the available repeated dose toxicity studies in animals, also considering the negative carcinogenicity results. The Panel concluded that an increased methaemoglobin level, observed in human and animals, was a relevant effect for the derivation of the ADI. The Panel, using a BMD approach, derived an ADI of 0.07 mg nitrite ion/kg bw per day. The exposure to nitrite resulting from its use as food additive did not exceed this ADI for the general population, except for a slight exceedance in children at the highest percentile. The Panel assessed the endogenous formation of nitrosamines from nitrites based on the theoretical calculation of the NDMA produced upon ingestion of nitrites at the ADI and estimated a MoE > 10,000. The Panel estimated the MoE to exogenous nitrosamines in meat products to be < 10,000 in all age groups at high level exposure. Based on the results of a systematic review, it was not possible to clearly discern nitrosamines produced from the nitrite added at the authorised levels, from those found in the food matrix without addition of external nitrite. In epidemiological studies there was some evidence to link (i) dietary nitrite and gastric cancers and (ii) the combination of nitrite plus nitrate from processed meat and colorectal cancers. There was evidence to link preformed NDMA and colorectal cancers.

High Salt Intake Is Associated with Atrophic Gastritis with Intestinal Metaplasia

Background: Although several studies have investigated excessive salt intake as a risk factor for gastric precancerous lesions, such as atrophic gastritis and intestinal metaplasia, the evidence is insufficient to make a conclusion. We evaluated the association between gastric precancerous lesions and salt intake.Methods: From 2008 to 2015, the medical records of 728 subjects who underwent upper gastrointestinal endoscopy and sodium excretion in 24-hour urine tests were retrospectively reviewed. Sixty-six subjects were excluded due to diuretics use (n = 55), diagnosis with a gastric neoplasm (n = 4), or the cases of intestinal metaplasia in the absence of atrophy (n = 7), so 662 subjects were included. Atrophic gastritis and intestinal metaplasia were diagnosed by endoscopic findings. The subjects were grouped into three levels by tertiles of 24-hour urine sodium excretion.Results: A total of 192 (29.0%) had atrophic gastritis without intestinal metaplasia and 112 (16.9%) had atrophic gastritis with intestinal metaplasia. A total of 276 subjects (61.5%) were infected with Helicobacter pylori (H. pylori). In multivariate analyses, H. pylori infection [OR = 14.17; 95% confidence interval (CI), 7.12-28.22) was associated with atrophic gastritis without intestinal metaplasia. Highest levels of sodium excretion (OR = 2.870; 95% CI, 1.34-6.14), heavy smoking (≥20 pack-years) (OR = 2.75; 95% CI, 1.02-7.39), and H. pylori infection (OR = 3.96; 95% CI, 2.02-7.76) were associated with atrophic gastritis with intestinal metaplasia.Conclusions: Our endoscopy-based study suggested that high salt intake could be associated with an increased risk of atrophic gastritis with intestinal metaplasia.Impact: Low salt diet might be helpful to prevent gastric carcinogenesis. Cancer Epidemiol Biomarkers Prev; 26(7); 1133-8. ©2017 AACR.

Dietary Patterns and Risk of Esophageal Cancer Mortality: The Japan Collaborative Cohort Study

Several case-control studies have associated dietary patterns with esophageal cancer (EC) risk, but prospective studies are scarce. We investigated dietary pattern and EC mortality risk associations by smoking status. Participants were 26,562 40- to 79-yr-old Japanese men, who enrolled in the Japan Collaborative Cohort Study between 1988 and 1990. Hazard ratios (HRs) and 95% confidence intervals (CIs) for EC mortality in nonsmokers and smokers were estimated using Cox proportional models. During follow-up (1988-2009), 132 participants died of EC. Using a baseline food frequency questionnaire and factor analysis, vegetable, animal, and dairy product food patterns were identified. EC risk decreased significantly with a higher factor score for the dairy product pattern (Ptrend = 0.042) and was more pronounced in smokers [multivariable HR (4th vs. 1st quartiles) = 0.57, 95% CI: 0.30, 1.09; Ptrend = 0.021]. Neither vegetable nor animal food patterns were significant overall; however, EC risk increased with a higher factor score for the animal food pattern in nonsmokers [multivariable HR (4th vs. 1st quartiles) = 6.01, 95% CI: 1.17, 30.88; Ptrend = 0.021], although the small number of events was a limitation. Our findings suggest a dairy product pattern may reduce EC risk in Japanese men, especially smokers.

