The American Cancer Society Cancer Prevention Study II Nutrition Cohort: rationale, study design, and baseline characteristics

Lung cancer metabolomics: a pooled analysis in the Cancer Prevention Studies

BACKGROUND

A better understanding of lung cancer etiology and the development of screening biomarkers have important implications for lung cancer prevention.

METHODS

We included 623 matched case-control pairs from the Cancer Prevention Study (CPS) cohorts. Pre-diagnosis blood samples were collected between 1998 and 2001 in the CPS-II Nutrition cohort and 2006 and 2013 in the CPS-3 cohort and were sent for metabolomics profiling simultaneously. Cancer-free controls at the time of case diagnosis were 1:1 matched to cases on date of birth, blood draw date, sex, and race/ethnicity. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression, controlling for confounders. The Benjamini-Hochberg method was used to correct for multiple comparisons.

RESULTS

Sphingomyelin (d18:0/22:0) (OR: 1.32; 95% CI: 1.15, 1.53, FDR = 0.15) and taurodeoxycholic acid 3-sulfate (OR: 1.33; 95% CI: 1.14, 1.55, FDR = 0.15) were positively associated with lung cancer risk. Participants diagnosed within 3 years of blood draw had a 55% and 48% higher risk of lung cancer per standard deviation increase in natural log-transformed sphingomyelin (d18:0/22:0) and taurodeoxycholic acid 3-sulfate level, while 26% and 28% higher risk for those diagnosed beyond 3 years, compared to matched controls. Lipid and amino acid metabolism accounted for 47% to 80% of lung cancer-associated metabolites at P < 0.05 across all participants and subgroups. Notably, ever-smokers exhibited a higher proportion of lung cancer-associated metabolites (P < 0.05) in xenobiotic- and lipid-associated pathways, whereas never-smokers showed a more pronounced involvement of amino acid- and lipid-associated metabolic pathways.

CONCLUSIONS

This is the largest prospective study examining untargeted metabolic profiles regarding lung cancer risk. Sphingomyelin (d18:0/22:0), a sphingolipid, and taurodeoxycholic acid 3-sulfate, a bile salt, may be risk factors and potential screening biomarkers for lung cancer. Lipid and amino acid metabolism may contribute significantly to lung cancer etiology which varied by smoking status.

Health and Wellbeing of Regional and Rural Australian Healthcare Workers during the COVID-19 Pandemic: Baseline Cross-Sectional Findings from the Loddon Mallee Healthcare Worker COVID-19 Study-A Prospective Cohort Study

BACKGROUND

Coronavirus 19 (COVID-19) has created complex pressures and challenges for healthcare systems worldwide; however, little is known about the impacts COVID-19 has had on regional/rural healthcare workers. The Loddon Mallee Healthcare Worker COVID-19 Study (LMHCWCS) cohort was established to explore and describe the immediate and long-term impacts of the COVID-19 pandemic on regional and rural healthcare workers.

METHODS

Eligible healthcare workers employed within 23 different healthcare organisations located in the Loddon Mallee region of Victoria, Australia, were included. In this cohort study, a total of 1313 participants were recruited from November 2020-May 2021. Symptoms of depression, anxiety, post-traumatic stress, and burnout were measured using the Patient Health Questionnaire-9 (PHQ-9), Generalised Anxiety Disorder-7 (GAD-7), Impact of Events Scale-6 (IES-6), and Copenhagen Burnout Inventory (CBI), respectively. Resilience and optimism were measured using the Brief Resilience Scale and Life Orientation Test-Revised (LOT-R), respectively. Subjective fear of COVID-19 was measured using the Fear of COVID-19 Scale.

RESULTS

These cross-sectional baseline findings demonstrate that regional/rural healthcare workers were experiencing moderate/severe depressive symptoms (n = 211, 16.1%), moderate to severe anxiety symptoms (n = 193, 14.7%), and high personal or patient/client burnout with median total scores of 46.4 (IQR = 28.6) and 25.0 (IQR = 29.2), respectively. There was a moderate degree of COVID-19-related fear. However, most participants demonstrated a normal/high degree of resilience (n = 854, 65.0%). Based on self-reporting, 15.4% had a BMI from 18.5 to 24.9 kgm2 and 37.0% have a BMI of 25 kgm2 or over. Overall, 7.3% of participants reported they were current smokers and 20.6% reported alcohol consumption that is considered moderate/high-risk drinking. Only 21.2% of the sample reported consuming four or more serves of vegetables daily and 37.8% reported consuming two or more serves of fruit daily. There were 48.0% the sample who reported having poor sleep quality measured using the Pittsburgh Sleep Quality Index (PSQI).

CONCLUSION

Regional/rural healthcare workers in Victoria, Australia, were experiencing a moderate to high degree of psychological distress during the early stages of the pandemic. However, most participants demonstrated a normal/high degree of resilience. Findings will be used to inform policy options to support healthcare workers in responding to future pandemics.

Age at lung cancer diagnosis in females versus males who never smoke by race and ethnicity

BACKGROUND

We characterized age at diagnosis and estimated sex differences for lung cancer and its histological subtypes among individuals who never smoke.

METHODS

We analyzed the distribution of age at lung cancer diagnosis in 33,793 individuals across 8 cohort studies and two national registries from East Asia, the United States (US) and the United Kingdom (UK). Student's t-tests were used to assess the study population differences (Δ years) in age at diagnosis comparing females and males who never smoke across subgroups defined by race/ethnicity, geographic location, and histological subtypes.

RESULTS

We found that among Chinese individuals diagnosed with lung cancer who never smoke, females were diagnosed with lung cancer younger than males in the Taiwan Cancer Registry (n = 29,832) (Δ years = -2.2 (95% confidence interval (CI):-2.5, -1.9), in Shanghai (n = 1049) (Δ years = -1.6 (95% CI:-2.9, -0.3), and in Sutter Health and Kaiser Permanente Hawai'i in the US (n = 82) (Δ years = -11.3 (95% CI: -17.7, -4.9). While there was a suggestion of similar patterns in African American and non-Hispanic White individuals. the estimated differences were not consistent across studies and were not statistically significant.

CONCLUSIONS

We found evidence of sex differences for age at lung cancer diagnosis among individuals who never smoke.

Educational Attainment and Cancer Incidence in a Large Nationwide Prospective Cohort

BACKGROUND

Educational attainment is a social determinant of health and frequently used as an indicator of socioeconomic status. Educational attainment is a predictor of cancer mortality, but associations with site-specific cancer incidence are variable. The aim of this study was to evaluate the association of educational attainment and site-specific cancer incidence adjusting for known risk factors in a large prospective cohort.

METHODS

Men and women enrolled in the American Cancer Society's Cancer Prevention Study-II Nutrition Cohort who were cancer free at baseline were included in this study (n = 148,965). Between 1992 and 2017, 22,810 men and 17,556 women were diagnosed with incident cancer. Cox proportional hazards regression models were used to estimate age- and multivariable-adjusted risk and 95% confidence intervals of total and site-specific cancer incidence in persons with lower versus higher educational attainment.

RESULTS

Educational attainment was inversely associated with age-adjusted cancer incidence among men but not women. For specific cancer sites, the multivariable-adjusted risk of cancer in the least versus most educated individuals remained significant for colon, rectum, and lung cancer among men and lung and breast cancer among women.

CONCLUSIONS

Educational attainment is associated with overall and site-specific cancer risk though adjusting for cancer risk factors attenuates the association for most cancer sites.

IMPACT

This study provides further evidence that educational attainment is an important social determinant of cancer but that its effects are driven by associated behavioral risk factors suggesting that targeting interventions toward those with lower educational attainment is an important policy consideration.

Combining Asian and European genome-wide association studies of colorectal cancer improves risk prediction across racial and ethnic populations

Polygenic risk scores (PRS) have great potential to guide precision colorectal cancer (CRC) prevention by identifying those at higher risk to undertake targeted screening. However, current PRS using European ancestry data have sub-optimal performance in non-European ancestry populations, limiting their utility among these populations. Towards addressing this deficiency, we expand PRS development for CRC by incorporating Asian ancestry data (21,731 cases; 47,444 controls) into European ancestry training datasets (78,473 cases; 107,143 controls). The AUC estimates (95% CI) of PRS are 0.63(0.62-0.64), 0.59(0.57-0.61), 0.62(0.60-0.63), and 0.65(0.63-0.66) in independent datasets including 1681-3651 cases and 8696-115,105 controls of Asian, Black/African American, Latinx/Hispanic, and non-Hispanic White, respectively. They are significantly better than the European-centric PRS in all four major US racial and ethnic groups (p-values < 0.05). Further inclusion of non-European ancestry populations, especially Black/African American and Latinx/Hispanic, is needed to improve the risk prediction and enhance equity in applying PRS in clinical practice.

Combining Asian-European Genome-Wide Association Studies of Colorectal Cancer Improves Risk Prediction Across Race and Ethnicity

Polygenic risk scores (PRS) have great potential to guide precision colorectal cancer (CRC) prevention by identifying those at higher risk to undertake targeted screening. However, current PRS using European ancestry data have sub-optimal performance in non-European ancestry populations, limiting their utility among these populations. Towards addressing this deficiency, we expanded PRS development for CRC by incorporating Asian ancestry data (21,731 cases; 47,444 controls) into European ancestry training datasets (78,473 cases; 107,143 controls). The AUC estimates (95% CI) of PRS were 0.63(0.62-0.64), 0.59(0.57-0.61), 0.62(0.60-0.63), and 0.65(0.63-0.66) in independent datasets including 1,681-3,651 cases and 8,696-115,105 controls of Asian, Black/African American, Latinx/Hispanic, and non-Hispanic White, respectively. They were significantly better than the European-centric PRS in all four major US racial and ethnic groups (p-values<0.05). Further inclusion of non-European ancestry populations, especially Black/African American and Latinx/Hispanic, is needed to improve the risk prediction and enhance equity in applying PRS in clinical practice.

