Kidney Cancer Incidence Among Non-Hispanic American Indian and Alaska Native Populations in the United States, 1999-2020.

Background Non-Hispanic American Indian and Alaska Native (NH-AI/AN) people experience a disproportionate incidence of kidney cancer. Nationally aggregated data does not allow for a comprehensive description of regional disparities in kidney cancer incidence among NH-AI/AN communities. This study describes kidney cancer incidence rates and trends among NH-AI/AN compared to non-Hispanic White (NHW) populations by geographic region. Methods Using the United States Cancer Statistics American Indian and Alaska Native (AI/AN) Incidence Analytic Database, we calculated age-adjusted incidence rates (per 100,000) of kidney cancers for NH-AI/AN and NHW people for the years 2011-2020 combined using SEER*stat software. Analyses were restricted to non-Hispanic persons living in purchased/referred care delivery area (PRCDA) counties. Average annual percent changes (AAPCs) and trends (1999-2019) were estimated using Joinpoint regression analyses. Results Rates of kidney cancer incidence were higher among NH-AI/AN compared to NHW persons in the U.S. overall and in 5 of 6 regions. Kidney cancer incidence rates also varied by region, sex, age, and stage of diagnosis. Between 1999 and 2019, trends in rates of kidney cancer significantly increased among NH-AI/AN males (AAPC = 2.7%) and females (AAPC = 2.4%). The largest increases in incidence were observed for NH-AI/AN males and females under age 50 and those diagnosed with localized stage disease. Conclusions Study findings highlight growing disparities in kidney cancer incidence rates between NH-AI/AN and NHW populations. Impact: Differences in geographic region, sex, and stage highlight opportunities to decrease prevalence of kidney cancer risk factors and improve access to preventive care.

Incidence of Stomach, Liver, and Colorectal Cancers by Geography and Social Vulnerability Among American Indian and Alaska Native Populations, 2010-2019.

Social determinants of health and associated systems, policies, and practices are important drivers of health disparities. American Indian and Alaska Native (AI/AN) populations in the United States have elevated incidence rates of stomach, liver, and colorectal cancers compared with other racial/ethnic groups. In this study, we examined incidence rates of 3 types of gastrointestinal cancer among non-Hispanic AI/AN (NH-AI/AN) and non-Hispanic White (NHW) populations by geographic region and Social Vulnerability Index (SVI) score. Incident cases diagnosed during 2010-2019 were identified from population-based cancer registries linked with the Indian Health Service patient registration databases. Age-adjusted incidence rates (per 100,000 population) for stomach, liver, and colorectal cancers were compared within NH-AI/AN populations and between the NH-AI/AN and NHW populations by SVI score. Rates were higher among NH-AI/AN populations in moderate- and high-SVI-score counties in Alaska, the Southern Plains, and the East than in low-SVI counties. Incidence rates among NH-AI/AN populations were elevated when compared with NHW populations by SVI category. Results indicated that higher social vulnerability may drive elevated cancer incidence among NH-AI/AN populations. Additionally, disparities between NH-AI/AN and NHW populations persist even when accounting for SVI. Exploring social vulnerability can aid in designing more effective interventions to address root causes of cancer disparities among AI/AN populations.

Disparities in incidence and trends of colorectal, lung, female breast, and cervical cancers among non-Hispanic American Indian and Alaska Native people, 1999-2018.

PURPOSE: This study is the first to comprehensively describe incidence rates and trends of screening-amenable cancers (colorectal, lung, female breast, and cervical) among non-Hispanic AI/AN (NH-AI/AN) people. METHODS: Using the United States Cancer Statistics AI/AN Incidence Analytic Database, we, calculated incidence rates for colorectal, lung, female breast, and cervical cancers for NH-AI/AN and non-Hispanic White (NHW) people for the years 2014-2018 combined. We calculated age-adjusted incidence rates (per 100,000), total percent change in incidence rates between 1999 and 2018, and trends over this time-period using Joinpoint analysis. Screening prevalence by region was calculated using Behavioral Risk Factor Surveillance System data. RESULTS: Rates of screening-amenable cancers among NH-AI/AN people varied by geographic region and age at diagnosis. Over half of all lung and colorectal cancers in NH-AI/AN people were diagnosed at later stages. Rates of lung and colorectal cancers decreased significantly between 1999-2018 among NH-AI/AN men, but no significant changes were observed in rates of screening-amenable cancers among NH-AI/AN women. CONCLUSION: This study highlights disparities in screening-amenable cancers between NH-AI/AN and NHW people. Culturally informed, community-based interventions that increase access to preventive health services could reduce cancer disparities among AI/AN people.