Diet, nutrition, and cancer: past, present and future

Despite the potentially important roles of diet and nutrition in cancer prevention, the evidence to support these roles is widely perceived by the public and health professionals as being inconsistent. In this Review, we present the issues and challenges in conducting and interpreting diet-cancer research, including those relating to the design of epidemiological studies, dietary data collection methods, and factors that affect the outcome of intervention trials. Approaches to improve effect estimates, such as the use of biomarkers to improve the accuracy of characterizing dietary exposures, are also discussed. Nutritional and dietary patterns are complex; therefore, the use of a reductionist approach to investigations, by focusing on specific nutrients, can produce misleading information. The effects of tumour heterogeneity and the failure to appreciate the nonlinear, U-shaped relationship between micronutrients and cancer in both observational studies and clinical trials are discussed. New technologies and investigational approaches are enabling the exploration of complex interactions between genetic, epigenetic, metabolic, and gut-microbial processes that will inform our knowledge of the diet-cancer relationship. Communicating the status of the evolving science in the context of the overall scientific evidence base, and evidence-based dietary recommendations for cancer prevention, should be emphasized in guidance for the public and for individual patients.

Which modifiable health risk behaviours are related? A systematic review of the clustering of Smoking, Nutrition, Alcohol and Physical activity ('SNAP') health risk factors

OBJECTIVE

There is a growing body of literature examining the clustering of health risk behaviours, but little consensus about which risk factors can be expected to cluster for which sub groups of people. This systematic review aimed to examine the international literature on the clustering of smoking, poor nutrition, excess alcohol and physical inactivity (SNAP) health behaviours among adults, including associated socio-demographic variables.

METHOD

A literature search was conducted in May 2014. Studies examining at least two SNAP risk factors, and using a cluster or factor analysis technique, or comparing observed to expected prevalence of risk factor combinations, were included.

RESULTS

Fifty-six relevant studies were identified. A majority of studies (81%) reported a 'healthy' cluster characterised by the absence of any SNAP risk factors. More than half of the studies reported a clustering of alcohol with smoking, and half reported clustering of all four SNAP risk factors. The methodological quality of included studies was generally weak to moderate. Males and those with greater social disadvantage showed riskier patterns of behaviours; younger age was less clearly associated with riskier behaviours.

CONCLUSION

Clustering patterns reported here reinforce the need for health promotion interventions to target multiple behaviours, and for such efforts to be specifically designed and accessible for males and those who are socially disadvantaged.

Dietary Nitrates, Nitrites, and Nitrosamines Intake and the Risk of Gastric Cancer: A Meta-Analysis

The potential associations between dietary consumption of nitrates, nitrites, and nitrosamines and gastric cancer risk have been investigated by several studies, but yielded inconclusive results. We conducted a meta-analysis to provide a quantitative assessment of their relationships. Relevant articles were identified by a systematic literature searching of PubMed and Embase databases prior to August 2015. Random-effects models were employed to pool the relative risks. A total of 22 articles consisting of 49 studies-19 studies for nitrates, 19 studies for nitrites, and 11 studies for N-nitrosodimethylamine (NDMA)-were included. The summary relative risk of stomach cancer for the highest categories, compared with the lowest, was 0.80 (95% confidence interval (CI), 0.69-0.93) for dietary nitrates intake, 1.31 (95% CI, 1.13-1.52) for nitrites, and 1.34 (95% CI, 1.02-1.76) for NDMA (p for heterogeneity was 0.015, 0.013 and <0.001, respectively). The study type was found as the main source of heterogeneity for nitrates and nitrites. The heterogeneity for NDMA could not be eliminated completely through stratified analysis. Although significant associations were all observed in case-control studies, the cohort studies still showed a slight trend. The dose-response analysis indicated similar results as well. High nitrates intake was associated with a weak but statistically significant reduced risk of gastric cancer. Whereas increased consumption of nitrites and NDMA seemed to be risk factors for cancer. Due to the lack of uniformity for exposure assessment across studies, further prospective researches are warranted to verify these findings.

