Recalibrating the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO) Environmental Risk Score for Use in US Veterans.

BACKGROUND: Risk for colorectal cancer (CRC) may accumulate through multiple environmental factors. Understanding their effects, along with genetics, age and family history, could allow improvements in clinical decisions for screening protocols. We aimed to extend previous work by recalibrating an environmental risk score (e-Score) for CRC among a sample of US Veteran participants of the Million Veteran Program (MVP). METHODS: Demographic, lifestyle, and CRC data from 2011-2022 were abstracted from survey responses and health records of 227,504 male MVP participants. Weighting for each environmental factor's effect size was recalculated using VA training data to create a recalibrated e-Score. This recalibrated score was compared with the original weighted e-Score in a validation sample of 113,752 (n cases=590). Nested multiple logistic regression models tested associations between quintiles for recalibrated and original e-Scores. Likelihood Ratio Tests were used to compare model performance. RESULTS: Age (p<0.0001), education (p<0.0001), diabetes (p<0.0001), physical activity (p<0.0001), smoking (p<0.0001), NSAID use (p<0.0001), calcium (p=0.015), folate (p=0.020), and fruit consumption (p=0.019) were significantly different between CRC case and control groups. In the validation sample, the recalibrated e-Score model significantly improved the base model performance (p<0.001), but the original e-Score model did not (p=0.07). The recalibrated e-Score model quintile 5 was associated with significantly higher odds for CRC compared with quintile 1 (Q5 vs Q1: 1.79, 95% CI: 1.38-2.33). CONCLUSIONS: Multiple environmental factors, and the recalibrated e-Score quintiles were significantly associated with CRC cases. IMPACT: A recalibrated, Veteran-specific e-Score could be used to help personalize CRC screening and prevention strategies.

Colorectal Cancer Polygenic Risk Score Is Associated With Screening Colonoscopy Findings but Not Follow-Up Outcomes.

Background and Aims: Colorectal cancer (CRC) polygenic risk scores (PRS) may help personalize CRC prevention strategies. We investigated whether an existing PRS was associated with advanced neoplasia (AN) in a population undergoing screening and follow-up colonoscopy. Methods: We evaluated 10-year outcomes in the Cooperative Studies Program #380 screening colonoscopy cohort, which includes a biorepository of selected individuals with baseline AN (defined as CRC or adenoma ≥10 mm or villous histology, or high-grade dysplasia) and matched individuals without AN. A PRS was constructed from 136 prespecified CRC-risk single nucleotide polymorphisms. Multivariate logistic regression was used to evaluate the PRS for associations with AN prevalence at baseline screening colonoscopy or incident AN in participants with at least one follow-up colonoscopy. Results: The PRS was associated with AN risk at baseline screening colonoscopy (P = .004). Participants in the lowest PRS quintile had more than a 70% decreased risk of AN at baseline (odds ratio 0.29, 95% confidence interval 0.14-0.58; P < .001) compared to participants with a PRS in the middle quintile. Using a PRS cut-off of more than the first quintile to indicate need for colonoscopy as primary screening, the sensitivity for detecting AN at baseline is 91.8%. We did not observe a relationship between the PRS and incident AN during follow-up (P = .28). Conclusion: A PRS could identify individuals at low risk for prevalent AN. Ongoing work will determine whether this PRS can identify a subset of individuals at sufficiently low risk who could safely delay or be reassured about noninvasive screening. Otherwise, more research is needed to augment these genetic tools to predict incident AN during long-term follow-up.

Longitudinal assessment of colonoscopy adverse events in the prospective Cooperative Studies Program no. 380 colorectal cancer screening and surveillance cohort.