Elevated colorectal cancer incidence among American Indian/Alaska Native persons in Alaska compared to other populations worldwide.

Colorectal cancer (CRC) is a leading cancer worldwide; incidence varies greatly by country and racial group. We compared 2018 American Indian/Alaska Native (AI/AN) CRC incidence rates in Alaska to other Tribal, racial, and international population rates. AI/AN persons in Alaska had the highest CRC incidence rate among US Tribal and racial groups (61.9/100,000 in 2018). AI/AN persons in Alaska also had higher rates than those reported for any other country in the world in 2018 except for Hungary, where males had a higher CRC incidence rate than AI/AN males in Alaska (70.6/100,000 and 63.6/100,000 respectively). This review of CRC incidence rates from populations in the United States and worldwide showed that AI/AN persons in Alaska had the highest documented incidence rate of CRC in the world in 2018. It is important to inform health systems serving AI/AN persons in Alaska about policies and interventions that can support CRC screening to reduce the burden of this disease.

Cancer disparities among non-Hispanic urban American Indian and Alaska Native populations in the United States, 1999-2017.

BACKGROUND: Disparities in cancer incidence have not been described for urban American Indian/Alaska Native (AI/AN) populations. The purpose of the present study was to examine incidence rates (2008-2017) and trends (1999-2017) for leading cancers in urban non-Hispanic AI/AN (NH AI/AN) compared to non-Hispanic White (NHW) populations living in the same urban areas. METHODS: Incident cases from population-based cancer registries were linked with the Indian Health Service patient registration database for improved racial classification of NH AI/AN populations. This study was limited to counties in Urban Indian Health Organization service areas. Analyses were conducted by geographic region. Age-adjusted rates (per 100,000) and trends (joinpoint regression) were calculated for leading cancers. RESULTS: Rates of colorectal, liver, and kidney cancers were higher overall for urban NH AI/AN compared to urban NHW populations. By region, rates of these cancers were 10% to nearly 4 times higher in NH AI/AN compared to NHW populations. Rates for breast, prostate, and lung cancer were lower in urban NH AI/AN compared to urban NHW populations. Incidence rates for kidney, liver, pancreatic, and breast cancers increased from 2% to nearly 7% annually between 1999 to 2017 in urban NH AI/AN populations. CONCLUSIONS: This study presents cancer incidence rates and trends for the leading cancers among urban NH AI/AN compared to urban NHW populations for the first time, by region, in the United States. Elevated risk of certain cancers among urban NH AI/AN populations and widening cancer disparities highlight important health inequities and missed opportunities for cancer prevention in this population.

Growing Disparity in the Incidence of Colorectal Cancer among Non-Hispanic American Indian and Alaska Native Populations-United States, 2013-2017.

