Joint associations of smoking and television viewing time on cancer and cardiovascular disease mortality

Excessive sitting time and smoking are pro‐inflammatory lifestyle factors that are associated with both cancer and cardiovascular disease (CVD) mortality. However, their joint associations have not been investigated. We examined the associations of television (TV) viewing time with cancer and CVD mortality, according to smoking status, among 7,498 non‐smokers (34% ex‐smokers) and 1,409 current‐smokers in the Australian Diabetes, Obesity and Lifestyle Study. During 117,506 person‐years (median 13.6 years) of follow‐up, there were 346 cancer and 209 CVD‐related deaths. Including an interaction between TV time and smoking status in the model significantly improved the goodness of fit for cancer (p = 0.01) but not CVD mortality (p = 0.053). In the multivariate‐adjusted model, every additional hr/d of TV time was associated with increased risk of cancer‐related (HR 1.23; 95% CI 1.08–1.40), but not CVD‐related mortality (HR 1.16; 95% CI 0.97–1.38) in current‐smokers. Elevated multivariate‐adjusted cancer mortality HRs were observed for current‐smokers watching 2 to <4 hr/d (HR 1.45; 95% CI 0.78–2.71) and ≥4 hr/d (HR 2.26; 95% CI 1.10–4.64), compared to those watching <2 hr/d. Current‐smokers watching 2 to <4 hr/d (HR 1.07; 95% CI 0.45–2.53) and ≥4 hr/d (HR 1.92; 95% CI 0.76–4.84) did not have a significantly higher risk of CVD mortality, compared to <2 hr/d. No associations were observed for non‐smokers. These findings show an association of TV, a common sedentary behavior, with cancer mortality in current‐smokers. The association with CVD mortality was less clear. Further exploration in larger data sets is warranted. Limiting TV viewing time may be of benefit in reducing cancer mortality risk in current‐smokers.     

Mortality risk in former smokers with breast cancer: Pack‐years vs. smoking status

It is unclear why successful quitting at time of breast cancer diagnosis should remove risk from a significant lifetime of smoking. Studies concluding this may be biased by how smoking is measured in many epidemiological cohorts. In the late 1990s, a randomized trial of diet and breast cancer outcomes enrolled early‐stage female breast cancer survivors diagnosed within the previous 4 years. Smoking history and key covariate measures were available at study entry for 2,953 participants. Participants were followed for an average of 7.3 years (96% response rate). There were 10.1% deaths (83% from breast cancer). At enrollment, 55.2% were never smokers, 41.2% former smokers and 4.6% current smokers. Using current smoking status in a Cox regression, there was no increased risk for former smokers for either all‐cause mortality [hazard ratio (HR) = 1.11; 95% confidence interval (CI) = 0.87–1.41; p‐value = 0.42) or breast cancer mortality. However, when we categorized on extensive lifetime exposure, former smokers with 20+ pack‐years of smoking (25.8%) had a significantly higher risk of both all‐cause (HR = 1.77; 95% CI = 1.17–2.48; p‐value = 0.0007) and breast cancer‐specific mortality (HR = 1.62; 95% CI = 1.11–2.37; p‐value = 0.01). Lifetime smoking exposure, not current status, should be used to assess mortality risk among former smokers.     

Evaluating interactions of polygenic risk scores and NAT2 genotypes with tobacco smoking in bladder cancer risk

Tobacco smoking is the most important risk factor for bladder cancer. Previous studies have identified the N-acetyltransferase (NAT2) gene in association with bladder cancer risk. The NAT2 gene encodes an enzyme that metabolizes aromatic amines, carcinogens commonly found in tobacco smoke. In our study, we evaluated potential interactions of tobacco smoking with NAT2 genotypes and polygenic risk score (PRS) for bladder cancer, using data from the UK Biobank, a large prospective cohort study. We used Cox proportional hazards models to measure the strength of the association. The PRS was derived using genetic risk variants identified by genome-wide association studies for bladder cancer. With an average of 10.1 years of follow-up of 390 678 eligible participants of European descent, 769 incident bladder cancer cases were identified. Current smokers with a PRS in the highest tertile had a higher risk of developing bladder cancer (HR: 6.45, 95% CI: 4.51-9.24) than current smokers with a PRS in the lowest tertile (HR: 2.41, 95% CI: 1.52-3.84; P for additive interaction = <.001). A similar interaction was found for genetically predicted metabolizing NAT2 phenotype and tobacco smoking where current smokers with the slow NAT2 phenotype had an increased risk of developing bladder cancer (HR: 5.70, 95% CI: 2.64-12.30) than current smokers with the fast NAT2 phenotype (HR: 3.61, 95% CI: 1.14-11.37; P for additive interaction = .100). Our study provides support for considering both genetic and lifestyle risk factors in developing prevention measures for bladder cancer.     