BACKGROUND AND AIMS: Data are limited regarding colonoscopy risk during long-term, programmatic colorectal cancer screening and follow-up. We aimed to describe adverse events during follow-up in a colonoscopy screening program after the baseline examination and examine factors associated with increased risk. METHODS: Cooperative Studies Program no. 380 includes 3121 asymptomatic veterans aged 50 to 75 years who underwent screening colonoscopy between 1994 and 1997. Periprocedure adverse events requiring significant intervention were defined as major events (other events were minor) and were tracked during follow-up for at least 10 years. Multivariable odds ratios (ORs) were calculated for factors associated with risk of follow-up adverse events. RESULTS: Of 3727 follow-up examinations in 1983 participants, adverse events occurred in 105 examinations (2.8%) in 93 individuals, including 22 major and 87 minor events (examinations may have had >1 event). Incidence of major events (per 1000 examinations) remained relatively stable over time, with 6.1 events at examination 2, 4.8 at examination 3, and 7.2 at examination 4. Examinations with major events included 1 perforation, 3 GI bleeds requiring intervention, and 17 cardiopulmonary events. History of prior colonoscopic adverse events was associated with increased risk of events (major or minor) during follow-up (OR, 2.7; 95% confidence interval, 1.6-4.6). CONCLUSIONS: Long-term programmatic screening and surveillance was safe, as major events were rare during follow-up. However, serious cardiopulmonary events were the most common major events. These results highlight the need for detailed assessments of comorbid conditions during routine clinical practice, which could help inform individual decisions regarding the utility of ongoing colonoscopy follow-up.

Screening Colonoscopy Findings Are Associated With Noncolorectal Cancer Mortality.

INTRODUCTION: Controversy exists regarding the impact of various risk factors on noncolorectal cancer (CRC) mortality in healthy screening populations. We examined the impact of known CRC risk factors, including baseline colonoscopy findings, on non-CRC mortality in a screening population. METHODS: Cooperative Studies Program (CSP) #380 is comprised of 3,121 veterans aged 50-75 years who underwent screening colonoscopy from 1994 to 97 and were then followed for at least 10 years or until death. Hazard ratios (HRs) for risk factors on non-CRC mortality were estimated by multivariate Cox proportional hazards. RESULTS: Current smoking (HR 2.12, 95% confidence interval [CI] 1.78-2.52, compared with nonsmokers) and physical activity (HR 0.89, 95% CI 0.84-0.93) were the modifiable factors most associated with non-CRC mortality in CSP#380. In addition, compared with no neoplasia at baseline colonoscopy, non-CRC mortality was higher in participants with ≥3 small adenomas (HR 1.43, 95% CI 1.06-1.94), advanced adenomas (HR 1.32, 95% CI 0.99-1.75), and CRC (HR 2.95, 95% CI 0.98-8.85). Those with 1-2 small adenomas were not at increased risk for non-CRC mortality (HR 1.15, 95% CI 0.94-1.4). DISCUSSION: In a CRC screening population, known modifiable risk factors were significantly associated with 10-year non-CRC mortality. Furthermore, those who died from non-CRC causes within 10 years were more likely to have had high-risk findings at baseline colonoscopy. These results suggest that advanced colonoscopy findings may be a risk marker of poor health outcomes. Integrated efforts are needed to motivate healthy lifestyle changes during CRC screening, particularly in those with high-risk colonoscopy findings and unaddressed risk factors.

Ten or More Cumulative Lifetime Adenomas Are Associated with Increased Risk for Advanced Neoplasia and Colorectal Cancer.

BACKGROUND: Colorectal cancer (CRC) screening guidelines recommend frequent colonoscopies and consideration of genetic testing in individuals with ≥10 cumulative adenomas. However, it is unclear how these guidelines apply to routine practice. AIMS: We estimated the proportion of participants found to have ≥10 cumulative adenomas in a screening population and described their outcomes of advanced neoplasia (AN), CRC, and extra-colonic malignancy. METHODS: We performed a secondary analysis of VA CSP#380, which includes 3121 veterans aged 50-75 who were followed up to 10 years after screening colonoscopy. We calculated the cumulative risk of ≥10 cumulative adenomas by Kaplan-Meier method. We compared baseline risk factors in those with and without ≥10 cumulative adenomas as well as the risk for AN (adenoma ≥1 cm, villous adenoma or high-grade dysplasia, or CRC) and extra-colonic malignancy by multivariate logistic regression. RESULTS: The cumulative risk of ≥10 cumulative adenomas over 10.5 years was 6.51% (95% CI 4.38%-9.62%). Age 60-69 or 70-75 at baseline colonoscopy was the only factors associated with the finding of ≥10 cumulative adenomas. Compared to those with 0-9 cumulative adenomas, participants with ≥10 cumulative adenomas were more likely to have had AN (OR 17.03; 95% CI 9.41-30.84), including CRC (OR 7.00; 95% CI 2.84-17.28), but not extra-colonic malignancies. CONCLUSIONS: Approximately 6.5% of participants in this screening population were found to have ≥10 cumulative adenomas over 10.5 years, which was uncommon before age 60. These participants were found to have AN and CRC significantly more often compared to those with lower cumulative adenomas.

