Vegetarian diets and risk of all-cause mortality in a population-based prospective study in the United States.

The popularity of vegetarian diets has increased the need for studies on long-term health outcomes. A limited number of studies, including only one study from a non-vegetarian population, investigated the risk of mortality with self-identified vegetarianism and reported inconsistent results. This study evaluated prospective associations between vegetarian diets and all-cause mortality among 117,673 participants from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial cohort study. Vegetarian diet status was self-identified on the questionnaire. Deaths were ascertained from follow-up questionnaires and the National Death Index database. Multivariable Cox regression models were used to estimate the risk of all-cause mortality in hazard ratio (HR) and 95% confidence intervals (CI). By diet group, there were 116,894 omnivores (whose diet does not exclude animal products), 329 lacto- and/or ovo-vegetarians (whose diet excludes meat, but includes dairy and/or eggs), 310 pesco-vegetarians (whose diet excludes meat except for fish and seafood) and 140 vegans (whose diet excludes all animal products). After an average follow-up of 18 years, 39,763 participants were deceased. The risk of all-cause mortality did not statistically significantly differ among the four diet groups. Comparing with the omnivore group, the HR (95% CI) were 0.81 (0.64-1.03) for pesco-vegetarian group, 0.99 (0.80-1.22) for lacto- and/or ovo-vegetarian group and 1.27 (0.99-1.63) for vegan group, respectively. Similarly, mortality risk did not differ when comparing lacto- and/or ovo-vegetarians plus vegans with meat/fish eaters (omnivores and pesco-vegetarians) (HR [95% CI] = 1.09 [0.93-1.28]). As this study is one of the two studies of vegetarianism and mortality in non-vegetarian populations, further investigation is warranted.

Dairy product consumption and lung cancer risk: A prospective analysis.

BACKGROUND & AIM: Current evidence on prospective associations between dairy product, dairy fat and lactose intakes and lung cancer risk is limited and inconsistent. We conducted a prospective analysis of associations of lung cancer risk with dairy product intakes in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) cohort. METHODS: Pre-diagnostic dairy product intake was assessed through a validated Diet History Questionnaire. All incident lung cancer cases were pathologically verified. Multivariable Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for associations of lung cancer risk with intakes of total, full-fat, low-fat dairy, fermented or non-fermented dairy products; milk fat content preference; and intakes of total and saturated fats and lactose from dairy products. RESULTS: Among 101,709 adults (mean age of 65.5 years), a total of 1583 lung cancer cases were identified during 1,167,239 person-years of follow up. Mean total dairy product intake was 156 g/1000 kilocalories (kcal), including 20 g/1000 kcal from fermented dairy products. Total dairy intake was not associated with lung cancer risk (HR [95% CI] = 1.03 [0.89-1.18]) comparing the highest quartile with the lowest. Fermented dairy intake was inversely associated with lung cancer risk (0.85 [0.72-0.99]). In contrast, there were no statistically significant associations with low-fat, full-fat or non-fermented dairy product intakes. The preference of whole milk when consuming milk as beverage was associated with a higher risk of lung cancer than the preference of <0.5% fat milk (1.24 [1.03-1.49]). Total fat, saturated fat and lactose intakes from dairy products each were not associated with lung cancer risk. CONCLUSIONS: Our results suggest an inverse association of lung cancer risk with fermented dairy intake and a positive association with the whole milk preference in a US population. Future studies exploring underlying molecular mechanisms are warranted.

Calcium Intake and Lung Cancer Risk: A Pooled Analysis of 12 Prospective Cohort Studies.

