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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.

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 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.

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.

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.

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.

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.

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.

BACKGROUND. Colorectal cancer (CRC) is a leading cause of cancer morbidity and mortality for American Indians and Alaska Natives (AI/ANs), but misclassification of race causes underestimates of disease burden. METHODS. The authors compared regional differences in CRC incidence, stage at diagnosis, and anatomic distribution between AI/ANs and non-Hispanic whites (NHWs). To reduce misclassification, data from the National Program of Cancer Registries; the Surveillance, Epidemiology, and End Results Program; and the Indian Health Service (IHS) were linked. The analysis was limited to the 56% of AI/AN who live in IHS Contract Health Service Delivery Areas. RESULTS. From 1999 to 2004, the overall incidence rate (per 100,000 persons per year) of CRC was 9% lower in the AI/AN population (46.3) than in the NHW population (50.8). However, AI/AN CRC incidence rates varied nearly 5-fold regionally, from 21 in the Southwest to 102.6 in Alaska. Compared with NHW rates, AI/AN rates were significantly higher in Alaska (rate ratio [RR], 2.03), the Northern Plains (RR, 1.39), and the Southern Plains (RR, 1.16) but were lower in the Pacific Coast (RR, 0.80), the East (RR, 0.65), and the Southwest (RR, 0.45). AI/ANs were diagnosed more often with advanced CRC than with localized CRC (RR, 1.92) compared with NHWs (RR, 1.48). Females more often had proximal CRC among both the AI/AN population (females, 40.1%; males, 33.5%) and the NHW population (females, 50.1%; males, 40.3%), although AI/ANs had a higher proportion of distal cancers overall. CONCLUSIONS. CRC incidence rates in AI/AN populations varied dramatically between regions. Efforts are needed to make CRC screening a priority, overcome barriers to endoscopic screening, and to engage AI/AN communities in culturally appropriate ways to participate in prevention and early detection programs. Cancer 2008;113(5 suppl):1179–90. Published 2008 by the American Cancer Society.

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.

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.

Background. Provider recommendation is critical for colorectal cancer (CRC) screening participation, yet few data exist on practices of providers serving American Indians and Alaska Natives. We examined Indian Health Service (IHS) and tribal provider prac- tices, beliefs about screening efficacy, and perceptions of barriers. Methods. We developed a Web-based questionnaire and recruited respondents via electronic distribution lists. We generated descriptive statistics by region, provider type, and workplace setting. r esults. Most respondents (77%) recommend starting CRC screening of average-risk patients at age 50; however, 22% recommend flexible sigmoidoscopy and 43% colonoscopy at inter - vals inconsistent with national guidelines. Of those recommending fecal occult blood test (FOBT), 23% use a single, in-office FOBT card as their only FOBT method. Respondents reported barriers to screening to include underutilized reminder systems and inadequate resources. Conclusions. Indian Health Service/tribal providers are knowledgeable about when to begin CRC screening; however, education about the appropriate use and frequency of CRC tests is needed.