COVID-19-Associated Mortality in US Veterans with and without SARS-CoV-2 Infection.

BACKGROUND: We performed an observational Veterans Health Administration cohort analysis to assess how risk factors affect 30-day mortality in SARS-CoV-2-infected subjects relative to those uninfected. While the risk factors for coronavirus disease 2019 (COVID-19) have been extensively studied, these have been seldom compared with uninfected referents. METHODS: We analyzed 341,166 White/Black male veterans tested for SARS-CoV-2 from March 1 to September 10, 2020. The relative risk of 30-day mortality was computed for age, race, ethnicity, BMI, smoking status, and alcohol use disorder in infected and uninfected subjects separately. The difference in relative risk was then evaluated between infected and uninfected subjects. All the analyses were performed considering clinical confounders. RESULTS: In this cohort, 7% were SARS-CoV-2-positive. Age >60 and overweight/obesity were associated with a dose-related increased mortality risk among infected patients relative to those uninfected. In contrast, relative to never smoking, current smoking was associated with a decreased mortality among infected and an increased mortality in uninfected, yielding a reduced mortality risk among infected relative to uninfected. Alcohol use disorder was also associated with decreased mortality risk in infected relative to the uninfected. CONCLUSIONS: Age, BMI, smoking, and alcohol use disorder affect 30-day mortality in SARS-CoV-2-infected subjects differently from uninfected referents. Advanced age and overweight/obesity were associated with increased mortality risk among infected men, while current smoking and alcohol use disorder were associated with lower mortality risk among infected men, when compared with those uninfected.

Characterizing chronological accumulation of comorbidities in healthy veterans: a computational approach.

Understanding patient accumulation of comorbidities can facilitate healthcare strategy and personalized preventative care. We applied a directed network graph to electronic health record (EHR) data and characterized comorbidities in a cohort of healthy veterans undergoing screening colonoscopy. The Veterans Affairs Cooperative Studies Program #380 was a prospective longitudinal study of screening and surveillance colonoscopy. We identified initial instances of three-digit ICD-9 diagnoses for participants with at least 5 years of linked EHR history (October 1999 to December 2015). For diagnoses affecting at least 10% of patients, we calculated pairwise chronological relative risk (RR). iGraph was used to produce directed graphs of comorbidities with RR > 1, as well as summary statistics, key diseases, and communities. A directed graph based on 2210 patients visualized longitudinal development of comorbidities. Top hub (preceding) diseases included ischemic heart disease, inflammatory and toxic neuropathy, and diabetes. Top authority (subsequent) diagnoses were acute kidney failure and hypertensive chronic kidney failure. Four communities of correlated comorbidities were identified. Close analysis of top hub and authority diagnoses demonstrated known relationships, correlated sequelae, and novel hypotheses. Directed network graphs portray chronologic comorbidity relationships. We identified relationships between comorbid diagnoses in this aging veteran cohort. This may direct healthcare prioritization and personalized care.

Development of a Multi-Study Repository to Support Research on Veteran Health: The VA Cooperative Studies Program Epidemiology Center-Durham (CSPEC-Durham) Data and Specimen Repository.