Prediagnosis and postdiagnosis smoking and survival following diagnosis with ovarian cancer

Little is known about the influence of prediagnosis and postdiagnosis smoking and smoking cessation on ovarian cancer survival. We investigated this relationship in two prospective cohort studies, the Nurses’ Health Study (NHS) and NHSII. Analyses included 1,279 women with confirmed invasive, Stage I–III epithelial ovarian cancer. We used Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for ovarian cancer-specific mortality by smoking status, adjusting for age and year of diagnosis, tumor stage, histologic subtype, body mass index and nonsteroidal anti-inflammatory use (postdiagnosis models only). When examining prediagnosis smoking status (assessed a median of 12 months before diagnosis), risk of death was significantly increased for former smokers (HR = 1.19, 95% CI: 1.02–1.39), and suggestively for current smokers (HR = 1.21, 95% CI: 0.96–1.51) vs. never smokers. Longer smoking duration (≥20 years vs. never, HR = 1.23, 95% CI: 1.05–1.45) and higher pack-years (≥20 pack-years vs. never, HR = 1.28, 95% CI: 1.07–1.52) were also associated with worse outcome. With respect to postdiagnosis exposure, women who smoked ≥15 cigarettes per day after diagnosis (assessed a median of 11 months after diagnosis) had increased mortality compared to never smokers (HR = 2.34, 95% CI: 1.63–3.37). Those who continued smoking after diagnosis had 40% higher mortality (HR = 1.40, 95% CI: 1.05–1.87) compared to never smokers. Overall, our results suggest both prediagnosis and postdiagnosis smoking are associated with worse ovarian cancer outcomes.     

Passive smoking and lung cancer in Japanese non-smoking women: a prospective study

Although smoking is a major cause of lung cancer, the proportion of lung cancer cases among Japanese women who never smoked is high. As the prevalence of smoking in Japan is relatively high in men but low in women, the development of lung cancer in non-smoking Japanese women may be significantly impacted by passive smoking. We conducted a population-based prospective study established in 1990 for Cohort I and in 1993 for Cohort II. The study population was defined as all residents aged 40-69 years at the baseline survey. 28,414 lifelong non-smoking women provided baseline information on exposure to tobacco smoke from their husband, at the workplace and during childhood. Over 13 years of follow-up, 109 women were newly diagnosed with lung cancer, of whom 82 developed adenocarcinoma. Compared with women married to never smokers, hazard ratio (HR) [95% confidence interval (CI)] for all lung cancer incidence in women who lived with a smoking husband was 1.34 (95% CI 0.81-2.21). An association was clearly identified for adenocarcinoma (HR 2.03, 95% CI 1.07-3.86), for which dose-response relationships were seen for both the intensity (p for trend = 0.02) and amount (p for trend = 0.03) of the husband's smoking. Passive smoking at the workplace also increased the risk of lung cancer (HR 1.32, 95% CI 0.85-2.04). Moreover, a higher risk of adenocarcinoma was seen for combined husband and workplace exposure (HR 1.93, 95% CI 0.88-4.23). These findings confirm that passive smoking is a risk factor for lung cancer, especially for adenocarcinoma among Japanese women.     