BACKGROUND: Previous studies on calcium intake and lung cancer risk reported inconsistent associations, possibly due to the differences in intake amounts and contributing sources of calcium and smoking prevalence. OBJECTIVES: We investigated the associations of lung cancer risk with intake of calcium from foods and/or supplements and major calcium-rich foods in 12 studies. METHODS: Data from 12 prospective cohort studies conducted in the United States, Europe, and Asia were pooled and harmonized. We applied the DRI to categorize calcium intake based on the recommendations and quintile distribution to categorize calcium-rich food intake. We ran multivariable Cox regression by each cohort and pooled risk estimates to compute overall HR (95% CI). RESULTS: Among 1,624,244 adult men and women, 21,513 incident lung cancer cases were ascertained during a mean follow-up of 9.9 y. Overall, the dietary calcium intake was not significantly associated with lung cancer risk; the HRs (95% CI) were 1.08 (0.98-1.18) for higher (>1.5 RDA) and 1.01 (0.95-1.07) for lower intake (<0.5 RDA) comparing with recommended intake (EAR to RDA). Milk and soy food intake were positively or inversely associated with lung cancer risk [HR (95% CI) = 1.07 (1.02-1.12) and 0.92 (0.84-1.00)], respectively. The positive association with milk intake was significant only in European and North American studies (P-interaction for region = 0.04). No significant association was observed for calcium supplements. CONCLUSIONS: In this largest prospective investigation, overall, calcium intake was not associated with risk of lung cancer, but milk intake was associated with a higher risk. Our findings underscore the importance of considering food sources of calcium in studies of calcium intake.

Dietary Effects on Pain Symptoms in Patients with Fibromyalgia Syndrome: Systematic Review and Future Directions.

Fibromyalgia syndrome (FMS) is recognized for its difficulty to diagnose and its subjective symptomatology. There is neither a known cure nor a recommended therapeutic diet to aid in the multidisciplinary treatment. We conducted a systematic review to investigate if diets can improve pain symptoms of fibromyalgia. Through the PubMed search in March 2022, 126 abstracts were identified. We included both intervention and observational studies of diets and pain symptoms among patients with FMS. After screening titles, abstracts, and full-texts, 12 studies, including 11 intervention and one observational study, were selected. These studies included 546 participants and investigated plant-based diets (n = 3), anti-inflammatory diets (n = 1), gluten-free diets (n = 2), and elimination/restrictive diets (n = 6). These studies assessed pain symptoms through visual analogue scale for pain, fibromyalgia impact questionnaire/revised fibromyalgia impact questionnaire, tender point count, pain pressure threshold, and/or total myalgic score. Nine studies, including all three plant-based diet studies, reported statistically significant beneficial effects of their respective diets on pain symptom measurements. Given the small sample size and short intervention duration of the included studies, limited evidence currently exists to recommend any specific diet to patients with FMS. Further research is warranted to clarify specific diets to recommend and explore their potential mechanisms.

Prediagnosis Leisure-Time Physical Activity and Lung Cancer Survival: A Pooled Analysis of 11 Cohorts.

BACKGROUND: Little is known about the association between physical activity before cancer diagnosis and survival among lung cancer patients. In this pooled analysis of 11 prospective cohorts, we investigated associations of prediagnosis leisure-time physical activity (LTPA) with all-cause and lung cancer-specific mortality among incident lung cancer patients. METHODS: Using self-reported data on regular engagement in exercise and sports activities collected at study enrollment, we assessed metabolic equivalent hours (MET-h) of prediagnosis LTPA per week. According to the Physical Activity Guidelines for Americans, prediagnosis LTPA was classified into inactivity, less than 8.3 and at least 8.3 MET-h per week (the minimum recommended range). Cox regression was used to estimate hazard ratios (HRs) and 95% confidence interval (CIs) for all-cause and lung cancer-specific mortality after adjustment for major prognostic factors and lifetime smoking history. RESULTS: Of 20 494 incident lung cancer patients, 16 864 died, including 13 596 deaths from lung cancer (overall 5-year relative survival rate = 20.9%, 95% CI = 20.3% to 21.5%). Compared with inactivity, prediagnosis LTPA of more than 8.3 MET-h per week was associated with a lower hazard of all-cause mortality (multivariable-adjusted HR = 0.93, 95% CI = 0.88 to 0.99), but not with lung cancer-specific mortality (multivariable-adjusted HR = 0.99, 95% CI = 0.95 to 1.04), among the overall population. Additive interaction was found by tumor stage (Pinteraction = .008 for all-cause mortality and .003 for lung cancer-specific mortality). When restricted to localized cancer, prediagnosis LTPA of at least 8.3 MET-h per week linked to 20% lower mortality: multivariable-adjusted HRs were 0.80 (95% CI = 0.67 to 0.97) for all-cause mortality and 0.80 (95% CI = 0.65 to 0.99) for lung cancer-specific mortality. CONCLUSIONS: Regular participation in LTPA that met or exceeded the minimum Physical Activity Guidelines was associated with reduced hazards of mortality among lung cancer patients, especially those with early stage cancer.