Circulating plasma phospholipid fatty acid levels and breast cancer risk in the Cancer Prevention Study-II Nutrition Cohort

Prospective studies that objectively measure circulating levels of fatty acids are needed to clarify their role in the etiology of breast cancer. Thirty-eight phospholipid fatty acids were measured using gas chromatograph in the plasma fraction of blood samples collected prospectively from 2718 postmenopausal women (905 breast cancer cases) enrolled in the Cancer Prevention Study II Nutrition Cohort. Associations of 28 fatty acids that passed quality control metrics (modeled as per 1-SD increase) with breast cancer risk were assessed using multiple variable conditional logistic regression models to compute odds ratios (OR) and 95% confidence intervals (CI). The false discovery rate (q value) was computed to account for multiple comparisons. Myristic acid levels were positively associated with breast cancer risk (OR, 1.17, 95% CI: 1.07-1.28; q value = 0.03). Borderline associations were also found for palmitoleic acid (OR, 1.14, 95% CI: 1.04-1.24) and desaturation index16 (OR, 1.10, 95% CI: 1.01-1.20) at nominal P values (<.03) (q values>0.05). These findings suggest that higher circulating levels of myristic acid, sourced from dietary intake of palm kernel oils along with increased de novo synthesis of fatty acids, may increase breast cancer risk. Additional studies are needed to investigate de novo synthesis of fatty acid in breast cancer tissues.

Lung cancer in never smokers: Distinct population-based patterns by age, sex, and race/ethnicity

OBJECTIVES

Epidemiological patterns for lung cancer among never smokers (LCNS) are largely unknown, even though LCNS cases comprise 15% of lung cancers. Past studies were based on epidemiologic or health system cohorts, and not fully representative of the underlying population. The objective was to analyze rates (and trends) of LCNS by sex, age group, and race and ethnicity based on all-inclusive truly population-based sources.

MATERIALS AND METHODS

Individual-level data from 2014 to 2018 on smoking status among microscopically-confirmed lung cancer cases from Florida's cancer registry were combined with population denominators adjusted with NHIS data on smoking prevalence to compute population-based LCNS incidence rates and rate ratios. Incidence rates and proportional mortality were ranked against other cancers. Joinpoint regression analyses examined trends.

RESULTS

Proportions of LCNS ranged from 9% among White men to 83% among Chinese women. Overall, LCNS was 13% (IRR 1.13, 95%CI 1.08-1.17) more common among men than women, but variation occurred by age group, with female rates exceeding male in younger ages. Age-adjusted rates per 100,000 were highest among Asian/Pacific Islander (API) men and women (15.3 and 13.5, respectively) and Black populations (14.6, 12.9), intermediate for White (13.2, 11.8) and lowest among the Hispanic population (12.1, 10.6). Among API women, LCNS was the second leading cause of cancer death, surpassed only by breast cancer. LCNS trends were stable over time.

CONCLUSION

LCNS is the 11th most frequently occurring cancer in men and 8th in women. LCNS differences by race/ethnicity are small, within a 15% range of the White population's rates. Surprisingly, API men and women have the highest LCNS rates and proportional mortality. As smoking prevalence decreases in the US, LCNS cases will inevitably increase, warranting inquiry into risk factors across the lifespan.

The Role of Individual-Level Factors in Rural Mortality Disparities

Introduction

The role of individual risk factors in the rural‒urban mortality disparity is poorly understood. The purpose of this study was to explore the role of individual-level demographics and health behaviors on the association between rural residence and the risk of mortality.

Methods

Cancer Prevention Study-II participants provided updated addresses throughout the study period. Rural‒Urban Commuting Area codes were assigned to participants' geocoded addresses as a time-varying exposure. Cox proportional hazards regression was used to estimate hazard ratios and 95% CIs for mortality associated with Rural‒Urban Commuting Area groups.

Results

After adjustment for age and sex, residents of rural areas/small towns had a small but statistically significant elevated risk of all-cause mortality compared with metropolitan residents (hazard ratio=1.04; 95% CI=1.01, 1.06). Adjustment for additional covariates attenuated the association entirely (hazard ratio=0.99; 95% CI=0.97, 1.01). Individually, adjustment for education (hazard ratio=0.99; 95% CI=0.97, 1.01), alcohol use (hazard ratio=1.01; 95% CI=0.99, 1.04), and moderate-to-vigorous intensity aerobic physical activity (hazard ratio=1.00; 95% CI=0.97, 1.02) eliminated the elevated risk.

Conclusions

The elevated risk of death for rural compared with that for metropolitan residents appeared to be largely explained by individual-level demographics and health behaviors. If replicated in other subpopulations, these results suggest that modifiable factors may play an important role in reducing the rural mortality disparity.

Age-related health deficits and five-year mortality among older, long-term cancer survivors

INTRODUCTION

Geriatric assessment evaluates multiple domains of health that, together, are superior to using chronologic age for predicting outcomes, such as hospitalization and mortality among patients with cancer. Most studies have not included comparison groups of individuals without cancer and assessed domains around the time of initial cancer diagnosis. Further, the potential for brief, self-reported measures to capture deficits that similarly predict mortality has not been well examined. This study compared age-related health deficit prevalence between older, long-term cancer survivors and individuals without a cancer history, and estimated associations between deficits and mortality risk among survivors.

MATERIALS AND METHODS

Analyses included participants in the Cancer Prevention Study (CPS)-II Nutrition Cohort who were cancer-free at enrollment in 1992/1993 and completed the Patient Reported Outcome Measurement Information System® (PROMIS®) global health questionnaire in 2011. Age-related deficits in five domains (comorbidities, functional status, mental health, malnutrition/weight loss, and social support) were self-reported. Cancer information was self-reported and confirmed via medical records or state cancer registries. Vital status through 2016 and cause of death was ascertained by linkage with the National Death Index.

RESULTS

Analyses included 9979 participants (median age = 80) diagnosed with invasive cancer 5-20 years prior to completing the 2011 survey and 63,578 participants without a cancer history (median age = 79). Overall deficits in the five domains were similar among long-term cancer survivors and controls. However, survivors of specific cancer types - non-Hodgkin lymphoma (NHL), lung, and kidney cancer - were more likely to report deficits in mental health and functional status than the control group. Among all survivors, each domain was independently associated with all-cause mortality, particularly functional status (hazard ratio [HR] = 2.02; 95% confidence interval [CI]: 1.80-2.27) and mental health (HR = 1.84; 95% CI: 1.65-2.04). Mortality risk increased with the number of deficits.

DISCUSSION

These results suggest that, several years after treatment, NHL, lung, and kidney cancer survivors are still more likely to experience age-related deficits compared to other similarly-aged individuals. Furthermore, results show that shorter, self-reported physical and mental health assessments, such as the PROMIS® global health questions, are predictive of mortality among older, long-term cancer survivors and, therefore, may be useful in clinical and research settings.

Genetic variants associated with circulating C-reactive protein levels and colorectal cancer survival: Sex-specific and lifestyle factors specific associations

Elevated blood levels of C-reactive protein (CRP) have been linked to colorectal cancer (CRC) survival. We evaluated genetic variants associated with CRP levels and their interactions with sex and lifestyle factors in association with CRC-specific mortality. Our study included 16 142 CRC cases from the International Survival Analysis in Colorectal Cancer Consortium. We identified 618 common single nucleotide polymorphisms (SNPs) associated with CRP levels from the NHGRI-EBI GWAS Catalog. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between SNPs and CRC-specific mortality adjusting for age, sex, genotyping platform/study and principal components. We investigated their interactions with sex and lifestyle factors using likelihood ratio tests. Of 5472 (33.9%) deaths accrued over up to 10 years of follow-up, 3547 (64.8%) were due to CRC. No variants were associated with CRC-specific mortality after multiple comparison correction. We observed strong evidence of interaction between variant rs1933736 at FRK gene and sex in relation to CRC-specific mortality (corrected Pinteraction  = .0004); women had higher CRC-specific mortality associated with the minor allele (HR = 1.11, 95% CI = 1.04-1.19) whereas an inverse association was observed for men (HR = 0.88, 95% CI = 0.82-0.94). There was no evidence of interactions between CRP-associated SNPs and alcohol, obesity or smoking. Our study observed a significant interaction between sex and a CRP-associated variant in relation to CRC-specific mortality. Future replication of this association and functional annotation of the variant are needed.

Loddon Mallee healthcare worker COVID-19 study-protocol for a prospective cohort study examining the health and well-being of rural Australian healthcare workers during the COVID-19 pandemic

INTRODUCTION

The COVID-19 pandemic is creating immense psychosocial disturbance. While global, broad-based research is being conducted, little is known about the effects of the COVID-19 pandemic on health and well-being or how protective and resilience factors influence the human response in Australian rural and regional communities. Rural and regional communities often have less resources to deal with such public health emergencies and face additional environmental adversity. Healthcare workers, including those in rural and regional areas, have felt the immediate impacts of COVID-19 in a multitude of ways and these impacts will continue for years to come. Therefore, this study aims to describe and understand the impacts of the COVID-19 pandemic on the rural and regional healthcare workforce within the Loddon Mallee region, Victoria, Australia.

METHODS AND ANALYSIS

This prospective cohort of rural and regional healthcare workers will be recruited and followed over 3 years to examine the effects of the COVID-19 pandemic on their health and well-being. Self-administered online questionnaires will be administered every 6 months for a 36-month period. Multiple outcomes will be assessed; however, the primary outcomes are emotional health and well-being and psychological resilience. Emotional health and well-being will be measured using validated instruments that will assess multiple domains of the emotional health and well-being continuum.Linear and logistic regression and latent growth curve modelling will be used to examine the association between baseline and follow-up participant emotional health, well-being and resilience while adjusting for potentially time-varying confounding variables. Participant characteristics measured at baseline will also be tested for association with incident health, morbidity, mortality and health service utilisation outcomes at follow-up.