Risk of endometrial cancer in relationship to cigarette smoking: results from the EPIC study

Current epidemiologic evidence indicates that cigarette smoking reduces the risk of endometrial cancer. We examined data from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to analyze further aspects of the smoking-endometrial cancer relationship, such as possible modifying effects of menopausal status, HRT use, BMI and parity. In a total of 249,986 women with smoking exposure and menopausal status information, 619 incident endometrial cancer cases were identified during 1.56 million person-years of follow-up. Among postmenopausal women, the hazard ratio (HR) for current smokers versus never smokers was 0.70 (95% CI = 0.53-0.93), while it was 1.75 (95% CI = 1.13-2.70) among premenopausal women at recruitment. After adjustment for risk factors, the HR for postmenopausal women was slightly attenuated to 0.78 (95% CI = 0.59-1.03). No heterogeneity of effect was observed with HRT use or BMI. Among premenopausal women, current smokers of more than 15 cigarettes per day or who smoked for 30 years or more at the time of recruitment had a more than 2-fold increased risk of endometrial cancer compared to never smokers (HR = 2.54; 95% CI = 1.47-4.38 and HR = 2.23; 95% CI = 1.04-4.77, respectively). Past smoking was not associated with endometrial cancer risk, either among pre- or postmenopausal women. In this prospective study, we observed an increased risk of endometrial cancer with cigarette smoking in premenopausal women. The reduction of endometrial cancer risk observed among postmenopausal women does not have direct public health relevance since cigarette smoking is the main known risk factor for cancer.     

A prospective study on active and environmental tobacco smoking and bladder cancer risk (The Netherlands)

Objective: In a prospective cohort study among 120,852 adult subjects the authors investigated the associations between cigarette, cigar, pipe, environmental tobacco smoking (ETS), and bladder cancer. Methods: In 1986 all subjects completed a questionnaire on cancer risk factors. Follow-up for incident bladder cancer was established by linkage to cancer registries until 1992. The case–cohort analysis was based on 619 cases and 3346 subcohort members. Results: Compared with lifelong non-smokers the age- and sex-adjusted incidence rate ratios (RR) for ex- and current cigarette smokers were 2.1 (95% CI 1.5–3.0) and 3.3 (95% CI 2.4–4.6), respectively. The RR for smoking duration was 1.03 (95% CI: 1.02–1.04) per 1-year increment. The RR per 10 cigarettes/day was 1.3 (95% CI 1.2–1.4). Tar and nicotine exposure increased bladder cancer risk only weakly. It appeared that associations of cigarette smoking characteristics with bladder cancer risk were largely attributable to cigarette smoking duration only. Smoking cessation, age at first exposure, filter-tip usage, cigar and pipe smoking, and ETS were no longer associated with bladder cancer risk after adjustment for frequency and duration of smoking. Conclusions: The authors conclude that current cigarette smokers have a three-fold higher bladder cancer risk than non-smokers. Ex-smokers experience a two-fold increased risk. About half of male bladder cancer and one-fifth of female bladder cancer was attributable to cigarette smoking. Other smoking types (cigar, pipe, or ETS) were not associated with increased risks.     

Impact of smoking on patients with stage III colon cancer

BACKGROUND:

Cigarette smoking has been shown to increase the risk of developing colorectal cancer, particularly smoking early in life. Little is known about the impact of tobacco use on colon cancer recurrence among colon cancer survivors.

METHODS:

The authors prospectively collected lifetime smoking history from stage III colon cancer patients enrolled in a phase 3 trial via self‐report questionnaires during and 6 months after completion of adjuvant chemotherapy. Smoking status was defined as never, current, or past. Lifetime pack‐years were defined as number of lifetime packs of cigarettes. Patients were followed for recurrence or death.

RESULTS:

Data on smoking history were captured on 1045 patients with stage III colon cancer receiving adjuvant therapy (46% never smokers; 44% past; 10% current). The adjusted hazard ratio (HR) for disease‐free survival (DFS) was 0.99 (95% confidence interval [CI], 0.70‐1.41), 1.17 (95% CI 0.89‐1.55), and 1.22 (95% CI 0.92‐1.61) for lifetime pack‐years 0‐10, 10‐20, and 20+, respectively, compared with never smoking (P = .16). In a preplanned exploratory analysis of smoking intensity early in life, the adjusted HR for 12+ pack‐years before age 30 years for DFS was 1.37 (95% CI, 1.02‐1.84) compared with never smoking (P = .04). The adjusted HR for DFS was 1.18 (95% CI, 0.92‐1.50) for past smokers and 1.10 (95% CI, 0.73‐1.64) for current smokers, compared with never smokers.