Trends in Cardiovascular Disease by Asian American, Native Hawaiian, and Pacific Islander Ethnicity, Medicare Health Outcomes Survey 2011-2015.

BACKGROUND: The burden of cardiovascular disease (CVD) is increasing in the aging population. However, little is known about CVD risk factors and outcomes for Asian American, Native Hawaiian, and Other Pacific Islander (NH/PI) older adults by disaggregated subgroups. METHODS: Data were from the Centers for Medicare and Medicaid Services 2011-2015 Health Outcomes Survey, which started collecting expanded racial/ethnic data in 2011. Guided by Andersen and Newman's theoretical framework, multivariable logistic regression analyses were conducted to examine the prevalence and determinants of CVD risk factors (obesity, diabetes, smoking status, hypertension) and CVD conditions (coronary artery disease [CAD], congestive heart failure [CHF], myocardial infarction [MI], other heart conditions, stroke) for 10 Asian American and NH/PI subgroups and White adults. RESULTS: Among the 639 862 respondents, including 26 853 Asian American and 4 926 NH/PI adults, 13% reported CAD, 7% reported CHF, 10% reported MI, 22% reported other heart conditions, and 7% reported stroke. CVD risk factors varied by Asian American and NH/PI subgroup. The prevalence of overweight, obesity, diabetes, and hypertension was higher among most Asian American and NH/PI subgroups than White adults. After adjustment, Native Hawaiians had significantly greater odds of reporting stroke than White adults. CONCLUSIONS: More attention should focus on NH/PIs as a priority population based on the disproportionate burden of CVD risk factors compared with their White and Asian American counterparts. Future research should disaggregate racial/ethnic data to provide accurate depictions of CVD and investigate the development of CVD risk factors in Asian Americans and NH/PIs over the life course.

Diet and PPARG2 Pro12Ala Polymorphism Interactions in Relation to Cancer Risk: A Systematic Review.

Peroxisome proliferator-activated receptor-γ2 gene Pro12Ala allele polymorphism (PPARG2 Pro12Ala; rs1801282) has been linked to both cancer risk and dietary factors. We conducted the first systematic literature review of studies published before December 2020 using the PubMed database to summarize the current evidence on whether dietary factors for cancer may differ by individuals carrying C (common) and/or G (minor) alleles of the PPARG2 Pro12Ala allele polymorphism. The inclusion criteria were observational studies that investigated the association between food or nutrient consumption and risk of incident cancer stratified by PPARG2 Pro12Ala allele polymorphism. From 3815 identified abstracts, nine articles (18,268 participants and 4780 cancer cases) covering three cancer sites (i.e., colon/rectum, prostate, and breast) were included. CG/GG allele carriers were more impacted by dietary factors than CC allele carriers. High levels of protective factors (e.g., carotenoids and prudent dietary patterns) were associated with a lower cancer risk, and high levels of risk factors (e.g., alcohol and refined grains) were associated with a higher cancer risk. In contrast, both CG/GG and CC allele carriers were similarly impacted by dietary fats, well-known PPAR-γ agonists. These findings highlight the complex relation between PPARG2 Pro12Ala allele polymorphism, dietary factors, and cancer risk, which warrant further investigation.

Associations of coffee and tea consumption with lung cancer risk.

Associations of coffee and tea consumption with lung cancer risk have been inconsistent, and most lung cancer cases investigated were smokers. Included in this study were over 1.1 million participants from 17 prospective cohorts. Cox regression analyses were conducted to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Potential effect modifications by sex, smoking, race, cancer subtype and coffee type were assessed. After a median 8.6 years of follow-up, 20 280 incident lung cancer cases were identified. Compared with noncoffee and nontea consumption, HRs (95% CIs) associated with exclusive coffee drinkers (≥2 cups/d) among current, former and never smokers were 1.30 (1.15-1.47), 1.49 (1.27-1.74) and 1.35 (1.15-1.58), respectively. Corresponding HRs for exclusive tea drinkers (≥2 cups/d) were 1.16 (1.02-1.32), 1.10 (0.92-1.32) and 1.37 (1.17-1.61). In general, the coffee and tea associations did not differ significantly by sex, race or histologic subtype. Our findings suggest that higher consumption of coffee or tea is associated with increased lung cancer risk. However, these findings should not be assumed to be causal because of the likelihood of residual confounding by smoking, including passive smoking, and change of coffee and tea consumption after study enrolment.