ETHICS AND DISSEMINATION

Ethical approval has been obtained through the Bendigo Health Human Research Ethics Committee. The study findings will be disseminated through international conferences, international peer-reviewed journals and social media.

TRIAL REGISTRATION NUMBER

ACTRN12620001269921.

Premature Mortality Due to Tobacco-Related Malignancies in Poland

Introduction

Although in Poland at the turn of the 20th and 21st centuries, tobacco consumption per capita was one of the highest in the world as a result of specific political and social conditions, nicotinism was the most common preventable cause of death that reduced life expectancy by 10 years on average. The aim of this study is to determine the level of premature mortality and its trends by age and sex for tobacco-related malignancies in Poland in the years 2008–2017.

Methods

The standardised premature mortality rates as well as mortality rates for five-year age ranges according to the patients’ sex were used. The Joinpoint model was used to determine the time trends.

Results

Premature mortality due to all tobacco-dependent cancers analysed decreased in Poland throughout the analysed period in both male (2.5% per year) and female (1% per year) populations. A detailed analysis of individual diseases showed that a decrease in premature mortality was observed for almost all malignancies with the exception of malignant liver cancer among males, malignant oesophageal cancer among females and malignant lip, oral cavity and oropharyngeal cancer in both sexes. The reduction in mortality from all tobacco-related cancers in the male population was greatest between 40 and 44 years of age, reaching 5.6% year on year. Similarly, in the case of females, the decline in mortality was greater in the younger age cohorts and decreased in those aged over 50.

Conclusion

The favourable phenomenon of decreasing the level of premature mortality caused by tobacco-related malignancies may be associated, among others, with the policy of primary prevention of these diseases in the form of a widespread ban on smoking in public places, intensive information campaigns on the harmfulness of tobacco smoking and increasing taxation on tobacco products.

Prospective investigation of polyomavirus infection and the risk of adult glioma

Glioma is an aggressive primary tumor of the brain with a poorly understood etiology. We studied the association of 4 human polyomaviruses (HPyV)—JC virus (JCV), BK virus (BKV), human polyomavirus 6 (HPyV6), and Merkel cell polyomavirus (MCPyV) with glioma risk within the Cancer Prevention Study II in the US (CPS-II) and the Janus Serum Bank in Norway. Cohort participants subsequently diagnosed with glioma from the CPS-II (n = 37) and Janus Serum Bank (n = 323), a median of 6.9 and 15.4 years after blood collection, respectively, were matched to individual controls on age, sex, and date of blood draw. Serum antibodies to the major viral capsid protein (VP1) were used to establish infection history for each polyomavirus. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. In the Janus Serum Bank, MCPyV infection was associated with a higher risk of glioma overall (OR: 1.56; 95% CI 1.10, 2.19). A modest, nonsignificant positive association with MCPyV infection was also observed in CPS-II (OR: 1.29; 95% CI 0.54, 3.08). In both cohorts, glioma risk was not significantly related to infection with JCV, BKV or HPyV6. The present study suggests that MCPyV infection may increase glioma risk.

Frequency of Pathogenic Germline Variants in Cancer-Susceptibility Genes in the Childhood Cancer Survivor Study

Background

Pediatric cancers are the leading cause of death by disease in children despite improved survival rates overall. The contribution of germline genetic susceptibility to pediatric cancer survivors has not been extensively characterized. We assessed the frequency of pathogenic or likely pathogenic (P/LP) variants in 5451 long-term pediatric cancer survivors from the Childhood Cancer Survivor Study.

Methods

Exome sequencing was conducted on germline DNA from 5451 pediatric cancer survivors (cases who survived ≥5 years from diagnosis; n = 5105 European) and 597 European cancer-free adults (controls). Analyses focused on comparing the frequency of rare P/LP variants in 237 cancer-susceptibility genes and a subset of 60 autosomal dominant high-to-moderate penetrance genes, for both case-case and case-control comparisons.

Results

Of European cases, 4.1% harbored a P/LP variant in high-to-moderate penetrance autosomal dominant genes compared with 1.3% in controls (2-sided P = 3 × 10-4). The highest frequency of P/LP variants was in genes typically associated with adult onset rather than pediatric cancers, including BRCA1/2, FH, PALB2, PMS2, and CDKN2A. A statistically significant excess of P/LP variants, after correction for multiple tests, was detected in patients with central nervous system cancers (NF1, SUFU, TSC1, PTCH2), Wilms tumor (WT1, REST), non-Hodgkin lymphoma (PMS2), and soft tissue sarcomas (SDHB, DICER1, TP53, ERCC4, FGFR3) compared with other pediatric cancers.

Conclusion

In long-term pediatric cancer survivors, we identified P/LP variants in cancer-susceptibility genes not previously associated with pediatric cancer as well as confirmed known associations. Further characterization of variants in these genes in pediatric cancer will be important to provide optimal genetic counseling for patients and their families.

A Metabolomics Analysis of Postmenopausal Breast Cancer Risk in the Cancer Prevention Study II

Breast cancer is the most common cancer in women, but its incidence can only be partially explained through established risk factors. Our aim was to use metabolomics to identify novel risk factors for breast cancer and to validate recently reported metabolite-breast cancer findings. We measured levels of 1275 metabolites in prediagnostic serum in a nested case-control study of 782 postmenopausal breast cancer cases and 782 matched controls. Metabolomics analysis was performed by Metabolon Inc using ultra-performance liquid chromatography and a Q-Exactive high resolution/accurate mass spectrometer. Controls were matched by birth date, date of blood draw, and race/ethnicity. Odds ratios (ORs) and 95% confidence intervals (CIs) of breast cancer at the 90th versus 10th percentile (modeled on a continuous basis) of metabolite levels were estimated using conditional logistic regression, with adjustment for age. Twenty-four metabolites were significantly associated with breast cancer risk at a false discovery rate <0.20. For the nine metabolites positively associated with risk, the ORs ranged from 1.75 (95% CI: 1.29–2.36) to 1.45 (95% CI: 1.13–1.85), and for the 15 metabolites inversely associated with risk, ORs ranged from 0.59 (95% CI: 0.43–0.79) to 0.69 (95% CI: 0.55–0.87). These metabolites largely comprised carnitines, glycerolipids, and sex steroid metabolites. Associations for three sex steroid metabolites validated findings from recent studies and the remainder were novel. These findings contribute to growing data on metabolite-breast cancer associations by confirming prior findings and identifying novel leads for future validation efforts.

Optimizing the quality of clinical studies on oral microbiome: A practical guide for planning, performing, and reporting

With this review, we aim to increase the quality standards for clinical studies with microbiome as an output parameter. We critically address the existing body of evidence for good quality practices in oral microbiome studies based on 16S rRNA gene amplicon sequencing. First, we discuss the usefulness of microbiome profile analyses. Is a microbiome study actually the best approach for answering the research question? This is followed by addressing the criteria for the most appropriate study design, sample size, and the necessary data (study metadata) that should be collected. Next, we evaluate the available evidence for best practices in sample collection, transport, storage, and DNA isolation. Finally, an overview of possible sequencing options (eg, 16S rRNA gene hypervariable regions, sequencing platforms), processing and data interpretation approaches, as well as requirements for meaningful data storage, sharing, and reporting are provided.

Contribution of Germline Predisposition Gene Mutations to Breast Cancer Risk in African American Women

BACKGROUND

The risks of breast cancer in African American (AA) women associated with inherited mutations in breast cancer predisposition genes are not well defined. Thus, whether multigene germline hereditary cancer testing panels are applicable to this population is unknown. We assessed associations between mutations in panel-based genes and breast cancer risk in 5054 AA women with breast cancer and 4993 unaffected AA women drawn from 10 epidemiologic studies.

METHODS

Germline DNA samples were sequenced for mutations in 23 cancer predisposition genes using a QIAseq multiplex amplicon panel. Prevalence of mutations and odds ratios (ORs) for associations with breast cancer risk were estimated with adjustment for study design, age, and family history of breast cancer.

RESULTS

Pathogenic mutations were identified in 10.3% of women with estrogen receptor (ER)-negative breast cancer, 5.2% of women with ER-positive breast cancer, and 2.3% of unaffected women. Mutations in BRCA1, BRCA2, and PALB2 were associated with high risks of breast cancer (OR = 47.55, 95% confidence interval [CI] = 10.43 to >100; OR = 7.25, 95% CI = 4.07 to 14.12; OR = 8.54, 95% CI = 3.67 to 24.95, respectively). RAD51D mutations were associated with high risk of ER-negative disease (OR = 7.82, 95% CI = 1.61 to 57.42). Moderate risks were observed for CHEK2, ATM, ERCC3, and FANCC mutations with ER-positive cancer, and RECQL mutations with all breast cancer.

CONCLUSIONS

The study identifies genes that predispose to breast cancer in the AA population, demonstrates the validity of current breast cancer testing panels for use in AA women, and provides a basis for increased referral of AA patients for cancer genetic testing.

Analysis of β-catenin association with obesity in African Americans with premalignant and malignant colorectal lesions

BACKGROUND

African Americans (AA) are at high risk for Colorectal Cancer (CRC). Studies report a 30-60% increase in CRC risk with physical inactivity, obesity and metabolic syndrome. Activation of the WNT/β-catenin (CTNNB1) signaling pathway plays a critical role in colorectal carcinogenesis. Accumulating evidence also indicates a role of WNT-CTNNB1 signaling in obesity and metabolic diseases.