CONCLUSIONS:

Total tobacco usage early in life may be an important, independent prognostic factor of cancer recurrences and mortality in patients with stage III colon cancer. Cancer 2010. © 2010 American Cancer Society.     

Impact of prediagnostic smoking and smoking cessation on colorectal cancer prognosis: a meta-analysis of individual patient data from cohorts within the CHANCES consortium

BackgroundSmoking has been associated with colorectal cancer (CRC) incidence and mortality in previous studies and might also be associated with prognosis after CRC diagnosis. However, current evidence on smoking in association with CRC prognosis is limited.Patients and methodsFor this individual patient data meta-analysis, sociodemographic and smoking behavior information of 12 414 incident CRC patients (median age at diagnosis: 64.3 years), recruited within 14 prospective cohort studies among previously cancer-free adults, was collected at baseline and harmonized across studies. Vital status and causes of death were collected for a mean follow-up time of 5.1 years following cancer diagnosis. Associations of smoking behavior with overall and CRC-specific survival were evaluated using Cox regression and standard meta-analysis methodology.ResultsA total of 5229 participants died, 3194 from CRC. Cox regression revealed significant associations between former [hazard ratio (HR) = 1.12; 95 % confidence interval (CI) = 1.04–1.20] and current smoking (HR = 1.29; 95% CI = 1.04–1.60) and poorer overall survival compared with never smoking. Compared with current smoking, smoking cessation was associated with improved overall (HR_{<10 years} = 0.78; 95% CI = 0.69–0.88; HR_{≥10 years} = 0.78; 95% CI = 0.63–0.97) and CRC-specific survival (HR_{≥10 years} = 0.76; 95% CI = 0.67–0.85).ConclusionIn this large meta-analysis including primary data of incident CRC patients from 14 prospective cohort studies on the association between smoking and CRC prognosis, former and current smoking were associated with poorer CRC prognosis compared with never smoking. Smoking cessation was associated with improved survival when compared with current smokers. Future studies should further quantify the benefits of nonsmoking, both for cancer prevention and for improving survival among CRC patients, in particular also in terms of treatment response.     

Snus use,smoking and survival among prostate cancer patients

Smoking is associated with prostate cancer mortality. The Scandinavian smokeless tobacco product snus is a source of nicotine but not the combustion products of smoke and has not been studied with respect to prostate cancer survival. The study is nested among 9,582 men with incident prostate cancer within a prospective cohort of 336,381 Swedish construction workers. Information on tobacco use was collected at study entry between 1971 and 1992, and categorized into (i) never users of any tobacco, (ii) exclusive snus: ever users of snus only, (iii) exclusive smokers: ever smokers (cigarette, cigar and/or pipe) only and (iv) ever users of both snus and smoking. Hazard ratios for prostate cancer‐specific and total mortality for smoking and snus use based on Cox proportional hazards models adjusted for age, calendar period at diagnosis and body mass index at baseline. During 36 years of follow‐up, 4,758 patients died—2,489 due to prostate cancer. Compared to never users of tobacco, exclusive smokers were at increased risk of prostate cancer mortality (HR 1.15, 95% CI: 1.05–1.27) and total mortality (HR 1.17, 95% CI: 1.09–1.26). Exclusive snus users also had increased risks for prostate cancer mortality (HR 1.24, 95% CI: 1.03–1.49) and total mortality (HR 1.19, 95% CI: 1.04–1.37). Among men diagnosed with nonmetastatic disease, the HR for prostate cancer death among exclusive snus users was 3.17 (95% CI: 1.66–6.06). The study is limited by a single assessment of tobacco use prior to diagnosis. Snus use was associated with increased risks of prostate cancer and total mortality among prostate cancer patients. This suggests that tobacco‐related components such as nicotine or tobacco‐specific carcinogens may promote cancer progression independent of tobacco's combustion products.     