Food intake of folate, folic acid and other B vitamins with lung cancer risk in a low-income population in the Southeastern United States.

PURPOSE: We prospectively examined associations of lung cancer risk with food intake of B vitamins involved in one-carbon metabolism and the use of folic acid-containing supplements among a low-income population of black and white adults in the Southeastern US. METHODS: Within the Southern Community Cohort Study, we included 1064 incident lung cancer cases among 68,236 participants aged 40-79 years at study enrollment. Food intake and the use of folic acid-containing supplements were assessed using a validated food frequency questionnaire at study enrollment. Multivariate Cox regression was used to estimate hazards ratios (HRs) and the 95% confidence intervals (CIs). RESULTS: Folate and/or folic acid intake from food were not associated with lung cancer risk; HRs (95% CI) for highest compared with lowest quartile were 1.08 (0.91-1.29) for total dietary folate, 1.00 (0.84-1.19) for food folate, and 1.09 (0.91-1.30) for food folic acid, respectively. Similarly, no associations were observed after stratifying by sex, race and smoking status, except for a positive association with total dietary folate intake among black women (HR 1.46, 95% CI 1.04-2.05 for the highest quartile compared with the lowest quartile, P trend = 0.02). Neither the use of folic acid-containing supplements nor food intake of vitamin B6, vitamin B12 and riboflavin were associated with lung cancer risk. CONCLUSIONS: Our findings do not support a protective effect of folate or folic acid for lung cancer prevention in a low-income population of black and white adults in the Southeastern US. Our finding of a positive association with total dietary folate intake among black women needs to be interpreted with caution and replicated in other studies.

Phytol and its metabolites phytanic and pristanic acids for risk of cancer: current evidence and future directions.

This review summarizes the current evidence on the potential role of phytol, a microbial metabolite of chlorophyl A, and its metabolites, phytanic and pristanic acids, in carcinogenesis. Primary food sources in Western diets are the nut skin for phytol and lipids in dairy, beef and fish for its metabolites. Phytol and its metabolites gained interest as dietary compounds for cancer prevention because, as natural ligands of peroxisome proliferator-activated receptor-α and -γ and retinoid X receptor, phytol and its metabolites have provided some evidence in cell culture studies and limited evidence in animal models of anti-carcinogenic, anti-inflammatory and anti-metabolic-syndrome properties at physiological concentrations. However, there may be a narrow range of efficacy, because phytol and its metabolites at supra-physiological concentrations can cause in vitro cytotoxicity in non-cancer cells and can cause morbidity and mortality in animal models. In human studies, evidence for a role of phytol and its metabolites in cancer prevention is currently limited and inconclusive. In short, phytol and its metabolites are potential dietary compounds for cancer prevention, assuming the challenges in preventing cytotoxicity in non-cancer cells and animal models and understanding phytol metabolism can be mitigated.

Association of Dietary Fiber and Yogurt Consumption With Lung Cancer Risk: A Pooled Analysis.

Importance: Dietary fiber (the main source of prebiotics) and yogurt (a probiotic food) confer various health benefits via modulating the gut microbiota and metabolic pathways. However, their associations with lung cancer risk have not been well investigated. Objective: To evaluate the individual and joint associations of dietary fiber and yogurt consumption with lung cancer risk and to assess the potential effect modification of the associations by lifestyle and other dietary factors. Design, Setting, and Participants: This pooled analysis included 10 prospective cohorts involving 1 445 850 adults from studies that were conducted in the United States, Europe, and Asia. Data analyses were performed between November 2017 and February 2019. Using harmonized individual participant data, hazard ratios and 95% confidence intervals for lung cancer risk associated with dietary fiber and yogurt intakes were estimated for each cohort by Cox regression and pooled using random-effects meta-analysis. Participants who had a history of cancer at enrollment or developed any cancer, died, or were lost to follow-up within 2 years after enrollment were excluded. Exposures: Dietary fiber intake and yogurt consumption measured by validated instruments. Main Outcomes and Measures: Incident lung cancer, subclassified by histologic type (eg, adenocarcinoma, squamous cell carcinoma, and small cell carcinoma). Results: The analytic sample included 627 988 men, with a mean (SD) age of 57.9 (9.0) years, and 817 862 women, with a mean (SD) age of 54.8 (9.7) years. During a median follow-up of 8.6 years, 18 822 incident lung cancer cases were documented. Both fiber and yogurt intakes were inversely associated with lung cancer risk after adjustment for status and pack-years of smoking and other lung cancer risk factors: hazard ratio, 0.83 (95% CI, 0.76-0.91) for the highest vs lowest quintile of fiber intake; and hazard ratio, 0.81 (95% CI, 0.76-0.87) for high vs no yogurt consumption. The fiber or yogurt associations with lung cancer were significant in never smokers and were consistently observed across sex, race/ethnicity, and tumor histologic type. When considered jointly, high yogurt consumption with the highest quintile of fiber intake showed more than 30% reduced risk of lung cancer than nonyogurt consumption with the lowest quintile of fiber intake (hazard ratio, 0.67 [95% CI, 0.61-0.73] in total study populations; hazard ratio, 0.69 [95% CI, 0.54-0.89] in never smokers), suggesting potential synergism. Conclusions and Relevance: Dietary fiber and yogurt consumption was associated with reduced risk of lung cancer after adjusting for known risk factors and among never smokers. Our findings suggest a potential protective role of prebiotics and probiotics against lung carcinogenesis.

