[show abstract][hide abstract] ABSTRACT: Gastric cancer affects about one million people per year worldwide, being the second leading cause of cancer mortality. The study of its etiology remains therefore a global issue as it may allow the identification of major targets, besides eradication of Helicobacter pylori infection, for primary prevention. It has however received little attention, given its comparatively low incidence in most high-income countries. We introduce a consortium of epidemiological investigations named the 'Stomach cancer Pooling (StoP) Project'. Twenty-two studies agreed to participate, for a total of over 9000 cases and 23 000 controls. Twenty studies have already shared the original data set. Of the patients, 40% are from Asia, 43% from Europe, and 17% from North America; 34% are women and 66% men; the median age is 61 years; 56% are from population-based case-control studies, 41% from hospital-based ones, and 3% from nested case-control studies derived from cohort investigations. Biological samples are available from 12 studies. The aim of the StoP Project is to analyze the role of lifestyle and genetic determinants in the etiology of gastric cancer through pooled analyses of individual-level data. The uniquely large data set will allow us to define and quantify the main effects of each risk factor of interest, including a number of infrequent habits, and to adequately address associations in subgroups of the population, as well as interaction within and between environmental and genetic factors. Further, we will carry out separate analyses according to different histotypes and subsites of gastric cancer, to identify potential different risk patterns and etiological characteristics.
European journal of cancer prevention: the official journal of the European Cancer Prevention Organisation (ECP) 02/2014; · 2.21 Impact Factor
[show abstract][hide abstract] ABSTRACT: The time to first cigarette (TTFC) of the day is an indicator of nicotine intake in adults and adolescents. However, the relation between TTFC and biological markers of nicotine addiction and health risk in youths has not been well described. The current study examined whether an earlier TTFC predicts higher levels of a tobacco-specific carcinogen, 4-(methylnitrosamino)-1-(3-pyridal)-1 (NNAL), in regular and intermittent adolescent smokers and if this relation is mediated by nicotine intake (measured by cotinine) or cigarettes per day (CPD).
A cross-sectional analysis of a nationally representative subsample of adolescents.
A general community sample from the 2007-2008 and 2009-2010 National Health and Nutrition and Examination Survey.
215 adolescents in the United States between the ages of 12 and 19 who reported smoking at least once in the 5 days prior to data collection.
The primary outcome measure was urinary levels of NNAL.
In both regular and intermittent smokers, earlier TTFC was dose-dependently associated with higher levels of NNAL (p's < 0.03 in both cases). TTFC had an indirect effect on NNAL, mediated by nicotine intake (cotinine) in both regular (β = -.08, SE = .03, 95% CI [-.15, -.04]), and intermittent (β = -.02, SE = .01, 95% CI [-.05, -.002]) smokers. CPD was not found to be an important mediator of the relation between TTFC and NNAL.
Time between waking and the first cigarette of the day is correlated in daily and non-daily adolescent smokers with overall nicotine and therefore carcinogen intake.
[show abstract][hide abstract] ABSTRACT: A microarray (LungCaGxE), based on Illumina BeadChip technology, was developed for high-resolution genotyping of genes that are candidates for involvement in environmentally driven aspects of lung cancer oncogenesis and/or tumor growth. The iterative array design process illustrates techniques for managing large panels of candidate genes and optimizing marker selection, aided by a new bioinformatics pipeline component, Tagger Batch Assistant. The LungCaGxE platform targets 298 genes and the proximal genetic regions in which they are located, using ∼13,000 DNA single nucleotide polymorphisms (SNPs), which include haplotype linkage markers with a minimum allele frequency of 1% and additional specifically targeted SNPs, for which published reports have indicated functional consequences or associations with lung cancer or other smoking-related diseases. The overall assay conversion rate was 98.9%; 99.0% of markers with a minimum Illumina design score of 0.6 successfully generated allele calls using genomic DNA from a study population of 1873 lung-cancer patients and controls.
Journal of biomolecular techniques: JBT 12/2013; 24(4):198-217.