Cigarette smoking and risk of glioma: a prospective cohort study

The etiology of glioma, the most commonly diagnosed malignant brain tumor among adults in the United States, is poorly understood. N-nitroso compounds are known carcinogens, which are found in cigarette smoke and can induce gliomas in rats. On this basis, it has been hypothesized that cigarette smoking may be associated with an increased risk of glioma. We investigated the association between cigarette smoking and glioma risk in the National Breast Screening Study, which included 89,835 Canadian women aged 40-59 years at recruitment between 1980 and 1985. Linkages to national cancer and mortality databases yielded data on cancer incidence and deaths from all causes, respectively, with follow-up ending between 1998 and 2000. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between cigarette smoking and risk of glioma. During a mean of 16.4 years of follow-up, we observed 120 incident glioma cases. Among ever smokers, women who reported having quit smoking had a 51% increase in risk of glioma compared with never smokers (HR = 1.51, 95% CI = 0.97-2.34), while current smokers did not appear to have an increase in risk. When the association with former smokers was further examined by years since quitting, women who had quit smoking >10 years before baseline were at a decreased risk of glioma compared with women who had quit within the 10 years prior to baseline (HR = 0.55, 95% CI = 0.29-1.07), indicating that the association between former smokers and glioma may be driven by women, who recently quit smoking. Compared with nonsmokers, duration of cigarette smoking, number of cigarettes smoked per day and pack-years of smoking were associated with increased glioma risk, although the increases in risk were relatively modest. The present study provides some support for a positive association between cigarette smoking and risk of glioma.     

Smoking and survival of colorectal cancer patients: Population‐based study from Germany

Current evidence on the association between smoking and colorectal cancer (CRC) prognosis after diagnosis is heterogeneous and few have investigated dose‐response effects or outcomes other than overall survival. Therefore, the association of smoking status and intensity with several prognostic outcomes was evaluated in a large population‐based cohort of CRC patients; 3,130 patients with incident CRC, diagnosed between 2003 and 2010, were interviewed on sociodemographic factors, smoking behavior, medication and comorbidities. Tumor characteristics were collected from medical records. Vital status, recurrence and cause of death were documented for a median follow‐up time of 4.9 years. Using Cox proportional hazards regression, associations between smoking characteristics and overall, CRC‐specific, non‐CRC related, recurrence‐free and disease‐free survival were evaluated. Among stage I–III patients, being a smoker at diagnosis and smoking ≥15 cigarettes/day were associated with lower recurrence‐free (adjusted hazard ratios (aHR): 1.29; 95% confidence interval (CI): 0.93–1.79 and aHR: 1.31; 95%‐CI: 0.92–1.87) and disease‐free survival (aHR: 1.26; 95%‐CI: 0.95–1.67 and aHR: 1.29; 95%‐CI: 0.94–1.77). Smoking was associated with decreased survival in stage I–III smokers with pack years ≥20 (Overall survival: aHR: 1.40; 95%‐CI: 1.01–1.95), in colon cancer cases (Overall survival: aHR: 1.51; 95%‐CI: 1.05–2.17) and men (Recurrence‐free survival: aHR: 1.51; 95%‐CI: 1.09–2.10; disease‐free survival: aHR: 1.49; 95%‐CI: 1.12–1.97), whereas no associations were seen among women, stage IV or rectal cancer patients. The observed patterns support the existence of adverse effects of smoking on CRC prognosis among nonmetastatic CRC patients. The potential to enhance prognosis of CRC patients by promotion of smoking cessation, embedded in tertiary prevention programs warrants careful evaluation in future investigations.     