Dietary patterns and the risk of esophageal squamous cell carcinoma: A population-based case-control study in a rural population

BACKGROUND & AIMS

Few studies were available in exploring the roles of dietary patterns in the development of esophageal cancer, especially in China. This study aimed to investigate the roles of dietary patterns in the risk of esophageal squamous cell carcinoma (ESCC) in a Chinese rural population.

METHODS

A population-based cases-control study was designed and conducted in Yanting County, Sichuan Province of China during two years (between June 2011 and May 2013). A total of 942 pairs of ESCC cases and controls were recruited. A food frequency questionnaire was adopted to collect information of dietary consumption. Dietary patterns were extracted by using principle component and factor analysis based on 24 dietary groups. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated by using logistic regression model, with adjustment for possible confounding variables.

RESULTS

Four major dietary patterns were identified, which were labeled as "prudent", "vegetable and fruits", "processed food" and "alcohol drinking". In comparison of the highest with the lowest quartiles of pattern scores, the processed food pattern (OR: 2.84, 95% CI: 2.13-3.80) and alcohol drinking pattern (OR: 2.69, 95% CI: 1.95-3.71) were significantly associated with an increased risk of ESCC, while the vegetable and fruit pattern (OR: 0.70, 95% CI: 0.53-0.92) was associated with reduced risk by 30%. The prudent pattern was associated with a reduced risk by 33% (OR: 0.67, 95% CI: 0.50-0.88) in a multivariate logistic regression model, but no statistical significance was reached in a composite model.

CONCLUSIONS

The results suggest an important role of dietary patterns in ESCC. Diets rich in vegetables and fruits may decrease the risk of ESCC, whereas diets rich in processed food and drinking alcohol may increase the risk.

Lifestyle Patterns Are Associated with Elevated Blood Pressure among Qatari Women of Reproductive Age: A Cross-Sectional National Study

Women of childbearing age are particularly vulnerable to the adverse effects of elevated blood pressure (BP), with dietary and lifestyle habits being increasingly recognized as important modifiable environmental risk factors for this condition. Using data from the National STEPwise survey conducted in Qatar in year 2012, we aimed to examine lifestyle patterns and their association with elevated BP among Qatari women of childbearing age (18–45 years). Socio-demographic, lifestyle, dietary, anthropometric and BP data were used (n = 747). Principal component factor analysis was applied to identify the patterns using the frequency of consumption of 13 foods/food groups, physical activity level, and smoking status. Multivariate logistic regression analyses were used to evaluate the association of the identified lifestyle patterns with elevated BP and to examine the socio-demographic correlates of these patterns. Three lifestyle patterns were identified: a “healthy” pattern characterized by intake of fruits, natural juices, and vegetables; a “fast food & smoking” pattern characterized by fast foods, sweetened beverages, and sweets, in addition to smoking; and a “traditional sedentary” pattern which consisted of refined grains, dairy products, and meat in addition to low physical activity. The fast food & smoking and the traditional & sedentary patterns were associated with an approximately 2-fold increase in the risk of elevated BP in the study population. The findings of this study highlight the synergistic effect that diet, smoking and physical inactivity may have on the risk of elevated BP among Qatari women.