AIM

To examine the association between obesity, β-Catenin expression and colonic lesions in African Americans.

METHODS

We reviewed the pathology records of 152 colorectal specimens from 2010 to 2012 (46 CRCs, 74 advanced adenomas and 32 normal colon tissues). Tissue Microarrays (TMA) were constructed from these samples. Immunohistochemistry (IHC) for CTNNB1 (β-Catenin; clone β-Catenin-1) was performed on the constructed TMAs. The IHC results were evaluated by 2 pathologists and the nuclear intensity staining was scored from 0 to 4. BMI, sex, age, location of the lesion and other demographic data were obtained.

RESULTS

Positive nuclear staining in normal, advanced adenoma and CRC was 0, 24 and 41%, respectively (P < 0.001). CRC was asso ciated with positive status for nuclear CTNNB1 intensity (adjusted OR: 3.40, 95%CI = 1.42-8.15, P = 0.006 for positive nuclear staining) compared to non-CRC samples (Normal or advanced adenoma). Nuclear staining percentage has a fair diagnostic ability for CRC with an AUC of 0.63 (95%CI = 0.55-0.71). Overweight/obese patients (BMI > 25) did not show a significant difference in (p = 0.3) nuclear CTNNB1 staining (17% positive in normal weight vs. 27% positive in overweight/obese). The association between nuclear intensity and CRC was not different between normal and overweight patients (P for interaction = 0.6). The positive nuclear CTNNB1status in CRC stage III and IV (35% of all CRC) was not different from stage I and II (50% vs. 36%, respectively, P = 0.4).

CONCLUSION

In our study, advanced adenoma and CRC were associated with activation of β-catenin in physically fit, overweight and obese patients. Thus, obesity and WNT/β-Catenin pathway seem to be independent in African American patients. WNT/β-Catenin signaling pathway has a potential to be used as an effector in colon carcinogenic transformation. Whether or not BMI is a modifier of this pathway needs to be investigated further.

Relationship Between Muscle-Strengthening Activity and Cause-Specific Mortality in a Large US Cohort

INTRODUCTION

Muscle-strengthening activity (MSA) has beneficial effects on hypertension, glucose homeostasis, and other health conditions; however, its association with mortality is not as well understood.

METHODS

We analyzed data from the Cancer Prevention Study-II Nutrition Cohort (data collection 1982-2014), a prospective US cohort that consisted of 72,462 men and women who were free of major chronic diseases; 18,034 of the cohort died during 13 years of follow-up (2001-2014). We used Cox proportional hazards modeling, controlling for various potential confounding factors, to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for MSA (none, >0 to <1 h/wk, 1 to <2 h/wk, and ≥2 h/wk) in relation to mortality risk, independent of and in combination with aerobic physical activity.

RESULTS

The association between MSA and mortality appeared to be nonlinear (quadratic trend P value, <.001). After multivariable adjustment and comparison with no MSA, engaging in less than 2 hours per week of MSA was associated with lowered all-cause mortality (>0 to <1 h/wk: HR = 0.88, 95% CI, 0.82-0.94; 1 to <2 h/wk: HR = 0.90, 95% CI, 0.84-0.97), but engaging in 2 or more hours per week was not associated with reduced risk (HR = 1.01; 95% CI, 0.92-1.09). Associations were similar but not significant for cancer mortality. Engaging in >0 to <1 hr/wk of MSA was associated with a 19% lower risk (HR = 0.81; 95% CI, 0.71-0.92) of cardiovascular disease mortality, but more time spent in MSA was not associated with reduced risk (quadratic trend P value =.005). Associations did not vary by amount of moderate-to-vigorous aerobic physical activity.

CONCLUSION

Engaging in ≥2 hours per week of MSA was associated with lower all-cause mortality, independent of aerobic activity. Reasons for the lack of association with higher amounts of MSA are unclear. Our findings support recommending muscle-strengthening activities for overall health.

Medical conditions and physical function deficits among multiple primary cancer survivors

PURPOSE

Survivors of multiple primary cancers make up a sizable proportion of all cancer survivors, yet little is known about the health of this population. We examined the prevalence of medical conditions and physical function deficits among multiple primary survivors compared with single primary survivors and individuals without a cancer history.

METHODS

Participants were enrolled in the Cancer Prevention Study (CPS)-II Nutrition Cohort in 1992/1993. Prevalent medical conditions (diabetes, heart conditions, cerebrovascular conditions, emphysema/chronic bronchitis, osteoporosis, osteoarthritis), physical function limitations, use of a cane or walker, balance difficulties, and falls within the past year were assessed on a follow-up survey completed in 2011. We estimated age- and sex-adjusted prevalence ratios (PRs), comparing multiple primary survivors (N = 1003) to single primary survivors (N = 12,849) and participants without cancer (N = 63,578).

RESULTS

The prevalence of medical conditions did not differ substantially between multiple primary survivors and either comparison group. However, multiple primary survivors were more likely to report severe limitations in physical function than the single primary (PR = 1.48 (95% CI, 1.28-1.71)) and no-cancer (PR = 1.64 (95% CI, 1.42-1.88)) groups. Using a cane or walker and balance difficulties were also significantly more common among multiple primary survivors.

CONCLUSIONS

Despite a similar prevalence of comorbid medical conditions, severe functional limitations were significantly more common among multiple primary survivors than single primary survivors or individuals without cancer.

IMPLICATIONS FOR CANCER SURVIVORS

Assessment of functional status and treatment of physical deficits may be an especially critical component of care for older patients with a history of multiple cancer diagnoses.

Association of Oral Microbiome With Risk for Incident Head and Neck Squamous Cell Cancer

Importance

Case-control studies show a possible relationship between oral bacteria and head and neck squamous cell cancer (HNSCC). Prospective studies are needed to examine the temporal relationship between oral microbiome and subsequent risk of HNSCC.

Objective

To prospectively examine associations between the oral microbiome and incident HNSCC.

Design, Setting, and Participants

This nested case-control study was carried out in 2 prospective cohort studies: the American Cancer Society Cancer Prevention Study II Nutrition Cohort (CPS-II) and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). Among 122 004 participants, 129 incident patient cases of HNSCC were identified during an average 3.9 years of follow-up. Two controls per patient case (n = 254) were selected through incidence density sampling, matched on age, sex, race/ethnicity, and time since mouthwash collection. All participants provided mouthwash samples and were cancer-free at baseline.

Exposures

Oral microbiome composition and specific bacterial abundances were determined through bacterial 16S rRNA gene sequencing. Overall oral microbiome composition and specific taxa abundances were compared for the case group and the control group, using PERMANOVA and negative binomial generalized linear models, respectively, controlling for age, sex, race, cohort, smoking, alcohol, and oral human papillomavirus-16 status. Taxa with a 2-sided false discovery rate (FDR)-adjusted P-value (q-value) <.10 were considered significant.

Main Outcomes and Measures

Incident HNSCC.

Results

The study included 58 patient cases from CPS-II (mean [SD] age, 71.0 [6.4] years; 16 [27.6%] women) and 71 patient cases from PLCO (mean [SD] age, 62.7 [4.8] years; 13 [18.3%] women). Two controls per patient case (n = 254) were selected through incidence density sampling, matched on age, sex, race/ethnicity, and time since mouthwash collection. Head and neck squamous cell cancer cases and controls were similar with respect to age, sex, and race. Patients in the case group were more often current tobacco smokers, tended to have greater alcohol consumption (among drinkers), and to be positive for oral carriage of papillomavirus-16. Overall microbiome composition was not associated with risk of HNSCC. Greater abundance of genera Corynebacterium (fold change [FC], 0.58; 95% confidence interval [CI], 0.41-0.80; q = .06) and Kingella (FC, 0.63; 95% CI, 0.46-0.86; q = .08) were associated with decreased risk of HNSCC, potentially owing to carcinogen metabolism capacity. These findings were consistent for both cohorts and by cohort follow-up time. The observed relationships tended to be stronger for larynx cancer and for individuals with a history of tobacco use.

Conclusions and Relevance

This study demonstrates that greater oral abundance of commensal Corynebacterium and Kingella is associated with decreased risk of HNSCC, with potential implications for cancer prevention.

The Consortium of Metabolomics Studies (COMETS): Metabolomics in 47 Prospective Cohort Studies

The Consortium of Metabolomics Studies (COMETS) was established in 2014 to facilitate large-scale collaborative research on the human metabolome and its relationship with disease etiology, diagnosis, and prognosis. COMETS comprises 47 cohorts from Asia, Europe, North America, and South America that together include more than 136,000 participants with blood metabolomics data on samples collected from 1985 to 2017. Metabolomics data were provided by 17 different platforms, with the most frequently used labs being Metabolon, Inc. (14 cohorts), the Broad Institute (15 cohorts), and Nightingale Health (11 cohorts). Participants have been followed for a median of 23 years for health outcomes including death, cancer, cardiovascular disease, diabetes, and others; many of the studies are ongoing. Available exposure-related data include common clinical measurements and behavioral factors, as well as genome-wide genotype data. Two feasibility studies were conducted to evaluate the comparability of metabolomics platforms used by COMETS cohorts. The first study showed that the overlap between any 2 different laboratories ranged from 6 to 121 metabolites at 5 leading laboratories. The second study showed that the median Spearman correlation comparing 111 overlapping metabolites captured by Metabolon and the Broad Institute was 0.79 (interquartile range, 0.56-0.89).

Gestational weight gain and optimal wellness (GLOW): rationale and methods for a randomized controlled trial of a lifestyle intervention among pregnant women with overweight or obesity

BACKGROUND

Excess gestational weight gain (GWG) is common among women with overweight or obesity, increasing their risks for pregnancy complications, delivering a large infant, and postpartum weight retention. To date, only intensive interventions have had success and few interventions have been designed for implementation in healthcare settings.