Active and passive smoking and breast cancer risk in middle-aged Japanese women

To examine the hypothesis that tobacco smoke is associated with the risk of female breast cancer, we estimated the relative risks of active and passive smoke in middle-aged Japanese women in a population-based prospective study. The cohort consisted of residents in 4 public health center areas, aged 40 to 59 years. A self-administered questionnaire survey was conducted in 1990. This analysis included 21,805 subjects, 180 of whom had developed breast cancer by December 31, 1999. When the reference was defined as never-active smokers without passive smoking, adjusted relative risks (RRs) were 1.9 (95% confidence interval [CI] = 1.0-3.6) in current active smokers, 1.2 (95% CI = 0.4-4.0) in ex-active smokers and 1.2 (95% CI = 0.8-1.6) in never-active smokers with passive smoking. The elevated risk for ever-smokers was clearly observed in premenopausal women at baseline (RR = 3.9, 95% CI = 1.5-9.9) but not in postmenopausal women (RR = 1.1, 95% CI = 0.5-2.5). In never-active smokers, the adjusted RR for passive smoking, residential or occupational/public tobacco smoke exposure was 1.1 (95% CI = 0.8-1.6). In premenopausal women, passive smoking increased the risk (RR = 2.6; 95% CI = 1.3-5.2) but not in postmenopausal women (RR = 0.7; 95% CI = 0.4-1.0). We conclude that tobacco smoking increases the risk of female breast cancer in premenopausal women.     

Tobacco smoking and alcohol drinking at diagnosis of head and neck cancer and all‐cause mortality: Results from head and neck 5000, a prospective observational cohort of people with head and neck cancer

Tobacco smoking and alcohol consumption are well‐established risk factors for head and neck cancer. The prognostic role of smoking and alcohol intake at diagnosis have been less well studied. We analysed 1,393 people prospectively enrolled into the Head and Neck 5000 study (oral cavity cancer, n=403; oropharyngeal cancer, n=660; laryngeal cancer, n=330) and followed up for a median of 3.5 years. The primary outcome was all‐cause mortality. We used Cox proportional hazard models to derive minimally adjusted (age and gender) and fully adjusted (age, gender, ethnicity, stage, comorbidity, body mass index, HPV status, treatment, education, deprivation index, income, marital status, and either smoking or alcohol use) mortality hazard ratios (HR) for the effects of smoking status and alcohol intake at diagnosis. Models were stratified by cancer site, stage and HPV status. The fully‐adjusted HR for current versus never‐smokers was 1.7 overall (95% confidence interval [CI] 1.1, 2.6). In stratified analyses, associations of smoking with mortality were observed for oropharyngeal and laryngeal cancers (fully adjusted HRs for current smokers: 1.8 (95% CI=0.9, 3.40 and 2.3 (95% CI=0.8, 6.4)). We found no evidence that people who drank hazardous to harmful amounts of alcohol at diagnosis had a higher mortality risk compared to non‐drinkers (HR=1.2 (95% CI=0.9, 1.6)). There was no strong evidence that HPV status or tumour stage modified the association of smoking with survival. Smoking status at the time of a head and neck cancer diagnosis influenced all‐cause mortality in models adjusted for important prognostic factors.     

Active cigarette smoking and risk of breast cancer

Although epidemiological evidence on the role of active cigarette smoking in breast cancer risk has been inconsistent, recent literature supports a modest association between smoking and breast cancer. This association is particularly observed in women who smoke for a long duration, or who smoke for a long time prior to their first pregnancy. Here, we provide updated results on cigarette smoking and breast cancer risk in the Canadian National Breast Screening Study (NBSS). The NBSS is a large cohort of 89,835 women, aged 40–59, who were followed for a mean of 22.1 years, resulting in the ascertainment of 6,549 incident cases of breast cancer. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of cigarette smoking variables with breast cancer risk. We found breast cancer to be associated with duration (40 years vs. 0: HR = 1.57; 95%CI = 1.29–1.92), intensity (40 cigarettes per day vs. 0: HR = 1.21; 95%CI = 1.04–1.40), cumulative exposure (40 pack‐years vs. 0: HR = 1.19; 95%CI = 1.06–1.13) and latency (40 years since initiation vs. 0: HR = 1.19; 95%CI = 1.10–1.53) of cigarette smoking. Number of years smoked prior to first full‐term pregnancy was associated with higher risk of breast cancer than comparative years smoked post‐pregnancy (among parous women, 5 years pre pregnancy vs. 0: HR = 1.18; 95%CI = 1.10–1.26). These results strongly support a role for cigarette smoking in breast cancer etiology and emphasize the importance of timing of this exposure.     