BACKGROUND: American Indian and Alaska Native (AI/AN) populations have experienced regional variation and disparities in colorectal cancer incidence rates. METHODS: We examined colorectal cancer incidence (2013-2017) and colorectal cancer incidence trends (1999-2017) among AI/AN persons. Incidence data were linked to Indian Health Service enrollment records, and analyses were restricted to Purchased/Referred Care Delivery Areas. Incidence rates of colorectal cancer among AI/AN and White persons were analyzed in six geographic regions; Hispanic persons were excluded. Incidence trends were analyzed using linear modeling. RESULTS: During 2013-2017, colorectal cancer incidence was 41% higher among AI/AN than among White persons. AI/AN incidence rates per 100,000 varied regionally from 34.4 in the East to 96.1 in Alaska. Compared with White persons, AI/AN persons had higher colorectal cancer incidence rates among all age strata and were more likely to have late-stage diagnoses. Incidence rate trends indicated significant increases among both AI/AN and White persons ages <50 years and among AI/AN persons ages 50-64 years. The colorectal cancer incidence rate trend increased among AI/AN persons in the Southwest. CONCLUSIONS: The disparity of colorectal cancer incidence rates between AI/AN and White persons has widened since 2005-2009. AI/AN populations have higher colorectal cancer incidence compared with White populations, especially in the Alaska region. IMPACT: Our finding of increased colorectal cancer incidence disparities suggests that enhanced screening efforts and culturally appropriate clinical and public health interventions are needed among AI/AN persons overall, and especially in regions and age groups in which colorectal cancer rates are increasing.

Incidence of and Trends in the Leading Cancers With Elevated Incidence Among American Indian and Alaska Native Populations, 2012-2016.

Cancer incidence varies among American Indian and Alaska Native (AI/AN) populations, as well as between AI/AN and White populations. This study examined trends for cancers with elevated incidence among AI/AN compared with non-Hispanic White populations and estimated potentially avoidable incident cases among AI/AN populations. Incident cases diagnosed during 2012-2016 were identified from population-based cancer registries and linked with the Indian Health Service patient registration databases to improve racial classification of AI/AN populations. Age-adjusted rates (per 100,000) and trends were calculated for cancers with elevated incidence among AI/AN compared with non-Hispanic White populations (rate ratio of >1.0) according to region. Trends were estimated using joinpoint regression analyses. Expected cancers were estimated by applying age-specific cancer incidence rates among non-Hispanic White populations to population estimates for AI/AN populations. Excess cancer cases among AI/AN populations were defined as observed minus expected cases. Liver, stomach, kidney, lung, colorectal, and female breast cancers had higher incidence rates among AI/AN populations across most regions. Between 2012 and 2016, nearly 5,200 excess cancers were diagnosed among AI/AN populations, with the largest number of excess cancers (1,925) occurring in the Southern Plains region. Culturally informed efforts could reduce cancer disparities associated with these and other cancers among AI/AN populations.

Gastric Cancer Among American Indian and Alaska Native Populations in the United States, 2005-2016.

INTRODUCTION: American Indian and Alaska Native (AI/AN) populations have higher gastric cancer rates than the general US population. This study provides a comprehensive overview of incidence rates among AI/AN persons during 2005-2016 compared with non-Hispanic whites (whites). METHODS: Population-based cancer registry data for 2005-2016 were linked with the Indian Health Service patient registration databases to address racial misclassification. Age-adjusted gastric cancer incidence rates were expressed per 100,000 per year. Incidence and trend analyses were restricted to purchased/referred care delivery area counties in 6 geographic regions, comparing gastric cancer incidence rates for AI/AN vs white populations in the United States. RESULTS: Gastric cancer rates were higher in the AI/AN compared with white populations in nearly every US region. Incidence rates for central/distal portions of the stomach were higher in AI/AN individuals compared with whites. Rates of later stage gastric cancer were higher in AI/AN populations overall and in every region except the Pacific Coast and East. Incidence rates decreased significantly over time in both populations. Declining rates in the AI/AN populations were driven by changes in the Pacific Coast and Northern Plains regions. DISCUSSION: AI/AN populations have a disproportionately high incidence of gastric cancer, especially in Alaska. High incidence in the central/distal portions of the stomach among AI/AN populations likely reflects a high prevalence of Helicobacter pylori infection in these populations. These data can be used to develop interventions to reduce risk factors and improve access to health services among AI/AN people at high risk for gastric cancer.

Effectiveness of Interventions to Increase Colorectal Cancer Screening Among American Indians and Alaska Natives.