[show abstract][hide abstract] ABSTRACT: Several epidemiological studies have shown a positive association between adult height and cancer incidence. The only study conducted among women on mouth and pharynx cancer risk, however, reported an inverse association. This study aims to investigate the association between height and the risk of head and neck cancer (HNC) within a large international consortium of HNC. We analyzed pooled individual-level data from 24 case-control studies participating in the International Head and Neck Cancer Epidemiology Consortium. Odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated separately for men and women for associations between height and HNC risk. Educational level, tobacco smoking, and alcohol consumption were included in all regression models. Stratified analyses by HNC subsites were performed. This project included 17,666 cases and 28,198 controls. We found an inverse association between height and HNC (adjusted OR per 10 cm height = 0.91, 95 % CI 0.86-0.95 for men; adjusted OR = 0.86, 95 % CI 0.79-0.93 for women). In men, the estimated OR did vary by educational level, smoking status, geographic area, and control source. No differences by subsites were detected. Adult height is inversely associated with HNC risk. As height can be considered a marker of childhood illness and low energy intake, the inverse association is consistent with prior studies showing that HNC occur more frequently among deprived individuals. Further studies designed to elucidate the mechanism of such association would be warranted.
European Journal of Epidemiology 11/2013; · 5.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: Cigar and pipe smoking are considered risk factors for head and neck cancers, but the magnitude of effect estimates for these products has been imprecisely estimated. By using pooled data from the International Head and Neck Cancer Epidemiology (INHANCE) Consortium (comprising 13,935 cases and 18,691 controls in 19 studies from 1981 to 2007), we applied hierarchical logistic regression to more precisely estimate odds ratios and 95% confidence intervals for cigarette, cigar, and pipe smoking separately, compared with reference groups of those who had never smoked each single product. Odds ratios for cigar and pipe smoking were stratified by ever cigarette smoking. We also considered effect estimates of smoking a single product exclusively versus never having smoked any product (reference group). Among never cigarette smokers, the odds ratio for ever cigar smoking was 2.54 (95% confidence interval (CI): 1.93, 3.34), and the odds ratio for ever pipe smoking was 2.08 (95% CI: 1.55, 2.81). These odds ratios increased with increasing frequency and duration of smoking (Ptrend ≤ 0.0001). Odds ratios for cigar and pipe smoking were not elevated among ever cigarette smokers. Head and neck cancer risk was elevated for those who reported exclusive cigar smoking (odds ratio = 3.49, 95% CI: 2.58, 4.73) or exclusive pipe smoking (odds ratio = 3.71, 95% CI: 2.59, 5.33). These results suggest that cigar and pipe smoking are independently associated with increased risk of head and neck cancers.
American journal of epidemiology 06/2013; · 5.59 Impact Factor
[show abstract][hide abstract] ABSTRACT: This study examined the relationship between the time to the first cigarette (TTFC) of the morning with quit status among adolescent smokers at the completion of a school-based smoking cessation program. Among those who did not quit, the relationship of TTFC with changes in cigarettes/day (CPD) was also examined.
A total of 1,167 adolescent smokers (1,024 nonquitters and 143 quitters) from 4 states participating in efficacy and effectiveness studies of the Not-On-Tobacco (N-O-T) cessation program were assessed prior to entry into the program and again 3 months later, at the end of treatment. Linear and logistic regression analyses determined the influence of treatment condition, age, gender, motivation to quit, confidence in quitting ability, baseline CPD, and TTFC on quit status and end-of-treatment CPD.
Adolescents with a TTFC of >30min of waking were twice as likely to quit at end of treatment. Additionally, among those who did not quit at end of treatment (n = 700 for TTFC ≤30min and n = 324 for TTFC for >30min), those with a TTFC within 30min of waking smoked a greater number of CPD. The relationships of TTFC with both of these outcomes remained when controlling for all other predictor variables.
Identifying adolescent smokers who smoke their first cigarette of the day within the first 30min of waking prior to a quit attempt may help to classify those individuals as having a greater risk for cessation failure. Thus, TTFC may be a behavioral indicator of nicotine dependence in adolescents.
Nicotine & Tobacco Research 06/2013; · 2.48 Impact Factor
[show abstract][hide abstract] ABSTRACT: We evaluated the role of dietary iron, heme iron, and supplemental iron on colorectal cancer (CRC) risk in a population-based case-control study in Pennsylvania, including 1005 incident cases and 1062 controls. Diet was assessed through a modified food frequency questionnaire that included supplement use and a meat-specific module. Cases reported intakes for the year before diagnosis, whereas controls reported intakes for the year before interview. Heme iron intake was calculated using a new heme database developed by the US National Cancer Institute. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. After multivariate adjustment, there were no significant associations between heme iron or total iron intake and CRC incidence. Dietary iron intake was inversely associated with CRC among women (OR Q5 vs. Q1=0.45; 95% CI=0.22-0.92), but not among men. Supplemental iron intake of more than 18 mg/day versus none was positively associated with CRC incidence (OR=2.31; 95% CI=1.48-3.59; P-trend<0.001), an effect that was observed in both men (OR=2.56; 95% CI=1.30-5.05) and women (OR=2.46; 95% CI=1.34-4.52). These findings suggest that consumption of more than 18 mg/day of supplemental iron may increase risk for CRC.