Trends in Clinical Research Including Asian American, Native Hawaiian, and Pacific Islander Participants Funded by the US National Institutes of Health, 1992 to 2018.

Importance: Advancing the health equity agenda for Asian American, Native Hawaiian, and Pacific Islander (AA/NHPI) individuals has become an intersecting priority for federal agencies. However, the impact of federal investments and legislation to ensure systematic processes and resources to eliminate health disparities in AA/NHPI populations is unclear. Objective: To perform a portfolio review of clinical research funded by the National Institutes of Health (NIH) for AA/NHPI populations and determine the level of NIH investment in serving these populations. Design, Setting, and Participants: Cross-sectional study in which the NIH Research Portfolio Online Reporting Tools Expenditures and Results system was queried for extramural AA/NHPI-focused clinical research projects conducted in the United States from January 1, 1992, to December 31, 2018. Clinical research funded under research project grants, centers, cooperative awards, research career awards, training grants, and fellowships was included, with an advanced text search for AA/NHPI countries and cultures of origin. Project titles and terms were screened for inclusion and project abstracts were reviewed to verify eligibility. Descriptive analyses were completed. Main Outcomes and Measures: Outcomes included NIH funding trends and characteristics of funded projects and organizations. The proportions of AA/NHPI-related funding trends were calculated using 2 denominators, total NIH expenditures and clinical research expenditures. Results: There were 5460 records identified, of which 891 studies were reviewed for eligibility. Of these, 529 clinical research studies focused on AA/NHPI participants composed 0.17% of the total NIH budget over 26 years. Projects studying AA/NHPI individuals in addition to other populations were funded across 17 NIH institutes and centers. The top 5 funders collectively contributed almost 60% of the total funding dollars for AA/NHPI projects and were the National Cancer Institute ($231 584 664), National Institute on Aging ($108 365 124), National Heart, Lung, and Blood Institute ($67 232 910), National Institute on Minority Health and Health Disparities ($62 982 901), and National Institute on Mental Health ($60 072 779). Funding of these projects ($775 536 121) made up 0.17% of the overall NIH expenditures ($451 284 075 000) between 1992 and 2018, and 0.18% ($677 479 468) of the NIH research budget after 2000. Funding for AA/NHPI projects significantly increased over time, but the proportion of the total NIH budget has only increased from 0.12% before 2000 to 0.18% after 2000. Of total funding, 60.8% was awarded to research project grants compared with only 5.1% allocated to research career awards, training grants, and fellowships. Conclusions and Relevance: Increases in research dollars for AA/NHPI clinical research were not associated with increases in the overall NIH research budget, and underrepresentation of AA/NHPI subgroups still remains. Without overt direction from federal entities and dedicated funds for health disparities research, as well as parallel efforts to increase diversity in the biomedical workforce, investments may continue to languish for AA/NHPI populations.

Dairy Product Consumption and Prostate Cancer Risk in the United States.