INTRODUCTION: Screening rates for colorectal cancer are low in many American Indian and Alaska Native (AI/AN) communities. Direct mailing of a fecal immunochemical test (FIT) kit can address patient and structural barriers to screening. Our objective was to determine if such an evidence-based intervention could increase colorectal cancer screening among AI/AN populations. METHODS: We recruited study participants from 3 tribally operated health care facilities and randomly assigned them to 1 of 3 study groups: 1) usual care, 2) mailing of FIT kits, and 3) mailing of FIT kits plus follow-up outreach by telephone and/or home visit from an American Indian Community Health Representative (CHR). RESULTS: Among participants who received usual care, 6.4% returned completed FIT kits. Among participants who were mailed FIT kits without outreach, 16.9% returned the kits - a significant increase over usual care (P < .01). Among participants who received mailed FIT kits plus CHR outreach, 18.8% returned kits, which was also a significant increase over usual care (P < .01) but not a significant increase compared with the mailed FIT kit-only group (P = .44). Of 165 participants who returned FIT kits during the study, 39 (23.6%) had a positive result and were referred for colonoscopy of which 23 (59.0%) completed the colonoscopy. Twelve participants who completed a colonoscopy had polyps, and 1 was diagnosed with colorectal cancer. CONCLUSION: Direct mailing of FIT kits to eligible community members may be a useful, population-based strategy to increase colorectal cancer screening among AI/AN people.

Disparities in Cancer Incidence and Trends among American Indians and Alaska Natives in the United States, 2010-2015.

BACKGROUND: Cancer incidence rates for American Indian and Alaska Native (AI/AN) populations vary by geographic region in the United States. The purpose of this study is to examine cancer incidence rates and trends in the AI/AN population compared with the non-Hispanic white population in the United States for the years 2010 to 2015. METHODS: Cases diagnosed during 2010 to 2015 were identified from population-based cancer registries and linked with the Indian Health Service (IHS) patient registration databases to describe cancer incidence rates in non-Hispanic AI/AN persons compared with non-Hispanic whites (whites) living in IHS purchased/referred care delivery area counties. Age-adjusted rates were calculated for the 15 most common cancer sites, expressed per 100,000 per year. Incidence rates are presented overall as well as by region. Trends were estimated using joinpoint regression analyses. RESULTS: Lung and colorectal cancer incidence rates were nearly 20% to 2.5 times higher in AI/AN males and nearly 20% to nearly 3 times higher in AI/AN females compared with whites in the Northern Plains, Southern Plains, Pacific Coast, and Alaska. Cancers of the liver, kidney, and stomach were significantly higher in the AI/AN compared with the white population in all regions. We observed more significant decreases in cancer incidence rates in the white population compared with the AI/AN population. CONCLUSIONS: Findings demonstrate the importance of examining cancer disparities between AI/AN and white populations. Disparities have widened for lung, female breast, and liver cancers. IMPACT: These findings highlight opportunities for targeted public health interventions to reduce AI/AN cancer incidence.

Incidence of primary liver cancer in American Indians and Alaska Natives, US, 1999-2009.

PURPOSE: To evaluate liver cancer incidence rates and risk factor correlations in non-Hispanic AI/AN populations for the years 1999-2009. METHODS: We linked data from 51 central cancer registries with the Indian Health Service patient registration databases to improve identification of the AI/AN population. Analyses were restricted to non-Hispanic persons living in Contract Health Service Delivery Area counties. We compared age-adjusted liver cancer incidence rates (per 100,000) for AI/AN to white populations using rate ratios. Annual percent changes (APCs) and trends were estimated using joinpoint regression analyses. We evaluated correlations between regional liver cancer incidence rates and risk factors using Pearson correlation coefficients. RESULTS: AI/AN persons had higher liver cancer incidence rates than whites overall (11.5 versus 4.8, RR = 2.4, 95% CI 2.3-2.6). Rate ratios ranged from 1.6 (Southwest) to 3.4 (Northern Plains and Alaska). We observed an increasing trend among AI/AN persons (APC 1999-2009 = 5%). Rates of distant disease were higher in the AI/AN versus white population for all regions except Alaska. Alcohol use (r = 0.84) and obesity (r = 0.79) were correlated with liver cancer incidence by region. CONCLUSIONS: Findings highlight disparities in liver cancer incidence between AI/AN and white populations and emphasize opportunities to decrease liver cancer risk factor prevalence.