METHODS

We describe the development, rationale, and methods of GLOW (GestationaL Weight Gain and Optimal Wellness), a randomized controlled trial evaluating the efficacy of a lifestyle intervention to prevent excess GWG among racially/ethnically diverse women with overweight or obesity in an integrated healthcare delivery system. Participants in Kaiser Permanente Northern California will be randomized, within 2 weeks of completing a study baseline clinic visit at 10 weeks' gestation, to either usual medical care or a multi-component pregnancy lifestyle intervention adapted from the Diabetes Prevention Program (target N = 400). Informed by focus groups with patients and designed to be feasible in a clinical setting, the intervention will include 13 weekly individual sessions (11 delivered by telephone) focused on behavior change for weight management, healthy eating, physical activity, and stress management. Outcomes will be assessed in women and their infants from randomization to 12 months postpartum. The primary outcome is GWG. Secondary outcomes include changes in diet and physical activity during pregnancy and infant birthweight. Exploratory outcomes include cardiometabolic profile assessed via pregnancy blood samples and cord blood samples; and postpartum weight retention and infant anthropometrics up to 12 months of age. The trial includes systematic approaches to enhance intervention fidelity, intervention adherence, and participant retention in trial assessments.

DISCUSSION

GLOW is among few trials targeting excess GWG among diverse women with overweight or obesity in a healthcare setting, with long-term maternal and infant outcomes assessed up to 12 months after delivery. This evaluation of a multi-component intervention is designed to produce generalizable results to inform potential adoption of the intervention in clinical settings.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT02130232 ): submitted April 30, 2014; posted May 5, 2014.

Social Isolation and Mortality in US Black and White Men and Women

Social isolation is associated with higher mortality in studies comprising mostly white adults, yet associations among black adults are unclear. In this prospective cohort study, we evaluated whether associations of social isolation with all-cause, cardiovascular disease, and cancer mortality differed by race and sex. Adults enrolled in Cancer Prevention Study II in 1982/1983 were followed for mortality through 2012 (n = 580,182). Sex- and race-specific multivariable-adjusted hazard ratios and 95% confidence intervals were estimated for associations of a 5-point social isolation score with risk of death. Social isolation was associated with all-cause mortality in all subgroups (P for trend ≤ 0.005); for the most isolated versus the least isolated, the hazard ratios were 2.34 (95% confidence interval (CI): 1.58, 3.46) and 1.60 (95% CI: 1.41, 1.82) among black men and white men, respectively (P for interaction = 0.40) and 2.13 (95% CI: 1.44, 3.15) and 1.84 (95% CI: 1.68, 2.01) among black women and white women, respectively (P for interaction = 0.89). The association did not differ between black men and black women (P for interaction = 0.33) but was slightly stronger in white women than in white men (P for interaction = 0.01). Social isolation was associated with cardiovascular disease mortality in each subgroup (P for trend < 0.03) but with cancer mortality only among whites (P for trend < 0.0001). Subgroup differences in the influence of specific social isolation components were identified. Identifying and intervening with socially isolated adults could improve health outcomes.

Serologic Response to Helicobacter pylori Proteins Associated With Risk of Colorectal Cancer Among Diverse Populations in the United States

BACKGROUND & AIMS

Previous studies reported an association of the bacteria Helicobacter pylori, the primary cause of gastric cancer, and risk of colorectal cancer (CRC). However, these findings have been inconsistent, appear to vary with population characteristics, and may be specific for virulence factor VacA. To more thoroughly evaluate the potential association of H pylori antibodies with CRC risk, we assembled a large consortium of cohorts representing diverse populations in the United States.

METHODS

We used H pylori multiplex serologic assays to analyze serum samples from 4063 incident cases of CRC, collected before diagnosis, and 4063 matched individuals without CRC (controls) from 10 prospective cohorts for antibody responses to 13 H pylori proteins, including virulence factors VacA and CagA. The association of seropositivity to H pylori proteins, as well as protein-specific antibody level, with odds of CRC was determined by conditional logistic regression.

RESULTS

Overall, 40% of controls and 41% of cases were H pylori-seropositive (odds ratio [OR], 1.09; 95% CI, 0.99-1.20). H pylori VacA-specific seropositivity was associated with an 11% increased odds of CRC (OR, 1.11; 95% CI, 1.01-1.22), and this association was particularly strong among African Americans (OR, 1.45; 95% CI, 1.08-1.95). Additionally, odds of CRC increased with level of VacA antibody in the overall cohort (P = .008) and specifically among African Americans (P = .007).

CONCLUSIONS

In an analysis of a large consortium of cohorts representing diverse populations, we found serologic responses to H pylori VacA to associate with increased risk of CRC risk, particularly for African Americans. Future studies should seek to understand whether this marker is related to virulent H pylori strains carried in these populations.

Prevalence of pathogenic/likely pathogenic variants in the 24 cancer genes of the ACMG Secondary Findings v2.0 list in a large cancer cohort and ethnicity-matched controls

Background

Prior research has established that the prevalence of pathogenic/likely pathogenic (P/LP) variants across all of the American College of Medical Genetics (ACMG) Secondary Findings (SF) genes is approximately 0.8–5%. We investigated the prevalence of P/LP variants in the 24 ACMG SF v2.0 cancer genes in a family-based cancer research cohort (n = 1173) and in cancer-free ethnicity-matched controls (n = 982).

Methods

We used InterVar to classify variants and subsequently conducted a manual review to further examine variants of unknown significance (VUS).

Results

In the 24 genes on the ACMG SF v2.0 list associated with a cancer phenotype, we observed 8 P/LP unique variants (8 individuals; 0.8%) in controls and 11 P/LP unique variants (14 individuals; 1.2%) in cases, a non-significant difference. We reviewed 115 VUS. The median estimated per-variant review time required was 30 min; the first variant within a gene took significantly (p = 0.0009) longer to review (median = 60 min) compared with subsequent variants (median = 30 min). The concordance rate was 83.3% for the variants examined by two reviewers.

Conclusion

The 115 VUS required database and literature review, a time- and labor-intensive process hampered by the difficulty in interpreting conflicting P/LP determinations. By rigorously investigating the 24 ACMG SF v2.0 cancer genes, our work establishes a benchmark P/LP variant prevalence rate in a familial cancer cohort and controls.

Electronic supplementary material

The online version of this article (10.1186/s13073-018-0607-5) contains supplementary material, which is available to authorized users.

Prolonged Leisure Time Spent Sitting in Relation to Cause-Specific Mortality in a Large US Cohort

The majority of leisure time is spent in sedentary behaviors such as television viewing. Studies have documented that prolonged leisure-time sitting is associated with higher risk of mortality-total, cardiovascular disease, cancer, and "all other causes"-but few have examined the "other" causes of death in detail. To examine associations of leisure-time sitting with risk of specific causes of death, we analyzed data from the Cancer Prevention Study II (CPS-II) Nutrition Cohort, a prospective US cohort including 127,554 men and women who were free of major chronic disease at study entry, and among whom 48,784 died during 21 years of follow-up (1993-2014; median follow-up, 20.3 years, interquartile range, 4.6 years). After multivariable adjustment, prolonged leisure-time sitting (≥6 vs. <3 hours per day) was associated with higher risk of mortality from all causes, cardiovascular disease (including coronary heart disease and stroke-specific mortality), cancer, diabetes, kidney disease, suicide, chronic obstructive pulmonary disease, pneumonitis due to solids and liquids, liver, peptic ulcer and other digestive disease, Parkinson disease, Alzheimer disease, nervous disorders, and musculoskeletal disorders. These findings provide additional evidence for associations between a broad range of mortality outcomes and prolonged sitting time. Given the pervasive nature of sitting in the contemporary lifestyle, this study further supports the recommendation that encouraging individuals to reduce sedentary time may provide health benefits.

Antibody Responses to Streptococcus Gallolyticus Subspecies Gallolyticus Proteins in a Large Prospective Colorectal Cancer Cohort Consortium

Background: Antibody responses to Streptococcus gallolyticus subspecies gallolyticus (SGG) proteins, especially pilus protein Gallo2178, have been consistently associated with colorectal cancer risk. Previous case-control studies and prospective studies with up to 8 years of follow-up, however, were unable to decipher the temporality of antibody responses to SGG in the context of the long-term multistep development of colorectal cancer. In this study, we analyzed a large U.S. colorectal cancer cohort consortium with follow-up beyond 10 years for antibody responses to SGG.Methods: We applied multiplex serology to measure antibody responses to 9 SGG proteins in participants of 10 prospective U.S. cohorts (CLUE, CPSII, HPFS, MEC, NHS, NYUWHS, PHS, PLCO, SCCS, and WHI) including 4,063 incident colorectal cancer cases and 4,063 matched controls. Conditional logistic regression was used to assess whether antibody responses to SGG were associated with colorectal cancer risk, overall and by time between blood draw and diagnosis.Results: Colorectal cancer risk was increased among those with antibody responses to Gallo2178, albeit not statistically significant [OR, 1.23; 95% confidence interval (CI), 0.99-1.52]. This association was stronger for cases diagnosed <10 years after blood draw (OR, 1.40; 95% CI, 1.09-1.79), but was not found among cases diagnosed ≥10 years after blood draw (OR, 0.79; 95% CI, 0.50-1.24).Conclusions: In a large cohort consortium, we reproduced the association of antibody responses to SGG Gallo2178 with colorectal cancer risk for individuals diagnosed within 10 years after blood draw.Impact: This timing-specific finding suggests that antibody responses to SGG are associated with increased colorectal cancer risk only after tumorigenesis has begun. Cancer Epidemiol Biomarkers Prev; 27(10); 1186-94. ©2018 AACR.