European journal of cancer prevention: the official journal of the European Cancer Prevention Organisation (ECP) 03/2013; · 2.21 Impact Factor
[show abstract][hide abstract] ABSTRACT: Since meat may be involved in the etiology of colorectal cancer, associations between meat-related compounds were examined to elucidate underlying mechanisms in a population-based case-control study. Participants (989 cases/1,033 healthy controls) completed a food frequency questionnaire with a meat-specific module. Multivariable logistic regression was used to examine associations between meat variables and colorectal cancer; polytomous logistic regression was used for subsite-specific analyses. The following significant positive associations were observed for meat-related compounds: 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and colorectal, distal colon, and rectal tumors; 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and colorectal and colon cancer tumors; nitrites/nitrates and proximal colon cancer; 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and rectal cancer; and benzo[a]pyrene and rectal cancer (P-trends < 0.05). For analyses by meat type, cooking method, and doneness preference, positive associations between red processed meat and proximal colon cancer and pan-fried red meat and colorectal cancer were found (P-trends < 0.05). Inverse associations were observed between unprocessed poultry and colorectal, colon, proximal colon, and rectal tumors; grilled/barbequed poultry and proximal colon cancer; and well-done/charred poultry and colorectal, colon, and proximal colon tumors (P-trends < 0.05). HCAs, PAHs, nitrites, and nitrates may be involved in colorectal cancer etiology. Further examination into the unexpected inverse associations between poultry and colorectal cancer is warranted.
Nutrition and Cancer 02/2013; 65(2):202-26. · 2.70 Impact Factor
[show abstract][hide abstract] ABSTRACT: INTRODUCTION: Nicotine dependence and uptake among adolescents remains challenging to characterize and measure. Among adults, a shorter time to the first cigarette after waking up in the morning (TTFC) has become increasingly recognized as an indicator of nicotine dependence because of its association with biological measures of nicotine exposure, smoking relapse, and failed cessation attempts. However, the relation between TTFC and these measures has not been studied among adolescents. This study explored the association between TTFC and cotinine among adolescent smokers. METHODS: The study utilized 2007-2008 and 2009-2010 National Health and Nutrition Examination Survey (NHANES) data from 220 regular adolescent smokers between the ages of 12 and 19 who provided blood samples for cotinine evaluation. Regression modeling was conducted to determine whether TTFC predicts cotinine levels, a marker of nicotine uptake. RESULTS: The time to first cigarette was significantly correlated with several smoking behaviors including number of cigarettes per day, time since last cigarette, and having a family member who smokes at home. Mean cotinine levels were more than 200ng/ml in youths who smoked within 5min after waking, compared with less than 34ng/ml in youths who waited for more than 1hr. In multiple regression models, a shorter time to first cigarette predicted higher cotinine levels after controlling for number of cigarettes per day and other factors. The TTFC was a predictor of cotinine for both male and female smokers.Conclusion:The TTFC is a strong indicator of nicotine dependence in adolescents and could be an important component in screening for high-risk smoking and the development of tailored adolescent smoking intervention programs.
Nicotine & Tobacco Research 09/2012; · 2.48 Impact Factor
[show abstract][hide abstract] ABSTRACT: To clarify the role of previous lung diseases (chronic bronchitis, emphysema, pneumonia, and tuberculosis) in the development of lung cancer, the authors conducted a pooled analysis of studies in the International Lung Cancer Consortium. Seventeen studies including 24,607 cases and 81,829 controls (noncases), mainly conducted in Europe and North America, were included (1984-2011). Using self-reported data on previous diagnoses of lung diseases, the authors derived study-specific effect estimates by means of logistic regression models or Cox proportional hazards models adjusted for age, sex, and cumulative tobacco smoking. Estimates were pooled using random-effects models. Analyses stratified by smoking status and histology were also conducted. A history of emphysema conferred a 2.44-fold increased risk of lung cancer (95% confidence interval (CI): 1.64, 3.62 (16 studies)). A history of chronic bronchitis conferred a relative risk of 1.47 (95% CI: 1.29, 1.68 (13 studies)). Tuberculosis (relative risk = 1.48, 95% CI: 1.17, 1.87 (16 studies)) and pneumonia (relative risk = 1.57, 95% CI: 1.22, 2.01 (12 studies)) were also associated with lung cancer risk. Among never smokers, elevated risks were observed for emphysema, pneumonia, and tuberculosis. These results suggest that previous lung diseases influence lung cancer risk independently of tobacco use and that these diseases are important for assessing individual risk.