Diet and upper gastrointestinal malignancies

Diet is believed to modulate cancer risk and this relationship has been widely studied in the gastrointestinal tract. Observational epidemiologic studies have provided most of the evidence about the effects of diet on cancer risk because clinical trials to determine nutritional exposures are often impossible, impractical, or unaffordable. Although a few foods or nutrients are thought to protect against specific types of cancer, it seems clear that the strength and even direction of dietary associations (increasing or decreasing risk) is organ-site- and even histology-specific, along the gastrointestinal tract. Although some hypotheses are supported by a substantial body of observational data (drinking hot maté [an infusion of the herb Ilex Paraguarensis] contributes to esophageal cancer), there are not much data to support others. We discuss some highly touted hypotheses and draw interim conclusions about what is known and what could be done to improve the level of evidence. The complex nature of diet and its associations can be productively investigated with disease-specific studies. However, public health recommendations for normal-risk individuals regarding diet and gastrointestinal cancer should probably emphasize the importance of eating for overall health rather than eating specific foods to reduce risk for specific cancers.

Dietary habits and esophageal cancer

Cancer of the esophagus is an underestimated, poorly understood, and changing disease. Its overall 5-year survival is less than 20%, even in the United States, which is largely a function of a delay in diagnosis until its more advanced stages. Additionally, the epidemiologic complexities of esophageal cancer are vast, rendering screening and prevention limited at best. First, the prevalence of esophageal cancer is unevenly distributed throughout the world. Second, the two histological forms (squamous cell and adenocarcinoma) vary in terms of their geographic prevalence and associated risk factors. Third, some populations appear at particular risk for esophageal cancer. And fourth, the incidence of esophageal cancer is in continuous flux among groups. Despite the varied prevalence and risks among populations, some factors have emerged as consistent associations while others are only now becoming more fully recognized. The most prominent, scientifically supported, and long-regarded risk factors for esophageal cancer are tobacco, alcohol, and reflux esophagitis. Inasmuch as the above are regarded as important risk factors for esophageal cancer, they are not the sole contributors. Dietary habits, nutrition, local customs, and the environment may be contributory. Along these lines, vitamins, minerals, fruits, vegetables, meats, fats, salted foods, nitrogen compounds, carcinogens, mycotoxins, and even the temperature of what we consume are increasingly regarded as potential etiologies for this deadly although potentially preventable disease. The goal of this review is to shed light on the less known role of nutrition and dietary habits in esophageal cancer.

Pathophysiological mechanisms linking obesity and esophageal adenocarcinoma

In recent decades there has been a dramatic rise in the incidence of esophageal adenocarcinoma (EAC) in the developed world. Over approximately the same period there has also been an increase in the prevalence of obesity. Obesity, especially visceral obesity, is an important independent risk factor for the development of gastro-esophageal reflux disease, Barrett’s esophagus and EAC. Although the simplest explanation is that this mediated by the mechanical effects of abdominal obesity promoting gastro-esophageal reflux, the epidemiological data suggest that the EAC-promoting effects are independent of reflux. Several, not mutually exclusive, mechanisms have been implicated, which may have different effects at various points along the reflux-Barrett’s-cancer pathway. These mechanisms include a reduction in the prevalence of Helicobacter pylori infection enhancing gastric acidity and possibly appetite by increasing gastric ghrelin secretion, induction of both low-grade systemic inflammation by factors secreted by adipose tissue and the metabolic syndrome with insulin-resistance. Obesity is associated with enhanced secretion of leptin and decreased secretion of adiponectin from adipose tissue and both increased leptin and decreased adiponectin have been shown to be independent risk factors for progression to EAC. Leptin and adiponectin have a set of mutually antagonistic actions on Barrett’s cells which appear to influence the progression of malignant behaviour. At present no drugs are of proven benefit to prevent obesity associated EAC. Roux-en-Y reconstruction is the preferred bariatric surgical option for weight loss in patients with reflux. Statins and aspirin may have chemopreventative effects and are indicated for their circulatory benefits.