Fine mapping in TERT-CLPTM1L region identified three independent lung cancer susceptibility signals: A large-scale multi-ethnic population study

Genome-wide association studies (GWAS) and fine mapping studies have identified multiple lung cancer susceptibility variants in TERT-CLPTM1L region. However, it is still unclear about the relationship between these risk variants and the independent lung cancer risk signals in this region. Therefore, we evaluated the independent susceptibility signals for lung cancer and explored the potential functional variants in this region. Sequential conditional analysis was used to detect the independent susceptibility loci based on four lung cancer GWAS datasets with 12 843 lung cases and 12 639 controls. Comprehensively functional annotations were performed for each independent signal. Three independent susceptibility signals were identified in multi-ethnic population. For the first signal, rs2736100 showed the most significant association with lung cancer risk (C > A, OR = 0.82, 95%CI: 0.79-0.85, P = 1.98 × 10^-25 ). Rs36019446 was the top-ranked site (A > G, OR = 0.88, 95%CI: 0.84-0.92, P = 1.74 × 10^-9 ) in the second signal. For the third signal, rs326048 was the leading SNP (A > G, OR = 0.91, 95%CI: 0.87-0.95, P = 1.38 × 10^-5 ). The following subgroup analysis found the same three loci among Asian population. Further, we compared the difference between various subgroup populations. Functional annotations revealed that rs2736100, rs27996 (r²  = 0.85 with rs36019446) and rs326049 (r²  = 0.73 with rs326048) could be potential functional variants in these three risk signals, respectively. In conclusion, although multiple variants have been found associated with lung cancer risk in TERT-CLPTM1L region, our findings indicated that there are three independent lung cancer susceptibility signals in this region.

Comparison of the oral microbiome in mouthwash and whole saliva samples

Population-based epidemiologic studies can provide important insight regarding the role of the microbiome in human health and disease. Buccal cells samples using commercial mouthwash have been obtained in large prospective cohorts for the purpose of studying human genomic DNA. We aimed to better understand if these mouthwash samples are also a valid resource for the study of the oral microbiome. We collected one saliva sample and one Scope mouthwash sample from 10 healthy subjects. Bacterial 16S rRNA genes from both types of samples were amplified, sequenced, and assigned to bacterial taxa. We comprehensively compared these paired samples for bacterial community composition and individual taxonomic abundance. We found that mouthwash samples yielded similar amount of bacterial DNA as saliva samples (p from Student's t-test for paired samples = 0.92). Additionally, the paired samples had similar within sample diversity (p from = 0.33 for richness, and p = 0.51 for Shannon index), and clustered as pairs for diversity when analyzed by unsupervised hierarchical cluster analysis. No significant difference was found in the paired samples with respect to the taxonomic abundance of major bacterial phyla, Bacteroidetes, Firmicutes, Proteobacteria, Fusobacteria, and Actinobacteria (FDR adjusted q values from Wilcoxin signed-rank test = 0.15, 0.15, 0.87, 1.00 and 0.15, respectively), and all identified genera, including genus Streptococcus (q = 0.21), Prevotella (q = 0.25), Neisseria (q = 0.37), Veillonella (q = 0.73), Fusobacterium (q = 0.19), and Porphyromonas (q = 0.60). These results show that mouthwash samples perform similarly to saliva samples for analysis of the oral microbiome. Mouthwash samples collected originally for analysis of human DNA are also a resource suitable for human microbiome research.

Walking in Relation to Mortality in a Large Prospective Cohort of Older U.S. Adults

INTRODUCTION

Engaging in >150 minutes of moderate-intensity or 75 minutes of vigorous-intensity physical activity weekly is recommended for optimal health. The relationship between walking, the most common activity especially for older adults, and total mortality is not well documented.

METHODS

Data from a large U.S. prospective cohort study including 62,178 men (mean age 70.7 years) and 77,077 women (mean age 68.9 years), among whom 24,688 men and 18,933 women died during 13 years of follow-up (1999-2012), were used to compute multivariable-adjusted hazard rate ratios and 95% CIs for walking as the sole form of activity or adjusted for other moderate- or vigorous-intensity physical activity in relation to total and cause-specific mortality (data analysis 2015-2016).

RESULTS

Inactivity compared with walking only at less than recommended levels was associated with higher all-cause mortality (hazard rate ratio=1.26, 95% CI=1.21, 1.31). Meeting one to two times the recommendations through walking only was associated with lower all-cause mortality (hazard rate ratio=0.80, 95% CI=0.78, 0.83). Associations with walking adjusted for other moderate- or vigorous-intensity physical activity were similar to walking only. Walking was most strongly associated with respiratory disease mortality followed by cardiovascular disease mortality and then cancer mortality.

CONCLUSIONS

In older adults, walking below minimum recommended levels is associated with lower all-cause mortality compared with inactivity. Walking at or above physical activity recommendations is associated with even greater decreased risk. Walking is simple, free, and does not require any training, and thus is an ideal activity for most Americans, especially as they age.

Pre-diagnostic plasma urate and the risk of amyotrophic lateral sclerosis

OBJECTIVE

To prospectively examine for the first time the association between plasma urate levels measured in healthy participants and future amyotrophic lateral sclerosis (ALS) risk.

METHODS

A pooled case-control study nested in five US prospective cohorts comprising 319,617 participants who provided blood, of which 275 had ALS during follow-up. Pre-diagnostic plasma urate was determined for all participants using a clinical colorimetric enzyme assay. Gender-specific multivariable-adjusted rate ratios (RR) of ALS incidence or death estimated by conditional logistic regression and pooled using inverse-variance weighting.

RESULTS

In age- and matching factor-adjusted analyses, a 1 mg/dL increase in urate concentration was associated with RR = 0.88 (95% CI: [0.78, 0.997] p = 0.044). After adjustment for BMI, a strong predictor of ALS and urate levels, and other potential covariates, the RR = 0.89 (95% CI: [0.78, 1.02]; p = 0.08 for 1mg/dL increase in urate).

CONCLUSION

Elevation of plasma urate was modestly inversely associated with the risk of ALS and warrants further study for a potential role in this disease.

The prevalence of DICER1 pathogenic variation in population databases

The DICER1 syndrome is associated with a variety of rare benign and malignant tumors, including pleuropulmonary blastoma (PPB), cystic nephroma (CN) and Sertoli-Leydig cell tumor (SLCT). The prevalence and penetrance of pathogenic DICER1 variation in the general population is unknown. We examined three publicly-available germline whole exome sequence datasets: Exome Aggregation Consortium (ExAC), 1,000 Genomes (1,000 G) and the Exome Sequencing Project (ESP). To avoid over-estimation of pathogenic DICER1 variation from cancer-associated exomes, we excluded The Cancer Genome Atlas (TCGA) variants from ExAC. All datasets were annotated with snpEff and ANNOVAR and variants were classified into four categories: likely benign (LB), unknown significance (VUS), likely pathogenic (LP), or pathogenic (P). The prevalence of DICER1 P/LP variants was 1:870 to 1:2,529 in ExAC-nonTCGA (53,105 exomes) estimated by metaSVM and REVEL/CADD, respectively. A more stringent prevalence calculation considering only loss-of-function and previously-published pathogenic variants detected in ExAC-nonTCGA, yielded a prevalence of 1:10,600. Despite the rarity of most DICER1 syndrome tumors, pathogenic DICER1 variation is more common than expected. If confirmed, these findings may inform future sequencing-based newborn screening programs for PPB, CN and SLCT, in which early detection improves prognosis.

The relationship between physical activity, obesity, and lung cancer risk by smoking status in a large prospective cohort of US adults

Physical activity has been associated with lower lung cancer risk in numerous studies with estimates ranging from 20 to 50% lower risk in the most versus the least active study participants. Underweight and obesity have also been associated with lower lung cancer risk, with a nonlinear, inverted U-shaped relationship. However, associations of physical activity and obesity with lung cancer are likely significantly confounded by smoking since individuals who smoke are generally less active and leaner than non-smokers, but few studies have examined these associations stratified by smoking status. Using data from 162,679 men and women who were cancer-free at enrollment (1992-1993) in the American Cancer Society Cancer Prevention Study-II Nutrition Cohort, we examined associations of baseline recreational physical activity (MET-hours per week; none, 0.1 to <8.75 (reference), 8.75-17.4, 17.5+ MET-hours/week), baseline body mass index (BMI, weight (kg)/height (m²); <18.5, 18.5-22.0 (reference), 22.1-24.9, 25.0-29.9, 30.0+ kg/m²), and waist circumference (measured in 1997; sex-specific quartiles) in relation to lung cancer risk stratified by smoking status and years since quitting among former smokers (never, current, former <10 years, former, 10-19 years, former 20+ years). Cox proportional hazards modeling computed hazard rate ratios (RR) and 95% confidence intervals (CI) while adjusting for potential confounders. During 2,384,546 person years of follow-up time, 4,669 men and women were diagnosed with lung cancer (453 among never smokers; 1,452 among current smokers; 1,194 among former smokers <10 years since quitting; 725 among former 10-19 years; and 845 among former 20+ years). Physical activity was not associated with lung cancer risk within any of the smoking strata except in former smokers less than 10 years since quitting (RR = 0.77; 95% CI 0.67-0.90 for 17.5+ MET-hours/week). Similarly, BMI was inversely associated with lung cancer in former smokers less than 10 years since quitting (RR = 0.68; 95% CI 0.55-0.84 for 30+ kg/m²) and more modestly in former smokers who quit 10-19 and 20+ years ago. Waist circumference was not associated with lung cancer risk in any smoking category. While being physically active and maintaining a healthy body weight are important for prevention of various chronic diseases, including several types of cancer, our results suggest that physical activity, BMI, and waist circumference are not associated with lung cancer risk, regardless of smoking status.