American journal of epidemiology 09/2012; 176(7):573-85. · 5.59 Impact Factor
[show abstract][hide abstract] ABSTRACT: Smokers who have their first cigarette shortly after waking, an indicator of nicotine dependence, have substantially higher cotinine levels. There is controversy regarding the role of menthol in nicotine dependence. We hypothesized that menthol smokers have a shorter time to first cigarette (TTFC), and tested whether any statistical association actually reflects increased dependence by measuring nicotine uptake (e.g. cotinine) in the same group of smokers. A cross-sectional community-based study was conducted that included 495 black and white daily cigarette smokers. Results showed a trend between menthol smoking and a shorter TTFC (P < 0.04 in blacks). Menthol was not an independent predictor of cotinine or an effect modifier with TTFC on cotinine levels in blacks and whites. These results show that while menthol in tobacco is associated with an indicator of nicotine dependence in blacks, menthol was not associated with biological uptake of nicotine in black and white smokers.
Regulatory Toxicology and Pharmacology 04/2012; 63(1):166-70. · 2.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: Familial aggregation of lung cancer exists after accounting for cigarette smoking. However, the extent to which family history affects risk by smoking status, histology, relative type and ethnicity is not well described. This pooled analysis included 24 case-control studies in the International Lung Cancer Consortium. Each study collected age of onset/interview, gender, race/ethnicity, cigarette smoking, histology and first-degree family history of lung cancer. Data from 24,380 lung cancer cases and 23,305 healthy controls were analysed. Unconditional logistic regression models and generalised estimating equations were used to estimate odds ratios and 95% confidence intervals.
Individuals with a first-degree relative with lung cancer had a 1.51-fold increase in the risk of lung cancer, after adjustment for smoking and other potential confounders (95% CI: 1.39, 1.63). The association was strongest for those with a family history in a sibling, after adjustment (odds ratios (OR) = 1.82, 95% CI: 1.62, 2.05). No modifying effect by histologic type was found. Never smokers showed a lower association with positive familial history of lung cancer (OR = 1.25, 95% CI: 1.03, 1.52), slightly stronger for those with an affected sibling (OR = 1.44, 95% CI: 1.07, 1.93), after adjustment.
The occurrence of lung cancer among never smokers and similar magnitudes of the effect of family history on lung cancer risk across histological types suggests familial aggregation of lung cancer is independent of those risks associated with cigarette smoking. While the role of genetic variation in the aetiology of lung cancer remains to be fully characterised, family history assessment is immediately available and those with a positive history represent a higher risk group.
European journal of cancer (Oxford, England: 1990) 03/2012; 48(13):1957-68. · 4.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: Cigarette smoking is the major cause of laryngeal cancer. The time to first cigarette after waking in the morning is a behavior associated with several dimensions of nicotine dependence including the dose of smoke uptake. We hypothesized that a short TTFC increases the risk of laryngeal cancer.
The analysis was based on data from a hospital-based case-control study of laryngeal cancer. The current analysis included only subjects who were ever cigarette smokers, including 570 cases and 343 controls (832 whites and 81 blacks). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression adjusting for smoking history and other potential confounders. Incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute from 1975 to 2006 were analyzed for trends in laryngeal cancer.
There was a dose-response relationship between TTFC and supraglottic cancer. Compared to subjects who smoked more than 60 min after waking, the adjusted odds ratio was 1.51 (95% CI, 0.63-3.61) for 30-60 min and 3.13 (95% CI, 1.56-6.30) for 0-30 min. No association was observed between TTFC and cancer of the glottis. In blacks, the TTFC was not associated with the risk of laryngeal cancer. Trends in SEER rates were similar for cancer of the glottis and supraglottis, indicating that the site-specific differences were not affected by unknown confounders.
A nicotine dependence behavior that is associated with cigarette smoke uptake increases the risk of cancer of the supraglottis larynx, but not glottis larynx.
Cancer Causes and Control 03/2012; 23(3):497-503. · 3.20 Impact Factor