Federal agencies, including the Department of Veterans Affairs (VA), have prioritized improved access to scientific data and results collected through federally funded research. Our VA Cooperative Studies Program Epidemiology Center in Durham, North Carolina (CSPEC-Durham) assembled a repository of data and specimens collected through multiple studies on Veteran health issues to facilitate future research in these areas. We developed a single protocol, request process that includes scientific and ethical review of all applications, and a database architecture using metadata (common variable descriptors) to securely store and share data across diverse studies. In addition, we created a mechanism to allow data and specimens collected through older studies in which re-use was not addressed in the study protocol or consent forms to be shared if the future research is within the scope of the original consent. Our CSPEC-Durham Data and Specimen Repository currently includes research data, genomic data, and study specimens (e.g., DNA, blood) for three content areas: colorectal cancer, amyotrophic lateral sclerosis, and Gulf War research. The linking of the study specimens and research data can support additional genetic analyses and related research to improve Veterans' health.

Genetic Colorectal Cancer and Adenoma Risk Variants Are Associated with Increasing Cumulative Adenoma Counts.

BACKGROUND: The genetic basis for most individuals with high cumulative lifetime colonic adenomas is unknown. We investigated associations between known colorectal cancer-risk single-nucleotide polymorphisms (SNP) and increasing cumulative adenoma counts. METHODS: The Cooperative Studies Program #380 screening colonoscopy cohort includes 612 selected participants age 50 to 75 with genotyped blood samples and 10 years of clinical follow-up. We evaluated 41 published "colorectal cancer-risk SNPs" for associations with individual cumulative adenoma counts or having ≥10 cumulative adenomas. SNPs were analyzed singly or combined in a polygenic risk score (PRS). The PRS was constructed from eight published SNPs associated with multiple adenomas, termed "adenoma-risk SNPs." RESULTS: Four colorectal cancer-risk SNPs were associated with increasing cumulative adenoma counts (P < 0.05): rs12241008 (gene: VTI1A), rs2423279 (BMP2/HAO1), rs3184504 (SH2B3), and rs961253 (FERMT1/BMP2), with risk allele risk ratios of 1.31, 1.29, 1.24, and 1.23, respectively. Three colorectal cancer-risk SNPs were associated with ≥10 cumulative adenomas (P < 0.05), with risk allele odds ratios of 2.09 (rs3184504), 2.30 (rs961253), and 1.94 (rs3217901). A weighted PRS comprised of adenoma-risk SNPs was associated with higher cumulative adenomas (weighted rate ratio = 1.57; P = 0.03). CONCLUSIONS: In this mostly male veteran colorectal cancer screening cohort, several known colorectal cancer-risk SNPs were associated with increasing cumulative adenoma counts and the finding of ≥10 cumulative adenomas. In addition, an increasing burden of adenoma-risk SNPs, measured by a weighted PRS, was associated with higher cumulative adenomas. IMPACT: Future work will seek to validate these findings in different populations and then augment current colorectal cancer risk prediction tools with precancerous, adenoma genetic data.

High-Risk Adenomas at Screening Colonoscopy Remain Predictive of Future High-Risk Adenomas Despite an Intervening Negative Colonoscopy.

INTRODUCTION: Limited data inform the current postpolypectomy surveillance guidelines, which suggest a shortened interval to third colonoscopy after a negative second examination if high-risk adenomas (HRA) were present on the initial screening colonoscopy. Therefore, we examined the risk of HRA at third colonoscopy stratified by findings on 2 previous examinations in a prospective screening colonoscopy cohort of US veterans. METHODS: We identified participants who had 3 or more colonoscopies from CSP#380. We examined the risk of HRA on the third examination based on findings from the previous 2 examinations. Multivariate logistic regression was used to adjust for multiple covariates. RESULTS: HRA were found at the third examination in 114 (12.8%) of 891 participants. Those with HRA on both previous examinations had the greatest incidence of HRA at third examination (14/56, 25.0%). Compared with those with no adenomas on both previous examinations, participants with HRA on the first examination remained at significantly increased risk for HRA at the third examination at 3 years after a negative second examination (odds ratio [OR] 3.41, 95% confidence interval [CI] 1.28-9.08), 5 years (OR 3.14, 95% CI 1.49-6.61), and 7 years (OR 2.89, 95% CI 1.08-7.74). DISCUSSION: In a screening population, HRA on the first examination identified individuals who remained at increased risk for HRA at the third examination, even after a negative second examination. This finding supports current colorectal cancer surveillance guidelines, which suggest a shortened, 5-year time interval to third colonoscopy after a negative second examination if high-risk findings were present on the baseline examination.