Visceral Obesity Is Associated with Gallbladder Polyps

Background/Aims

Gallbladder polyps (GBP) are a common clinical finding and may possess malignant potential. We conducted this study to determine whether visceral obesity is a risk factor for GBP.

Methods

We retrospectively reviewed records of subjects who received both ultrasonography and computed tomography with measurements of the areas of visceral adipose tissue and total adipose tissue (TAT) on the same day as health checkups.

Results

Ninety-three of 1,615 subjects (5.8%) had GBP and were compared with 186 age- and sex-matched controls. VAT (odds ratio [OR], 2.941; 95% confidence interval [CI], 1.325 to 6.529; p=0.008 for the highest quartile vs the lowest quartile) and TAT (OR, 3.568; 95% CI, 1.625 to 7.833; p=0.002 for the highest quartile vs the lowest quartile) were independent risk factors together with hypertension (OR, 2.512; 95% CI, 1.381 to 4.569; p=0.003), diabetes mellitus (OR, 2.942; 95% CI, 1.061 to 8.158; p=0.038), hepatitis B virus positivity (OR, 3.548; 95% CI, 1.295 to 9.716; p=0.014), and a higher level of total cholesterol (OR, 2.232; 95% CI, 1.043 to 4.778; p=0.039 for <200 mg/dL vs ≥240 mg/dL). Body mass index and waist circumference were not meaningful variables.

Conclusions

Visceral obesity measured by VAT and TAT was associated with GBP irrespective of body mass index or waist circumference.

Associations of Oral α-, β-, and γ-Human Papillomavirus Types With Risk of Incident Head and Neck Cancer

Importance

Prospective studies are needed to examine the temporal relationship between oral human papillomavirus (HPV) detection and risk of head and neck squamous cell carcinoma (HNSCC). Moreover, the oral cavity contains a wide spectrum of α-, β-, and γ-HPV types, but their association with risk of HNSCC is unknown.

Objective

To prospectively examine associations between α-, β-, and γ-HPV detection in the oral cavity and incident HNSCC.

Design

A nested case-control study was carried out among 96 650 participants, cancer free at baseline, with available mouthwash samples in 2 prospective cohort studies: (1) the American Cancer Society Cancer Prevention Study II Nutrition Cohort and (2) the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Incident cases of HNSCC (n = 132) were identified during an average 3.9 years of follow-up in both cohorts. Three controls per case (n = 396) were selected through incidence density sampling and matched on age, sex, race/ethnicity, and time since mouthwash collection.

Methods

Through a next-generation sequencing assay, DNA from α-, β-, and γ-HPV types were detected. Conditional logistic regression models were used to estimate odds ratios (ORs) and 95% CIs, adjusting for smoking history, alcohol consumption, and detection of HPV-16 for β- and γ-HPVs.

Main Outcomes and Measures

Incident HNSCC, which includes cancers of the oropharynx, oral cavity, and larynx.

Results

A total of 132 participants developed HNSCC during the follow-up period (103 men and 29 women; average age at baseline, 66.5 years). Oral HPV-16 detection was associated with incident HNSCC (OR, 7.1; 95% CI, 2.2-22.6), with positive association for oropharyngeal SCC (OR, 22.4; 95% CI, 1.8-276.7), but not for oral cavity (OR, 4.5; 95% CI, 0.6-34.7) or laryngeal SCCs (OR, 0.11; 95% CI, 0.01-834.80). Detection of β1-HPV-5 and β2-HPV-38 types, as well as γ-11 and γ-12 species, had ORs for HNSCC that ranged from 2.64 to 5.45 (P < .01 for all comparisons). Detection of β1-HPV-5 type was associated with oropharyngeal (OR, 7.42; 95% CI, 0.98-56.82; P = .054), oral cavity (OR, 5.34; 95% CI, 1.51-18.80; P = .01), and laryngeal SCCs (OR, 2.71; 95% CI, 1.00-7.43; P = .05), whereas γ11- and γ12-HPV species were associated with both oral cavity (OR, 7.47; 95% CI, 1.21-46.17; P = .03; and OR, 6.71; 95% CI, 1.47-30.75; P = .01, respectively) and laryngeal SCCs (OR, 7.49; 95% CI, 1.10-51.04; P = .04 and OR, 5.31; 95% CI, 1.13-24.95; P = .03, respectively).

Conclusions and Relevance

This study demonstrates that HPV-16 detection precedes the incidence of oropharyngeal SCC. Associations of other HPVs, including γ11- and γ12-HPV species and β1-HPV-5 type suggest a broader role for HPVs in HNSCC etiology.

Anthropometric Factors and Thyroid Cancer Risk by Histological Subtype: Pooled Analysis of 22 Prospective Studies

BACKGROUND

Greater height and body mass index (BMI) have been associated with an increased risk of thyroid cancer, particularly papillary carcinoma, the most common and least aggressive subtype. Few studies have evaluated these associations in relation to other, more aggressive histologic types or thyroid cancer-specific mortality.

METHODS

This large pooled analysis of 22 prospective studies (833,176 men and 1,260,871 women) investigated thyroid cancer incidence associated with greater height, BMI at baseline and young adulthood, and adulthood BMI gain (difference between young-adult and baseline BMI), overall and separately by sex and histological subtype using multivariable Cox proportional hazards regression models. Associations with thyroid cancer mortality were investigated in a subset of cohorts (578,922 men and 774,373 women) that contributed cause of death information.

RESULTS

During follow-up, 2996 incident thyroid cancers and 104 thyroid cancer deaths were identified. All anthropometric factors were positively associated with thyroid cancer incidence: hazard ratios (HR) [confidence intervals (CIs)] for height (per 5 cm) = 1.07 [1.04-1.10], BMI (per 5 kg/m2) = 1.06 [1.02-1.10], waist circumference (per 5 cm) = 1.03 [1.01-1.05], young-adult BMI (per 5 kg/m2) = 1.13 [1.02-1.25], and adulthood BMI gain (per 5 kg/m2) = 1.07 [1.00-1.15]. Associations for baseline BMI and waist circumference were attenuated after mutual adjustment. Baseline BMI was more strongly associated with risk in men compared with women (p = 0.04). Positive associations were observed for papillary, follicular, and anaplastic, but not medullary, thyroid carcinomas. Similar, but stronger, associations were observed for thyroid cancer mortality.

CONCLUSION

The results suggest that greater height and excess adiposity throughout adulthood are associated with higher incidence of most major types of thyroid cancer, including the least common but most aggressive form, anaplastic carcinoma, and higher thyroid cancer mortality. Potential underlying biological mechanisms should be explored in future studies.

Identification of shared and unique susceptibility pathways among cancers of the lung, breast, and prostate from genome-wide association studies and tissue-specific protein interactions

Results from genome-wide association studies (GWAS) have indicated that strong single-gene effects are the exception, not the rule, for most diseases. We assessed the joint effects of germline genetic variations through a pathway-based approach that considers the tissue-specific contexts of GWAS findings. From GWAS meta-analyses of lung cancer (12 160 cases/16 838 controls), breast cancer (15 748 cases/18 084 controls) and prostate cancer (14 160 cases/12 724 controls) in individuals of European ancestry, we determined the tissue-specific interaction networks of proteins expressed from genes that are likely to be affected by disease-associated variants. Reactome pathways exhibiting enrichment of proteins from each network were compared across the cancers. Our results show that pathways associated with all three cancers tend to be broad cellular processes required for growth and survival. Significant examples include the nerve growth factor (P = 7.86 × 10(-33)), epidermal growth factor (P = 1.18 × 10(-31)) and fibroblast growth factor (P = 2.47 × 10(-31)) signaling pathways. However, within these shared pathways, the genes that influence risk largely differ by cancer. Pathways found to be unique for a single cancer focus on more specific cellular functions, such as interleukin signaling in lung cancer (P = 1.69 × 10(-15)), apoptosis initiation by Bad in breast cancer (P = 3.14 × 10(-9)) and cellular responses to hypoxia in prostate cancer (P = 2.14 × 10(-9)). We present the largest comparative cross-cancer pathway analysis of GWAS to date. Our approach can also be applied to the study of inherited mechanisms underlying risk across multiple diseases in general.

Central adiposity, obesity during early adulthood, and pancreatic cancer mortality in a pooled analysis of cohort studies

BACKGROUND

Body mass index (BMI), a measure of obesity typically assessed in middle age or later, is known to be positively associated with pancreatic cancer. However, little evidence exists regarding the influence of central adiposity, a high BMI during early adulthood, and weight gain after early adulthood on pancreatic cancer risk.

DESIGN

We conducted a pooled analysis of individual-level data from 20 prospective cohort studies in the National Cancer Institute BMI and Mortality Cohort Consortium to examine the association of pancreatic cancer mortality with measures of central adiposity (e.g. waist circumference; n = 647 478; 1947 pancreatic cancer deaths), BMI during early adulthood (ages 18-21 years) and BMI change between early adulthood and cohort enrollment, mostly in middle age or later (n = 1 096 492; 3223 pancreatic cancer deaths). Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models.

RESULTS

Higher waist-to-hip ratio (HR = 1.09, 95% CI 1.02-1.17 per 0.1 increment) and waist circumference (HR = 1.07, 95% CI 1.00-1.14 per 10 cm) were associated with increased risk of pancreatic cancer mortality, even when adjusted for BMI at baseline. BMI during early adulthood was associated with increased pancreatic cancer mortality (HR = 1.18, 95% CI 1.11-1.25 per 5 kg/m(2)), with increased risk observed in both overweight and obese individuals (compared with BMI of 21.0 to <23 kg/m(2), HR = 1.36, 95% CI 1.20-1.55 for BMI 25.0 < 27.5 kg/m(2), HR = 1.48, 95% CI 1.20-1.84 for BMI 27.5 to <30 kg/m(2), HR = 1.43, 95% CI 1.11-1.85 for BMI ≥30 kg/m(2)). BMI gain after early adulthood, adjusted for early adult BMI, was less strongly associated with pancreatic cancer mortality (HR = 1.05, 95% CI 1.01-1.10 per 5 kg/m(2)).