Evaluating a Modular Decision Support Application For Colorectal Cancer Screening.

BACKGROUND: There is a need for health information technology evaluation that goes beyond randomized controlled trials to include consideration of usability, cognition, feedback from representative users, and impact on efficiency, data quality, and clinical workflow. This article presents an evaluation illustrating one approach to this need using the Decision-Centered Design framework. OBJECTIVE: To evaluate, through a Decision-Centered Design framework, the ability of the Screening and Surveillance App to support primary care clinicians in tracking and managing colorectal cancer testing. METHODS: We leveraged two evaluation formats, online and in-person, to obtain feedback from a range primary care clinicians and obtain comparative data. Both the online and in-person evaluations used mock patient data to simulate challenging patient scenarios. Primary care clinicians responded to a series of colorectal cancer-related questions about each patient and made recommendations for screening. We collected data on performance, perceived workload, and usability. Key elements of Decision-Centered Design include evaluation in the context of realistic, challenging scenarios and measures designed to explore impact on cognitive performance. RESULTS: Comparison of means revealed increases in accuracy, efficiency, and usability and decreases in perceived mental effort and workload when using the Screening and Surveillance App. CONCLUSION: The results speak to the benefits of using the Decision-Centered Design approach in the analysis, design, and evaluation of Health Information Technology. Furthermore, the Screening and Surveillance App shows promise for filling decision support gaps in current electronic health records.

Influences and Practices in Colorectal Cancer Screening Among Health Care Providers Serving Northern Plains American Indians, 2011-2012.

INTRODUCTION: The epidemiology of colorectal cancer, including incidence, mortality, age of onset, stage of diagnosis, and screening, varies regionally among American Indians. The objective of the Improving Northern Plains American Indian Colorectal Cancer Screening study was to improve understanding of colorectal cancer screening among health care providers serving Northern Plains American Indians. METHODS: Data were collected, in person, from a sample of 145 health care providers at 27 health clinics across the Northern Plains from May 2011 through September 2012. Participants completed a 32-question, self-administered assessment designed to assess provider practices, screening perceptions, and knowledge. RESULTS: The proportion of providers who ordered or performed at least 1 colorectal cancer screening test for an asymptomatic, average-risk patient in the previous month was 95.9% (139 of 145). Of these 139 providers, 97.1% ordered colonoscopies, 12.9% ordered flexible sigmoidoscopies, 73.4% ordered 3-card, guaiac-based, fecal occult blood tests, and 21.6% ordered fecal immunochemical tests. Nearly two-thirds (64.7%) reported performing in-office guaiac-based fecal occult blood tests using digital rectal examination specimens. Providers who reported receiving a formal update on colorectal cancer screening during the previous 24 months were more likely to screen using digital rectal exam specimens than providers who had received a formal update on colorectal cancer screening more than 24 months prior (73.9% vs 56.9%, respectively, χ2 = 4.29, P = .04). CONCLUSION: Despite recommendations cautioning against the use of digital rectal examination specimens for colorectal cancer screening, the practice is common among providers serving Northern Plains American Indian populations. Accurate up-to-date, ongoing education for patients, the community, and health care providers is needed.

Designing Colorectal Cancer Screening Decision Support: A Cognitive Engineering Enterprise.