Smoking,snus use and risk of right‐ and left‐sided colon,rectal and anal cancer: A 37‐year follow‐up study

Although some authorities consider smoking to be an established risk factor for colorectal cancer, the international literature is not entirely consistent. Further, only 1 study has addressed the association with smokeless tobacco and none with Scandinavian moist snuff (snus). This retrospective cohort study included 336,381 male Swedish construction workers with detailed information on tobacco use at cohort entry in 1971–1992. Complete follow‐up through 2007 was accomplished by means of linkage to population and health registers. Hazard ratios (HRs) and 95% confidence intervals (CIs) derived from Cox proportional hazards regression models estimated relative risks, adjusted for age and body mass index. Subjects who were never‐users of any tobacco served as reference. After up to 37 years of follow‐up, pure smoking was associated with a marginally increased risk of colon cancer (HR 1.08, 95% CI 0.99–1.19), a modestly elevated risk of rectal cancer (HR 1.16, 95% CI 1.04–1.30) and a substantial excess risk of anal cancer (HR 2.41, 95% CI 1.06–5.48). Snus use was not significantly associated with an increased risk of colorectal or anal cancer, although the point estimate for colon cancer was similar to that observed among smokers. Swedish data provide meager support for the association between tobacco use and colorectal cancer. A general tendency among Swedish men to quit smoking in recent decades might have attenuated true associations. A link between smoking and anal cancer was confirmed.     

Overall obesity, abdominal adiposity, diabetes and cigarette smoking in relation to the risk of pancreatic cancer in two Swedish population-based cohorts

We examined the associations of body mass index (BMI), waist circumference, a history of diabetes, and cigarette smoking with risk of pancreatic cancer among 37,147 women and 45,906 men followed up during 560,666 person-years in the Swedish Mammography Cohort and the Cohort of Swedish Men; 136 incident cases of pancreatic cancer were diagnosed. The multivariate rate ratio (RR) of pancreatic cancer for obese women and men (BMI > or =30 kg/m(2)) was 1.81 (95% CI: 1.04-3.15) compared to those with a BMI of 20-25 kg/m(2). For a difference of 20 cm (about two standard deviations) in waist circumference, the multivariate RRs were 1.32 (95% CI: 0.73-2.37) among women and 1.74 (95% CI: 1.00-3.01) among men. Pancreatic cancer risk was associated with history of diabetes (multivariate RR: 1.88; 95% CI: 1.09-3.26) and cigarette smoking (multivariate RR for current compared with never smokers: 3.06; 95% CI: 1.99-4.72). Current smokers of > or =40 pack-years had a five-fold elevated risk compared with never smokers. Risk among past smokers approached the RR for never smokers within 5-10 years following smoking cessation. Findings from this prospective study support positive relationships of overall obesity, abdominal adiposity, diabetes and smoking with risk of pancreatic cancer.     

Estimated intake of vitamin D and its interaction with vitamin A on lung cancer risk among smokers

Data are very limited on vitamin D and lung cancer prevention in high‐risk populations. The authors investigated whether estimated vitamin D intake was associated with lung cancer risk and whether effect modification by vitamin A existed among current/former heavy smokers and workers with occupational exposure to asbestos. A case–cohort study selected 749 incident lung cancers and 679 noncases from the Carotene and Retinol Efficacy Trial (CARET), 1988–2005. The active intervention was supplementation of 30 mg β‐carotene + 25,000 IU retinyl palmitate/day. Baseline total intake including both diet (from food frequency questionnaire) and personal supplements (from brand names linked to the labeled potencies) was assessed. Hazard ratios (HRs) were estimated by Cox proportional hazard models. No significant association of total vitamin D intake with lung cancer was observed overall. However, total vitamin D intake ≥600 versus <200 IU/day was associated with a lower risk of non‐small cell lung cancer among former smokers [HR = 0.36, 95% confidence interval (CI) = 0.13–0.96]. Total vitamin D intake ≥400 versus <400 IU/day was associated with a lower risk of total lung cancer among participants who received the CARET active intervention (HR = 0.56, 95% CI = 0.32–0.99) and among those who had total vitamin A intake ≥1,500 µg/day retinol activity equivalent (RAE; HR = 0.46, 95% CI = 0.23–0.91). The beneficial associations were attenuated among those who did not receive the CARET active intervention or who had total vitamin A intake <1,500 µg/day RAE (p‐interaction = 0.02 for current smokers). Our observation suggests that vitamin A may assist vitamin D in preventing lung cancer among smokers.     