CONCLUSIONS

Our results support an association between pancreatic cancer mortality and central obesity, independent of BMI, and also suggest that being overweight or obese during early adulthood may be important in influencing pancreatic cancer mortality risk later in life.

Alcohol consumption and breast cancer risk by estrogen receptor status: in a pooled analysis of 20 studies

BACKGROUND

Breast cancer aetiology may differ by estrogen receptor (ER) status. Associations of alcohol and folate intakes with risk of breast cancer defined by ER status were examined in pooled analyses of the primary data from 20 cohorts.

METHODS

During a maximum of 6-18 years of follow-up of 1 089 273 women, 21 624 ER+ and 5113 ER- breast cancers were identified. Study-specific multivariable relative risks (RRs) were calculated using Cox proportional hazards regression models and then combined using a random-effects model.

RESULTS

Alcohol consumption was positively associated with risk of ER+ and ER- breast cancer. The pooled multivariable RRs (95% confidence intervals) comparing ≥ 30 g/d with 0 g/day of alcohol consumption were 1.35 (1.23-1.48) for ER+ and 1.28 (1.10-1.49) for ER- breast cancer (Ptrend ≤ 0.001; Pcommon-effects by ER status: 0.57). Associations were similar for alcohol intake from beer, wine and liquor. The associations with alcohol intake did not vary significantly by total (from foods and supplements) folate intake (Pinteraction ≥ 0.26). Dietary (from foods only) and total folate intakes were not associated with risk of overall, ER+ and ER- breast cancer; pooled multivariable RRs ranged from 0.98 to 1.02 comparing extreme quintiles. Following-up US studies through only the period before mandatory folic acid fortification did not change the results. The alcohol and folate associations did not vary by tumour subtypes defined by progesterone receptor status.

CONCLUSIONS

Alcohol consumption was positively associated with risk of both ER+ and ER- breast cancer, even among women with high folate intake. Folate intake was not associated with breast cancer risk.

Improving the estimation of flavonoid intake for study of health outcomes

Imprecision in estimating intakes of non-nutrient bioactive compounds such as flavonoids is a challenge in epidemiologic studies of health outcomes. The sources of this imprecision, using flavonoids as an example, include the variability of bioactive compounds in foods due to differences in growing conditions and processing, the challenges in laboratory quantification of flavonoids in foods, the incompleteness of flavonoid food composition tables, and the lack of adequate dietary assessment instruments. Steps to improve databases of bioactive compounds and to increase the accuracy and precision of the estimation of bioactive compound intakes in studies of health benefits and outcomes are suggested.

Microbiome in reflux disorders and esophageal adenocarcinoma

The incidence of esophageal adenocarcinoma has increased dramatically in the United States and Europe since the 1970s without apparent cause. Although specific host factors can affect risk of disease, such a rapid increase in incidence must be predominantly environmental. In the stomach, infection with Helicobacter pylori has been linked to chronic atrophic gastritis, an inflammatory precursor of gastric adenocarcinoma. However, the role of H. pylori in the development of esophageal adenocarcinoma is not well established. Meanwhile, several studies have established that a complex microbiome in the distal esophagus might play a more direct role. Transformation of the microbiome in precursor states to esophageal adenocarcinoma-reflux esophagitis and Barrett metaplasia-from a predominance of gram-positive bacteria to mostly gram-negative bacteria raises the possibility that dysbiosis is contributing to pathogenesis. However, knowledge of the microbiome in esophageal adenocarcinoma itself is lacking. Microbiome studies open a new avenue to the understanding of the etiology and pathogenesis of reflux disorders.

Tobacco and alcohol in relation to male breast cancer: an analysis of the male breast cancer pooling project consortium

BACKGROUND

The etiology of male breast cancer is poorly understood, partly due to its relative rarity. Although tobacco and alcohol exposures are known carcinogens, their association with male breast cancer risk remains ill-defined.

METHODS

The Male Breast Cancer Pooling Project consortium provided 2,378 cases and 51,959 controls for analysis from 10 case-control and 10 cohort studies. Individual participant data were harmonized and pooled. Unconditional logistic regression was used to estimate study design-specific (case-control/cohort) ORs and 95% confidence intervals (CI), which were then combined using fixed-effects meta-analysis.

RESULTS

Cigarette smoking status, smoking pack-years, duration, intensity, and age at initiation were not associated with male breast cancer risk. Relations with cigar and pipe smoking, tobacco chewing, and snuff use were also null. Recent alcohol consumption and average grams of alcohol consumed per day were also not associated with risk; only one subanalysis of very high recent alcohol consumption (>60 g/day) was tentatively associated with male breast cancer (ORunexposed referent = 1.29; 95% CI, 0.97-1.71; OR>0-<7 g/day referent = 1.36; 95% CI, 1.04-1.77). Specific alcoholic beverage types were not associated with male breast cancer. Relations were not altered when stratified by age or body mass index.

CONCLUSIONS

In this analysis of the Male Breast Cancer Pooling Project, we found little evidence that tobacco and alcohol exposures were associated with risk of male breast cancer.

IMPACT

Tobacco and alcohol do not appear to be carcinogenic for male breast cancer. Future studies should aim to assess these exposures in relation to subtypes of male breast cancer.

Analysis of Multivariate Disease Classification Data in the Presence of Partially Missing Disease Traits

In modern cancer epidemiology, diseases are classified based on pathologic and molecular traits, and different combinations of these traits give rise to many disease subtypes. The effect of predictor variables can be measured by fitting a polytomous logistic model to such data. The differences (heterogeneity) among the relative risk parameters associated with subtypes are of great interest to better understand disease etiology. Due to the heterogeneity of the relative risk parameters, when a risk factor is changed, the prevalence of one subtype may change more than that of another subtype does. Estimation of the heterogeneity parameters is difficult when disease trait information is only partially observed and the number of disease subtypes is large. We consider a robust semiparametric approach based on the pseudo-conditional likelihood for estimating these heterogeneity parameters. Through simulation studies, we compare the robustness and efficiency of our approach with that of the maximum likelihood approach. The method is then applied to analyze the associations of weight gain with risk of breast cancer subtypes using data from the American Cancer Society Cancer Prevention Study II Nutrition Cohort.

A prospective study of alcohol consumption and renal cell carcinoma risk

Recent epidemiological studies suggest that alcohol consumption may reduce renal cell carcinoma (RCC) risk, although inconsistent findings have been reported by sex and alcoholic beverage type. To better understand the relationship between alcohol consumption and RCC risk, we conducted an analysis within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We followed up participants in the analytic cohort (N = 107,998) through 2010 for incident RCC (N = 408), and computed hazard ratios (HRs) and 95% confidence intervals (CIs) for alcohol intake using Cox regression with adjustment for age, sex, race, study center, hypertension, body mass index, and smoking status. In this study population increasing alcohol consumption was associated with reduced RCC risk compared to non-drinkers (>9.75 g day(-1) : HR, 0.67; 95%CI, 0.50 to 0.89; p trend = 0.002). We observed similar patterns of association for men and women as well as by alcohol beverage type. In analyses stratified by smoking status, the inverse association with consumption was apparent for ever smokers (HR, 0.51; 95%CI, 0.36 to 0.73; p trend<0.0001) but not among never smokers (HR, 1.08; 95%CI, 0.66 to 1.76; P trend = 0.78; p interaction = 0.01). Our study findings offer further support that alcohol consumption is associated with reduced RCC risk, regardless of sex or alcoholic beverage type. The finding of interaction with smoking is novel and requires confirmation.

Dietary ω-3 polyunsaturated fatty acid intake and risk for amyotrophic lateral sclerosis

IMPORTANCE

Amyotrophic lateral sclerosis (ALS) is a severe progressive disease that cannot be prevented or cured. Diet-derived long-chain polyunsaturated fatty acids (PUFAs) are incorporated in brain lipids and modulate oxidative and inflammatory processes and could thus affect ALS risk and progression.

OBJECTIVE

To examine the association between ω-6 and ω-3 PUFA consumption and ALS risk.

DESIGN, SETTING, AND PARTICIPANTS

Longitudinal analyses based on 1,002,082 participants (479,114 women and 522,968 men) in 5 prospective cohorts: the National Institutes of Health-AARP Diet and Health Study, the Cancer Prevention Study II Nutrition Cohort, the Health Professionals Follow-up Study, the Multiethnic Cohort Study, and the Nurses' Health Study. Diet was assessed via food frequency questionnaire developed or modified for each cohort. Participants were categorized into cohort-specific quintiles of intake of energy-adjusted dietary variables.

MAIN OUTCOMES AND MEASURES

Cohort-specific multivariable-adjusted risk ratios (RRs) of ALS incidence or death estimated by Cox proportional hazards regression and pooled using random-effects methods.

RESULTS

A total of 995 ALS cases were documented during the follow-up. A greater ω-3 PUFA intake was associated with a reduced risk for ALS. The pooled, multivariable-adjusted RR for the highest to the lowest quintile was 0.66 (95% CI, 0.53-0.81; P < .001 for trend). Consumption of both α-linolenic acid (RR, 0.73; 95% CI, 0.59-0.89; P = .003 for trend) and marine ω-3 PUFAs (RR, 0.84; 95% CI, 0.65-1.08; P = .03 for trend) contributed to this inverse association. Intakes of ω-6 PUFA were not associated with ALS risk.

CONCLUSIONS AND RELEVANCE

Consumption of foods high in ω-3 PUFAs may help prevent or delay the onset of ALS.