Baseline Colonoscopy Findings Associated With 10-Year Outcomes in a Screening Cohort Undergoing Colonoscopy Surveillance.

BACKGROUND & AIMS: Few studies have evaluated long-term outcomes of ongoing colonoscopic screening and surveillance in a screening population. We aimed to determine the 10-year risk for advanced neoplasia (defined as adenomas ≥10mm, adenomas with villous histology or high-grade dysplasia, or colorectal cancer [CRC]) and assessed whether baseline colonoscopy findings were associated with long-term outcomes. METHODS: We collected data from the Department of Veterans Affairs Cooperative Studies Program Study on 3121 asymptomatic veterans (50-75 years old) who underwent a screening colonoscopy from 1994 through 1997 at 13 medical centers and were then followed for 10 years or until death. We included 1915 subjects with at least 1 surveillance colonoscopy and estimated cumulative incidence of advanced neoplasia by Kaplan-Meier curves. We then fit a longitudinal joint model to estimate risk of advanced neoplasia at each subsequent examination after baseline, adjusting for multiple colonoscopies within individuals. RESULTS: Through 10 years of follow-up, there were 146 individuals among all baseline colonoscopy groups found to have at least 1 incident advanced neoplasia. The cumulative 10-year incidence of advanced neoplasia was highest among those with baseline CRC (43.7%; 95% CI 13.0%-74.4%), followed by those with baseline advanced adenoma (AA) (21.9%; 95% CI 15.7-28.1). The cumulative 10-year incidence of advanced neoplasia was 6.3% (95% CI 4.1%-8.5%) and 4.1% (95% CI 2.7%-5.4%) for baseline 1 to 2 small adenomas (<1cm, and without villous histology or high-grade dysplasia) and no neoplasia, respectively (log-rank P = .10). After adjusting for prior surveillance, the risk of advanced neoplasia at each subsequent examination was not significantly increased in veterans with 1 or 2 small adenomas at baseline (odds ratio 0.96; 95% CI 0.67-1.41) compared with veterans with no baseline neoplasia. CONCLUSIONS: Baseline screening colonoscopy findings associate with advanced neoplasia within 10 years. Individuals with only 1 or 2 small adenomas at baseline have a low risk of advanced neoplasia over 10 years. Alternative surveillance strategies, could be considered for these individuals.

Racial Differences in Treatment and Survival among Veterans and Non-Veterans with Stage I NSCLC: An Evaluation of Veterans Affairs and SEER-Medicare Populations.

BACKGROUND: Surgery is the preferred treatment for stage I non-small cell lung cancer (NSCLC), with radiation reserved for those not receiving surgery. Previous studies have shown lower rates of surgery among Blacks with stage I NSCLC than among Whites. METHODS: Black and White men ages ≥65 years with stage I NSCLC diagnosed between 2001 and 2009 were identified in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database and Veterans Affairs (VA) cancer registry. Logistic regression and Cox proportional hazards models were used to examine associations between race, treatment, and survival. RESULTS: Among the patients in the VA (n = 7,895) and SEER (n = 8,744), the proportion of Blacks was 13% and 7%, respectively. Overall, 16.2% of SEER patients (15.4% of Whites, 26.0% of Blacks) and 24.5% of VA patients received no treatment (23.4% of Whites, 31.4% of Blacks). In both cohorts, Blacks were less likely to receive any treatment compared with Whites [ORadj = 0.57; 95% confidence interval (CI), 0.47-0.69 for SEER-Medicare; ORadj = 0.68; 95% CI, 0.58-0.79 for VA]. Among treated patients, Blacks were less likely than Whites to receive surgery only (ORadj = 0.57; 95% CI, 0.47-0.70 for SEER-Medicare; ORadj = 0.73; 95% CI, 0.62-0.86 for VA), but more likely to receive chemotherapy only and radiation only. There were no racial differences in survival. CONCLUSIONS: Among VA and SEER-Medicare patients, Blacks were less likely to get surgical treatment. Blacks and Whites had similar survival outcomes when accounting for treatment. IMPACT: This supports the hypothesis that equal treatment correlates with equal outcomes and emphasizes the need to understand multilevel predictors of lung cancer treatment disparities.