An ongoing controversy exists regarding the effect of dairy products on prostate cancer risk in observational studies. We prospectively investigated the associations between dairy product consumption and prostate cancer risk among men in the United States. After calculating pre-diagnostic intake of individual or subgroups of dairy products using a validated food frequency questionnaire, we estimated hazard ratios (HR) and 95% confidence intervals (CI) for pathologically-verified cases of incident prostate cancer among men, overall, or stratified by severity. Among 49,472 men, 4134 were diagnosed with prostate cancer during an average follow-up period of 11.2 years. The median total dairy intake was 101 g/1000 kcal. Consumption of total, individual, or subgroups of dairy products was not statistically significantly associated with prostate cancer risk overall (HR = 1.05, 95% CI = 0.96-1.15 comparing the highest with lowest quartile) or stratified by severity, except for regular-fat dairy product intake with late-stage prostate cancer risk (HR = 1.37, 95% CI = 1.04-1.82 comparing the highest with lowest quartile) and 2%-fat milk intake with advanced prostate cancer risk (HR = 1.14, 95% CI = 1.02-1.28 comparing the higher than median intake with no intake group). Our findings do not support the previously reported harmful impact of dairy consumption on overall prostate cancer risk among men in the United States.

The role of coagulation and platelets in colon cancer-associated thrombosis.

Cancer-associated thrombosis is a common first presenting sign of malignancy and is currently the second leading cause of death in cancer patients after their malignancy. However, the molecular mechanisms underlying cancer-associated thrombosis remain undefined. In this study, we aimed to develop a better understanding of how cancer cells affect the coagulation cascade and platelet activation to induce a prothrombotic phenotype. Our results show that colon cancer cells trigger platelet activation in a manner dependent on cancer cell tissue factor (TF) expression, thrombin generation, activation of the protease-activated receptor 4 (PAR4) on platelets and consequent release of ADP and thromboxane A2. Platelet-colon cancer cell interactions potentiated the release of platelet-derived extracellular vesicles (EVs) rather than cancer cell-derived EVs. Our data show that single colon cancer cells were capable of recruiting and activating platelets and generating fibrin in plasma under shear flow. Finally, in a retrospective analysis of colon cancer patients, we found that the number of venous thromboembolism events was 4.5 times higher in colon cancer patients than in a control population. In conclusion, our data suggest that platelet-cancer cell interactions and perhaps platelet procoagulant EVs may contribute to the prothrombotic phenotype of colon cancer patients. Our work may provide rationale for targeting platelet-cancer cell interactions with PAR4 antagonists together with aspirin and/or ADP receptor antagonists as a potential intervention to limit cancer-associated thrombosis, balancing safety with efficacy.

Plasma selenoprotein P concentration and lung cancer risk: results from a case-control study nested within the Shanghai Men's Health Study.

Selenoprotein P (SELENOP) is a major selenoenzyme in plasma and linked to antioxidant properties and possibly to lung cancer; however, supporting evidence is limited. We investigated the association between pre-diagnostic plasma SELENOP concentration and lung cancer risk in a case-control study of 403 cases and 403 individually matched controls nested within the Shanghai Men's Health Study. SELENOP concentration in pre-diagnostic plasma samples was measured by a sandwich enzyme-linked immunosorbent assay. Cases were diagnosed with lung cancer between 2003 and 2010. Multivariate conditional logistic regression was used to estimate odds ratios (OR) and the corresponding 95% confidence intervals (CI) for studying the association between plasma SELENOP concentration and lung cancer risk. Cases had slightly lower plasma SELENOP concentration than controls (4.3 ± 1.2 versus 4.4 ± 1.1 mg/l, P difference = 0.09). However, the multivariate analysis showed no association between plasma SELENOP concentration and lung cancer risk among all participants (OR = 1.08, 95% CI = 0.54-2.14 for quartile 4 versus quartile 1), or by smoking status or tumor aggressiveness. In contrast, although the number of cases was limited, plasma SELENOP concentration was positively associated with lung adenocarcinoma risk (OR = 5.38, 95% CI = 1.89-15.35 for tertile 3 versus tertile 1), but not with squamous cell lung carcinoma (OR = 1.69, 95% CI = 0.43-6.70). Our study of adult men living in selenium non-deficient areas in China provides little support for the inverse association between pre-diagnostic plasma SELENOP concentration and lung cancer risk. Our finding of a positive association with risk of lung adenocarcinoma needs to be interpreted with caution.

The Role of Cruciferous Vegetables and Isothiocyanates for Lung Cancer Prevention: Current Status, Challenges, and Future Research Directions.