Adoption of clinical decision support has been limited. Important barriers include an emphasis on algorithmic approaches to decision support that do not align well with clinical work flow and human decision strategies, and the expense and challenge of developing, implementing, and refining decision support features in existing electronic health records (EHRs). We applied decision-centered design to create a modular software application to support physicians in managing and tracking colorectal cancer screening. Using decision-centered design facilitates a thorough understanding of cognitive support requirements from an end user perspective as a foundation for design. In this project, we used an iterative design process, including ethnographic observation and cognitive task analysis, to move from an initial design concept to a working modular software application called the Screening & Surveillance App. The beta version is tailored to work with the Veterans Health Administration's EHR Computerized Patient Record System (CPRS). Primary care providers using the beta version Screening & Surveillance App more accurately answered questions about patients and found relevant information more quickly compared to those using CPRS alone. Primary care providers also reported reduced mental effort and rated the Screening & Surveillance App positively for usability.

Causes and Disparities in Death Rates Among Urban American Indian and Alaska Native Populations, 1999-2009.

OBJECTIVES: To characterize the leading causes of death for the urban American Indian/Alaska Native (AI/AN) population and compare with urban White and rural AI/AN populations. METHODS: We linked Indian Health Service patient registration records with the National Death Index to reduce racial misclassification in death certificate data. We calculated age-adjusted urban AI/AN death rates for the period 1999-2009 and compared those with corresponding urban White and rural AI/AN death rates. RESULTS: The top-5 leading causes of death among urban AI/AN persons were heart disease, cancer, unintentional injury, diabetes, and chronic liver disease and cirrhosis. Compared with urban White persons, urban AI/AN persons experienced significantly higher death rates for all top-5 leading causes. The largest disparities were for diabetes and chronic liver disease and cirrhosis. In general, urban and rural AI/AN persons had the same leading causes of death, although urban AI/AN persons had lower death rates for most conditions. CONCLUSIONS: Urban AI/AN persons experience significant disparities in death rates compared with their White counterparts. Public health and clinical interventions should target urban AI/AN persons to address behaviors and conditions contributing to health disparities.

A Process Evaluation of the Alaska Native Colorectal Cancer Family Outreach Program.

This article presents the results of a process evaluation of the Alaska Native (AN) Colorectal Cancer (CRC) Family Outreach Program, which encourages CRC screening among AN first-degree relatives (i.e., parents, siblings, adult children; hereafter referred to as relatives) of CRC patients. Among AN people incidence and death rates from CRC are the highest of any ethnic/racial group in the United States. Relatives of CRC patients are at increased risk; however, CRC can be prevented and detected early through screening. The evaluation included key informant interviews (August to November 2012) with AN and non-AN stakeholders and program document review. Five key process evaluation components were identified: program formation, evolution, outreach responses, strengths, and barriers and challenges. Key themes included an incremental approach that led to a fully formed program and the need for dedicated, culturally competent patient navigation. Challenges included differing relatives' responses to screening outreach, health system data access and coordination, and the program impact of reliance on grant funding. This program evaluation indicated a need for more research into motivating patient screening behaviors, electronic medical records systems quality improvement projects, improved data-sharing protocols, and program sustainability planning to continue the dedicated efforts to promote screening in this increased risk population.

Use of Tracking and Reminder Systems for Colorectal Cancer Screening in Indian Health Service and Tribal Facilities.