The role of obesity in oesophageal cancer development

The incidence of oesophageal adenocarcinoma has increased dramatically in the developed world in the last half century. Over approximately the same period there has been an increase in the prevalence of obesity. Multiple epidemiological studies and meta-analyses have confirmed that obesity, especially abdominal, visceral obesity, is a risk factor for gastro-oesophageal reflux, Barrett's oesophagus and oesophageal adenocarcinoma. Although visceral obesity enhances gastro-oesophageal reflux, the available data also show that visceral obesity increases the risk of Barrett's oesophagus and adenocarcinoma via reflux-independent mechanisms. Several possible mechanisms could link obesity with the risk of oesophageal adenocarcinoma in addition to mechanical effects increasing reflux. These include reduced gastric Helicobacter pylori infection, altered intestinal microbiome, factors related to lifestyle, the metabolic syndrome and associated low-grade inflammation induced by obesity and the secretion of mediators by adipocytes which may directly influence the oesophageal epithelium. Of these adipocyte-derived mediators, increased leptin levels have been independently associated with progression to oesophageal adenocarcinoma and in laboratory studies leptin enhances malignant behaviours in cell lines. Adiponectin is also secreted by adipocytes and levels decline with obesity: decreased serum adiponectin levels are associated with malignant progression in Barrett's oesophagus and experimentally adiponectin exerts anticancer effects in Barrett's cell lines and inhibits growth factor signalling. At present there are no proven chemopreventative interventions that may reduce the incidence of obesity-associated oesophageal cancer: observational studies suggest that the combined use of a statin and aspirin or another cyclo-oxygenase inhibitor is associated with a significantly reduced cancer incidence in patients with Barrett's oesophagus.

Identification of microRNAs as potential biomarker for gastric cancer by system biological analysis

Gastric cancers (GC) have the high morbidity and mortality rates worldwide and there is a need to identify sufficiently sensitive biomarkers for GC. MicroRNAs (miRNAs) could be promising potential biomarkers for GC diagnosis. We employed a systematic and integrative bioinformatics framework to identify GC-related microRNAs from the public microRNA and mRNA expression dataset generated by RNA-seq technology. The performance of the 17 candidate miRNAs was evaluated by hierarchal clustering, ROC analysis, and literature mining. Fourteen have been found to be associated with GC and three microRNAs (miR-211, let-7b, and miR-708) were for the first time reported to associate with GC and may be used for diagnostic biomarkers for GC.

rs744166 polymorphism of the STAT3 gene is associated with risk of gastric cancer in a Chinese population

The aim of this study was to explore the association between polymorphisms in signal transducer and activator of transcription protein 3 (STAT3) and the risk of gastric cancer. In the present study, a case-control study was conducted in which rs2293152 and rs744166 polymorphisms in STAT3 were analyzed in 209 Chinese patients with gastric cancer and 294 cancer-free controls. The genotypes were determined by polymerase chain reaction restriction fragment length polymorphism method. For the rs744166 polymorphism, the TC genotype (adjusted OR = 0.60, 95% CI = 0.39-0.92, and P = 0.020) and CC genotype (adjusted OR = 0.41, 95% CI = 0.21-0.80, and P = 0.009) were associated with a decreased risk of gastric cancer compared to the TT genotype. However, rs2293152 did not show any difference in gastric cancer risk between patients and controls in the CG/CC genotype compared to the GG genotype. Besides, the SNP effects were additive to the effects of environmental factors without any interaction between them in the susceptibility to gastric cancer. Collectively, rs744166 polymorphism might be significantly associated with a decreased risk of gastric cancer in a Chinese population. Additionally, polymorphisms in STAT3, along with environmental factors, might be associated with the development of gastric cancer.

Dietary patterns and oesophageal squamous cell carcinoma: a systematic review and meta-analysis

Background/Objective:

Dietary patterns, which represent a complex integration of food and nutrients, have been used to explore the association between dietary factors and the risk of oesophageal cancer. However, the association remains unclear. This systematic review was performed to evaluate the relationship between dietary patterns and oesophageal squamous cell carcinoma (ESCC) by pooling available data from existing studies.

Methods:

Pertinent articles published up to the end of 2013 were systematically searched and retrieved. The most common dietary patterns with high loadings of foods/nutrients were selected. Adjusted odds ratios (ORs) were derived by comparing the highest with the lowest categories of dietary pattern scores and by using a random-effect model. Heterogeneity was tested using I² statistic.