Lung cancer remains a leading cause of cancer-related deaths in the United States. Although smoking and air pollution exposure are primary risk factors of lung cancer, diet has also been reported to contribute to lung cancer risk. Cruciferous vegetables contain many bioactive compounds that alter the detoxification process of air-borne carcinogenic compounds and, thereby, may decrease lung cancer risk. In the meta-analysis of 31 observational studies, cruciferous vegetable intake is inversely associated with lung cancer risk (summary odds ratio/relative risk = 0.81 and 95% confidence interval = 0.74-0.89 for comparing the highest with lowest intake categories). More observational studies need to measure urinary isothiocyanate (ITC) concentrations and investigate their association with lung cancer risk in populations with relatively high intake of cruciferous vegetables. Current evidence is limited to two phase 2 clinical trials with incomplete reporting. Hence, more short-term clinical phase 2 trials need to examine effects of various amounts and types of cruciferous vegetables on biomarkers of risk and efficacy before a large phase 3 trial can be conducted to assess effects upon lung cancer risk. This would help further elucidate whether the inverse association observed with self-reported cruciferous vegetable intake is indeed due to ITC content or other bioactive compounds.

Overall and Central Obesity and Risk of Lung Cancer: A Pooled Analysis.

Background: The obesity-lung cancer association remains controversial. Concerns over confounding by smoking and reverse causation persist. The influence of obesity type and effect modifications by race/ethnicity and tumor histology are largely unexplored. Methods: We examined associations of body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR) with lung cancer risk among 1.6 million Americans, Europeans, and Asians. Cox proportional hazard regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with adjustment for potential confounders. Analyses for WC/WHR were further adjusted for BMI. The joint effect of BMI and WC/WHR was also evaluated. Results: During an average 12-year follow-up, 23 732 incident lung cancer cases were identified. While BMI was generally associated with a decreased risk, WC and WHR were associated with increased risk after controlling for BMI. These associations were seen 10 years before diagnosis in smokers and never smokers, were strongest among blacks, and varied by histological type. After excluding the first five years of follow-up, hazard ratios per 5 kg/m2 increase in BMI were 0.95 (95% CI = 0.90 to 1.00), 0.92 (95% CI = 0.89 to 0.95), and 0.89 (95% CI = 0.86 to 0.91) in never, former, and current smokers, and 0.86 (95% CI = 0.84 to 0.89), 0.94 (95% CI = 0.90 to 0.99), and 1.09 (95% CI = 1.03 to 1.15) for adenocarcinoma, squamous cell, and small cell carcinoma, respectively. Hazard ratios per 10 cm increase in WC were 1.09 (95% CI = 1.00 to 1.18), 1.12 (95% CI = 1.07 to 1.17), and 1.11 (95% CI = 1.07 to 1.16) in never, former, and current smokers, and 1.06 (95% CI = 1.01 to 1.12), 1.20 (95% CI = 1.12 to 1.29), and 1.13 (95% CI = 1.04 to 1.23) for adenocarcinoma, squamous cell, and small cell carcinoma, respectively. Participants with BMIs of less than 25 kg/m2 but high WC had a 40% higher risk (HR = 1.40, 95% CI = 1.26 to 1.56) than those with BMIs of 25 kg/m2 or greater but normal/moderate WC. Conclusions: The inverse BMI-lung cancer association is not entirely due to smoking and reverse causation. Central obesity, particularly concurrent with low BMI, may help identify high-risk populations for lung cancer.

Dietary Fat Intake and Lung Cancer Risk: A Pooled Analysis.