Smoking and the risk of gastric cancer in the European Prospective Investigation Into Cancer and Nutrition (EPIC)

Smoking has recently been recognised as causally associated with the development of gastric cancer (GC). However, evidence on the effect by sex, duration and intensity of smoking, anatomic subsite and cessation of smoking is limited. Our objective was to assess the relation between tobacco use and GC incidence in the European Prospective Investigation into Cancer and Nutrition (EPIC). We studied data from 521,468 individuals recruited from 10 European countries taking part in the EPIC study. Participants completed lifestyle questionnaires that included questions on lifetime consumption of tobacco and diet in 1991-1998. Participants were followed until September 2002, and during that period 305 cases of stomach cancer were identified. After exclusions, 274 were eligible for the analysis, using the Cox proportional hazard model. After adjustment for educational level, consumption of fresh fruit, vegetables and preserved meat, alcohol intake and body mass index (BMI), there was a significant association between cigarette smoking and gastric cancer risk: the hazard ratio (HR) for ever smokers was 1.45 (95% confidence interval [CI] = 1.08-1.94). The HR of current cigarette smoking was 1.73 (95% CI = 1.06-2.83) in males and 1.87 (95% CI = 1.12-3.12) in females. Hazard ratios increased with intensity and duration of cigarette smoked. A significant decrease of risk was observed after 10 years of quitting smoking. A preliminary analysis of 121 cases with identified anatomic site showed that current cigarette smokers had a higher HR of GC in the cardia (HR = 4.10) than in the distal part of the stomach (HR = 1.94). In this cohort, 17.6 % (95% CI = 10.5-29.5 %) of GC cases may be attributable to smoking. Findings from this large study support the causal relation between smoking and gastric cancer in this European population. Stomach cancer should be added to the burden of diseases caused by smoking.     

Smoking,alcohol use,obesity, and overall survival from non‐Hodgkin lymphoma

BACKGROUND:

Smoking, alcohol use, and obesity appear to increase the risk of developing non‐Hodgkin lymphoma (NHL), but to the authors' knowledge, few studies to date have assessed their impact on NHL prognosis.

METHODS:

The association between prediagnosis cigarette smoking, alcohol use, and body mass index (BMI) and overall survival was evaluated in 1286 patients enrolled through population‐based registries in the United States from 1998 through 2000. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using Cox regression, adjusting for clinical and demographic factors.

RESULTS:

Through 2007, 442 patients had died (34%), and the median follow‐up for surviving patients was 7.7 years. Compared with never smokers, former (HR, 1.59; 95% CI, 1.12‐2.26) and current (HR, 1.50; 95% CI, 0.97‐2.29) smokers had poorer survival, and poorer survival was found to be positively associated with smoking duration, number of cigarettes smoked per day, pack‐years of smoking, and shorter time since quitting (all P <0.01). Alcohol use was associated with poorer survival (P = 0.03); compared with nonusers. Those drinking >43.1 g/week (median intake among drinkers) had poorer survival (HR, 1.55; 95% CI, 1.06‐2.27), whereas those drinkers consuming less than this amount demonstrated no survival disadvantage (HR, 1.13; 95% CI, 0.75‐1.71). Greater BMI was associated with poorer survival (P = 0.046), but the survival disadvantage was only noted among obese individuals (HR, 1.32 for BMI ≥30 vs BMI 20‐24.9; 95% CI, 1.02‐1.70). These results held for lymphoma‐specific survival and were broadly similar for diffuse large B‐cell lymphoma and follicular lymphoma.

CONCLUSIONS:

NHL patients who smoked, consumed alcohol, or were obese before diagnosis were found to have a poorer overall and lymphoma‐specific survival. Cancer 2010. © 2010 American Cancer Society.