Results:

From nine available case–control studies, in which smoking and other confounding factors were considered, three most common dietary patterns were selected: western pattern, healthy pattern, and drinker/alcohol pattern. Healthy pattern was significantly associated with a decreased risk of ESCC (OR=0.36, 95% confidence interval (CI): 0.23, 0.49); drinker/alcohol pattern was related to a significantly increased risk (OR=2.34, 95% CI: 1.22, 3.45), while no significant association with western pattern was observed (OR=1.29, 95% CI: 0.83, 1.75).

Conclusions:

Based on available studies, though limited in number, this meta-analysis suggests that some dietary patterns may be associated with the risk of ESCC.

Meat consumption is associated with esophageal cancer risk in a meat- and cancer-histological-type dependent manner

BACKGROUND

We conducted a systematic review and meta-analysis of meat intake and esophageal cancer risk, with subgroup analyses based on meat type and histological type of cancer.

AIMS

The purpose of this study was to investigate the association between meat intake and risk of esophageal cancer.

METHODS

We searched MEDLINE, EMBASE and Cochrane Library (April 2013) for cohort and case-control studies that assessed meat intake and esophageal cancer risk. Random-effect or fixed-effect models were used to pool relative risks (RRs) from individual studies with heterogeneity and publication bias analyses carried out. Seven cohort and 28 case-control studies were included.

RESULTS

The summary RRs for esophageal cancer for the highest versus lowest consumption categories were 1.19 (95 % confidence interval [CI] 0.98-1.46) for total meat, 1.55 (95 % CI 1.22-1.96) for red meat, 1.33 (95 % CI 1.04-1.69) for processed meat, 0.72 (95 % CI 0.60-0.86) for white meat, 0.83 (95 % CI 0.72-0.96) for poultry, and 0.95 (95 % CI 0.76-1.19) for fish. When striated by histological subtype, positive associations were seen among esophageal squamous cell carcinoma and red meat, white meat and poultry, and esophageal adenocarcinoma with total meat and processed meat.

CONCLUSIONS

Meat consumption is associated with esophageal cancer risk, which depends on meat type and histological type of esophageal cancer. High intake of red meat and low intake of poultry are associated with an increased risk of esophageal squamous cell carcinoma. High meat intake, especially processed meat, is likely to increase esophageal adenocarcinoma risk. And fish consumption may not be associated with incidence of esophageal cancer.

Diet and lifestyle factors and risk of subtypes of esophageal and gastric cancers: classification tree analysis

PURPOSE

Although risk factors for squamous cell carcinoma of the esophagus and adenocarcinomas of the esophagus (EA), gastric cardia (GC), and other (noncardia) gastric (OG) sites have been identified, little is known about interactions among risk factors. We sought to examine interactions of diet, other lifestyle, and medical factors with risks of subtypes of esophageal and gastric cancers.

METHODS

We used classification tree analysis to analyze data from a population-based case-control study (1095 cases, 687 controls) conducted in Connecticut, New Jersey, and western Washington State.

RESULTS

Frequency of reported gastroesophageal reflux disease symptoms was the most important risk stratification factor for EA, GC, and OG, with dietary factors (EA, OG), smoking (EA, GC), wine intake (GC, OG), age (OG), and income (OG) appearing to modify the risk of these cancer sites. For esophageal squamous cell carcinoma, smoking was the most important risk stratification factor, with gastroesophageal reflux disease, income, race, noncitrus fruit, and energy intakes further modifying risk.

CONCLUSION

Various combinations of risk factors appear to interact to affect risk of each cancer subtype. Replication of these data mining analyses are required before suggesting causal pathways; however, the classification tree results are useful in partitioning risk and mapping multilevel interactions among risk variables.