Purpose Dietary fat may play a role in lung carcinogenesis. Findings from epidemiologic studies, however, remain inconsistent. In this pooled analysis of 10 prospective cohort studies from the United States, Europe, and Asia, we evaluated the associations of total and specific types of dietary fat with lung cancer risk. Methods Cox regression was used to estimate hazard ratios (HRs) and 95% CIs in each cohort. Study-specific risk estimates were pooled by random- or fixed-effects meta-analysis. The first 2 years of follow-up were excluded to address potential influence of preclinical dietary changes. Results Among 1,445,850 participants, 18,822 incident cases were identified (mean follow-up, 9.4 years). High intakes of total and saturated fat were associated with an increased risk of lung cancer (for highest v lowest quintile: HR, 1.07 and 1.14, respectively; 95% CI, 1.00 to 1.15 and 1.07 to 1.22, respectively; P for trend for both < .001). The positive association of saturated fat was more evident among current smokers (HR, 1.23; 95% CI, 1.13 to 1.35; P for trend < .001) than former/never smokers ( P for interaction = .004), and for squamous cell and small cell carcinoma (HR, 1.61 and 1.40, respectively; 95% CI, 1.38 to 1.88 and 1.17 to 1.67, respectively; P for trend for both < .001) than other histologic types ( P for heterogeneity < .001). In contrast, a high intake of polyunsaturated fat was associated with a decreased risk of lung cancer (HR, 0.92; 95% CI, 0.87 to 0.98 for highest v lowest quintile; P for trend = .02). A 5% energy substitution of saturated fat with polyunsaturated fat was associated with a 16% to 17% lower risk of small cell and squamous cell carcinoma. No associations were found for monounsaturated fat. Conclusion Findings from this large, international cohort consortium suggest that modifying dietary fat intake (ie, replacing saturated fat with polyunsaturated fat) may reduce lung cancer risk, particularly among smokers and for squamous cell and small cell carcinoma.

Prediagnostic Calcium Intake and Lung Cancer Survival: A Pooled Analysis of 12 Cohort Studies.

Background: Lung cancer is the leading cause of cancer death. Little is known about whether prediagnostic nutritional factors may affect survival. We examined the associations of prediagnostic calcium intake from foods and/or supplements with lung cancer survival.Methods: The present analysis included 23,882 incident, primary lung cancer patients from 12 prospective cohort studies. Dietary calcium intake was assessed using food-frequency questionnaires at baseline in each cohort and standardized to caloric intake of 2,000 kcal/d for women and 2,500 kcal/d for men. Stratified, multivariable-adjusted Cox regression was applied to compute hazard ratios (HR) and 95% confidence intervals (CI).Results: The 5-year survival rates were 56%, 21%, and 5.7% for localized, regional, and distant stage lung cancer, respectively. Low prediagnostic dietary calcium intake (<500-600 mg/d, less than half of the recommendation) was associated with a small increase in risk of death compared with recommended calcium intakes (800-1,200 mg/d); HR (95% CI) was 1.07 (1.01-1.13) after adjusting for age, stage, histology, grade, smoking status, pack-years, and other potential prognostic factors. The association between low calcium intake and higher lung cancer mortality was evident primarily among localized/regional stage patients, with HR (95% CI) of 1.15 (1.04-1.27). No association was found for supplemental calcium with survival in the multivariable-adjusted model.Conclusions: This large pooled analysis is the first, to our knowledge, to indicate that low prediagnostic dietary calcium intake may be associated with poorer survival among early-stage lung cancer patients.Impact: This multinational prospective study linked low calcium intake to lung cancer prognosis. Cancer Epidemiol Biomarkers Prev; 26(7); 1060-70. ©2017 AACR.

Cohort Profile: The Shanghai Men's Health Study.

The Shanghai Men's Health Study (SMHS) is a population-based cohort study of 61,480 men aged 40-74 years, launched in 2002 in urban Shanghai to investigate the contribution of lifestyle/environmental factors and genetic susceptibility to cancer and other non-communicable diseases (NCDs). At baseline, trained interviewers collected detailed information on personal and dietary habits, occupational/medical history and physical activity, and took anthropometric measurements (response rate: 74%). Blood, urine and DNA were collected from 75%, 89% and 89% of participants, respectively. The cohort has been followed up through a combination of in-person surveys every 3-4 years and annual record linkage with cancer and vital statistics registries. Response rates for in-person follow-up surveys were over 91% and coverage for mortality nearly 100%. SMHS participants have a high smoking rate (58.6%) and moderate alcohol-drinking rate (29.3%), but low obesity rate (2.6%). They have a low calorie intake from fat (16.2% of total calorie intake) and protein (16.4%), high calorie intake from carbohydrates (67.4%), and high intake of soy food, cruciferous vegetables and fish (156.5, 110.6 and 51.7 g/day, respectively). With its unique exposure pattern and wealth of data and biological samples, the SMHS is well positioned for long-term research into NCD aetiology and prognosis. Information about accessing the SMHS resources can be found at: http://www.mc.vanderbilt.edu/swhs-smhs/.