BACKGROUND: Colorectal cancer (CRC) is a significant cause of morbidity and mortality among American Indian/Alaska Native (AI/AN) people. Screening at recommended intervals can detect CRC in its early, most treatable stages, or prevent CRC through removal of precancerous polyps. However, CRC screening percentages remain low among AI/AN people. Reminder and tracking systems can be used to improve CRC screening percentages. PURPOSE: In this study we assessed the prevalence of CRC screening reminder and tracking systems in Indian Health Service (IHS), Tribal, or Urban (I/T/U) health facilities. METHODS: A telephone survey of randomly selected small, medium and large I/T/U health facilities nationwide was conducted. Three health facilities from each of the 12 IHS areas nationwide were selected from a list of I/T/U healthcare facilities that provide CRC screening or refer patients to another facility for screening, with the goal of having one small, one medium, and one large I/T/U health facility from each IHS area. RESULTS: Thirty-four facilities (94%) participated in the telephone survey between April 1 and September 24, 2010. All facilities used the IHS Resource and Patient Management System to manage their patient care, and 82% used the Electronic Health Record (EHR) version. Over half of these facilities (55%) performed in-office fecal occult blood tests (FOBT) collected during a digital rectal exam, all of which reported that they also sent FOBT cards home with patients. Fifty-three percent of facilities used an opportunistic, visit-based approach to CRC screening. Nearly a third (32%) of facilities reported using a reminder system to notify patients that they were due for CRC screening. Almost two-thirds (65%) of facilities used a reminder system to notify health care providers that patients were due for CRC screening. While 73% of facilities used a system to track whether patients were due for CRC screening, only 61% used a system to track patient results for CRC screening, and 42% used a system to track patients with a personal history of polyps or CRC. CONCLUSIONS: A majority of facilities performed in-office FOBT tests using a digital rectal exam, which is a practice that is contrary to national CRC screening recommendations. Additionally, the majority of facilities reported not using an organized system for CRC screening. Use of patient reminders was suboptimal. However, facilities did report use of provider reminders, tracking when patients were due for CRC screening, and tracking CRC screening results. As the EHR system becomes more widely used and established, I/T/U facilities could be encouraged to increase their use of the EHR tools available to aid in systematically increasing CRC screening percentages.

Geographic variation in colorectal cancer incidence and mortality, age of onset, and stage at diagnosis among American Indian and Alaska Native people, 1990-2009.

OBJECTIVES: We characterized estimates of colorectal cancer (CRC) in American Indians/Alaska Natives (AI/ANs) compared with Whites using a linkage methodology to improve AI/AN classification in incidence and mortality data. METHODS: We linked incidence and mortality data to Indian Health Service enrollment records. Our analyses were restricted to Contract Health Services Delivery Area counties. We analyzed death and incidence rates of CRC for AI/AN persons and Whites by 6 regions from 1999 to 2009. Trends were described using linear modeling. RESULTS: The AI/AN colorectal cancer incidence was 21% higher and mortality 39% higher than in Whites. Although incidence and mortality significantly declined among Whites, AI/AN incidence did not change significantly, and mortality declined only in the Northern Plains. AI/AN persons had a higher incidence of CRC than Whites in all ages and were more often diagnosed with late stage CRC than Whites. CONCLUSIONS: Compared with Whites, AI/AN individuals in many regions had a higher burden of CRC and stable or increasing CRC mortality. An understanding of the factors driving these regional disparities could offer critical insights for prevention and control programs.

Comparison of fecal occult blood tests for colorectal cancer screening in an Alaska Native population with high prevalence of Helicobacter pylori infection, 2008-2012.

INTRODUCTION: Alaska Native colorectal cancer (CRC) incidence and mortality rates are the highest of any ethnic/racial group in the United States. CRC screening using guaiac-based fecal occult blood tests (gFOBT) are not recommended for Alaska Native people because of false-positive results associated with a high prevalence of Helicobacter pylori-associated hemorrhagic gastritis. This study evaluated whether the newer immunochemical FOBT (iFOBT) resulted in a lower false-positive rate and higher specificity for detecting advanced colorectal neoplasia than gFOBT in a population with elevated prevalence of H. pylori infection. METHODS: We used a population-based sample of 304 asymptomatic Alaska Native adults aged 40 years or older undergoing screening or surveillance colonoscopy (April 2008-January 2012). RESULTS: Specificity differed significantly (P < .001) between gFOBT (76%; 95% CI, 71%-81%) and iFOBT (92%; 95% CI, 89%-96%). Among H. pylori-positive participants (54%), specificity of iFOBT was even higher (93% vs 69%). Overall, sensitivity did not differ significantly (P = .73) between gFOBT (29%) and iFOBT (36%). Positive predictive value was 11% for gFOBT and 32% for iFOBT. CONCLUSION: The iFOBT had a significantly higher specificity than gFOBT, especially in participants with current H. pylori infection. The iFOBT represents a potential strategy for expanding CRC screening among Alaska Native and other populations with elevated prevalence of H. pylori, especially where access to screening endoscopy is limited.