Dietary patterns and stomach cancer: a meta-analysis

Investigation of the relationship between dietary patterns and some chronic diseases becomes appealing in nutrition epidemiology. Many studies reported potential associations between different dietary patterns and the risk of stomach cancer, however, a consistent perspective hasn't been established to date. Herein, we carried this meta-analysis to identify the associations between different dietary patterns and the risk of stomach cancer. A total of 23 studies met the inclusion criteria and were included in this meta-analysis. A decreased risk of stomach cancer was shown for the highest compared with the lowest category of a "healthy" dietary pattern [odds ratio (OR) = 0.69; confidence interval (CI): 0.53, 0.89; P = 0.005). There were evidence of the increased risk of stomach cancer in the highest compared with the lowest categories of Western-style pattern (OR = 1.59; CI: 1.25, 2.04; P = 0.0002) and alcohol-drinking pattern (OR = 1.37; CI: 1.11, 1.70; P = 0.004). The results of this meta-analysis indicate that healthy dietary pattern may decrease the risk of stomach cancer, whereas Western-style and alcohol-drinking dietary patterns may increase the risk of stomach cancer.

Index-based dietary patterns and risk of esophageal and gastric cancer in a large cohort study

BACKGROUND & AIMS

Diet could affect risk for esophageal and gastric cancers, but associations have been inconsistent. The diet is complex, so studies of dietary patterns, rather than studies of individual foods, might be more likely to identify cancer risk factors. There is limited research on index-based dietary patterns and esophageal and gastric cancers. We prospectively evaluated associations between the Healthy Eating Index-2005 (HEI-2005) and alternate Mediterranean Diet (aMED) scores and risk of esophageal and gastric cancers.

METHODS

We analyzed data from 494,968 participants in the National Institutes of Health-AARP Diet and Health study, in which AARP members (age, 51-70 y) completed a self-administered baseline food frequency questionnaire between 1995 and 1996. Their answers were used to estimate scores for each index.

RESULTS

During the follow-up period (1995-2006), participants developed 215 esophageal squamous cell carcinomas (ESCCs), 633 esophageal adenocarcinomas (EACs), 453 gastric cardia adenocarcinomas, and 501 gastric noncardia adenocarcinomas. Higher scores from the HEI-2005 were associated with a reduced risk of ESCC (comparing the highest quintile with the lowest quintile: hazard ratio, 0.51; 95% confidence interval, 0.31-0.86; Ptrend = .001) and EAC (hazard ratio, 0.75; 95% confidence interval, 0.57-0.98; Ptrend = .01). We observed an inverse association between ESCC, but not EAC, and a higher aMED score (meaning a higher-quality diet). HEI-2005 and aMED scores were not associated significantly with gastric cardia or noncardia adenocarcinomas.

CONCLUSIONS

By using data collected from 1995 through 2006 from the National Institutes of Health-AARP Diet and Health Study, HEI-2005 and aMED scores were associated inversely with risk for esophageal cancers, particularly ESCC. Adherence to dietary recommendations might help prevent esophageal cancers.

A scoping review of statistical approaches to the analysis of multiple health-related behaviours

BACKGROUND

Smoking, diet, exercise, and alcohol are leading causes of chronic disease and premature death, many engage in two or more of these behaviours concurrently. The paper identified statistical approaches used to investigate multiple behavioural risk factors.

METHOD

A scoping review of papers published in English from 2000 to 2011 was conducted; papers are related to concurrent participation in at least two of the behaviours. Statistical approaches were recorded and categorised.

RESULTS

Across 50 papers, two distinct approaches were identified. Co-occurrence analyses focused on concurrent but independent behaviours, represented by prevalence of behavioural combinations and/or by the summing behaviours into risk indexes. Clustering analyses investigated underlying associations between the concurrent behaviours, with clustering identified by divergences in observed and expected prevalence of combinations or through identification of latent or unobservable clusters. Co-occurrence was more frequently reported, but the use of clustering techniques and, in particular, cluster analytic and latent variable techniques increased across the study period.

DISCUSSION

The two approaches investigate concurrent participation in multiple health behaviours but differ in conceptualisation and analysis. Despite differences, inconsistency in the terminology describing the study of multiple health behaviours was apparent, with potential to influence understandings of concurrent health behaviours in policy and practice.