Advanced neoplasia in Veterans at screening colonoscopy using the National Cancer Institute Risk Assessment Tool.

BACKGROUND: Adapting screening strategy to colorectal cancer (CRC) risk may improve efficiency for all stakeholders however limited tools for such risk stratification exist. Colorectal cancers usually evolve from advanced neoplasms that are present for years. We applied the National Cancer Institute (NCI) CRC Risk Assessment Tool, which calculates future risk of CRC, to determine whether it could be used to predict current advanced neoplasia (AN) in a veteran cohort undergoing a baseline screening colonoscopy. METHODS: This was a prospective assessment of the relationship between future CRC risk predicted by the NCI tool, and the presence of AN at screening colonoscopy. Family, medical, dietary and physical activity histories were collected at the time of screening colonoscopy and used to calculate absolute CRC risk at 5, 10 and 20 years. Discriminatory accuracy was assessed. RESULTS: Of 3121 veterans undergoing screening colonoscopy, 94% had complete data available to calculate risk (N = 2934, median age 63 years, 100% men, and 15% minorities). Prevalence of AN at baseline screening colonoscopy was 11 % (N = 313). For tertiles of estimated absolute CRC risk at 5 years, AN prevalences were 6.54% (95% CI, 4.99, 8.09), 11.26% (95% CI, 9.28-13.24), and 14.21% (95% CI, 12.02-16.40). For tertiles of estimated risk at 10 years, the prevalences were 6.34% (95% CI, 4.81-7.87), 11.25% (95% CI, 9.27-13.23), and 14.42% (95% CI, 12.22-16.62). For tertiles of estimated absolute CRC risk at 20 years, current AN prevalences were 7.54% (95% CI, 5.75-9.33), 10.53% (95% CI, 8.45-12.61), and 12.44% (95% CI, 10.2-14.68). The area under the curve for predicting current AN was 0.60 (95% CI; 0.57-0.63, p < 0.0001) at 5 years, 0.60 (95% CI, 0.57-0.63, p < 0.0001) at 10 years and 0.58 (95% CI, 0.54-0.61, p < 0.0001) at 20 years. CONCLUSION: The NCI tool had modest discriminatory function for estimating the presence of current advanced neoplasia in veterans undergoing a first screening colonoscopy. These findings are comparable to other clinically utilized cancer risk prediction models and may be used to inform the benefit-risk assessment of screening, particularly for patients with competing comorbidities and lower risk, for whom a non-invasive screening approach is preferred.

Racial/Ethnic Disparities in BRCA Counseling and Testing: a Narrative Review.

BACKGROUND/OBJECTIVE: Despite increases in BRCA mutation testing, racial/ethnic disparities in counseling and testing have persisted for decades. The purpose of the review was to summarize recent literature as it relates to detecting, understanding, and reducing disparities in BRCA counseling and testing. DESIGN: This is a narrative review of articles published January 2012 to July 2017 relevant to genetic testing and counseling, breast and ovarian cancer, and minority health and heath disparities. Twenty-three articles were included in this review. RESULTS: Studies report lower counseling and/or testing rates for eligible racial/ethnic minorities among family members of high-risk individuals as well as among breast cancer survivors. Key barriers and facilitators of disparate BRCA counseling/testing that emerged in this review included awareness, cost-related factors, stress and distrust, family concerns and communication, and provider communication and referral. To address differential access to and use of BRCA testing services and expand testing in minority populations, it is necessary for interventions to focus on improving awareness, risk-perception, and family and patient-provider communication. CONCLUSION: Multi-level and targeted interventions are needed to reduce persistent racial/ethnic disparities and improve assessment, provider recommendations, counseling and testing among minority populations.