Smoking Patterns Among Urban Alaska Native and American Indian Adults: The Alaska EARTH 10-Year Follow-up Study.

INTRODUCTION: Data on cigarette smoking prevalence among Alaska Native and American Indian (ANAI) people are limited to cross-sectional studies or specific subpopulations. Using data from the Alaska Education and Research toward Health (EARTH) Study 10-year follow-up, this study assessed patterns of smoking from baseline and factors associated with current use. AIMS AND METHODS: EARTH Study urban south central ANAI participants (N = 376; 73% women) provided questionnaire data on smoking at baseline and 10-year follow-up. Multivariable-adjusted logistic regression assessed whether gender, cultural factors (Tribal identity, language spoken in the home), depressive symptoms (PHQ-9), baseline smoking status, and baseline cigarettes per day (CPD) were associated with current smoking at follow-up. RESULTS: Current smoking was 27% and 23% at baseline and follow-up, respectively. Of baseline smokers, 60% reported smoking at follow-up (77% men, 52% women). From multivariable-adjusted analyses, the odds of current smoking at follow-up were lower among women than men, those who never or formerly smoked versus currently smoked at baseline, and smoking <10 CPD compared with ≥10 CPD at baseline. PHQ-9 score or cultural variables were not associated with smoking at follow-up. Smoking fewer baseline CPD was associated with former smoking status (ie, quitting) at follow-up among women, but not men. CONCLUSIONS: Our project is among the first to longitudinally explore smoking within an ANAI cohort. While we observed persistent smoking during a 10-year period, there were important differences by gender and CPD in quitting. These differences may be important to enhance the reach and efficacy of cessation interventions for ANAI people. IMPLICATIONS: This study contributes novel longitudinal information on cigarette smoking prevalence during a 10-year period among Alaska Native and American Indian (ANAI) people. Prior data on smoking prevalence among ANAI people are limited to cross-sectional studies or specific subpopulations. Our project is among the first to longitudinally explore smoking prevalence within an ANAI cohort. We observed persistent smoking during a 10-year period. The study also contributes information on differences by gender and cigarettes smoked per day in quitting. These findings have implications for enhancing the reach and efficacy of cessation interventions for ANAI people.

Follow-up Study Methods for a Longitudinal Cohort of Alaska Native and American Indian People Living within Urban South Central Alaska: The EARTH Study.

Longitudinal data are needed to investigate chronic disease causation and improve prevention efforts for Alaska Native and American Indian (ANAI) people. This paper describes the methods used to conduct follow-up data collection of a longitudinal cohort that enrolled ANAI adults between 2004 and 2006 in south central Alaska. The follow-up study re-examined ANAI participants in a large, urban centre in south central Alaska between 2015 and 2017. Computerized surveys were used to collect self-reported health, lifestyle, physical activity, and diet data. Clinical measurements included blood pressure, fasting blood glucose and lipid panel, urine albumin/creatinine, height, weight, and waist and hip circumference. Participants were provided individual results at the conclusion of their visit. A total of 1320 south central Alaska study participants completed the baseline visit. Study staff attempted to contact all living cohort members for inclusion in the follow-up study. More than 11,000 attempted contacts were made. Of the 637 available for participation, 388 completed the follow-up visit. The proportion of women increased from baseline to follow-up examinations (67 vs. 72%, p < 0.01). Self-reported health status of being married or living as married (46% vs. 39%, p < 0.01), and those reporting being employed or self-employed (55% vs. 47%, p < 0.01) were higher at follow-up when compared to baseline. Almost all participants at follow-up (97%) agreed to long-term storage of biological specimens for future study. Despite demographic differences between the follow-up and baseline cohorts, longitudinal data collected will provide novel insight on chronic disease development and prevention for ANAI people as well as other populations.

Elevated Adenomatous Polyp Detection Rate Among Alaska Native and American Indian People in Interior Alaska, 2018-2022.

OBJECTIVES: Colorectal cancer (CRC) incidence and mortality are twice as high among Alaska Native people as among non-Hispanic White people in the United States; as such, colonoscopy is a recommended screening test for Alaska Native people. Adenoma detection rate (ADR) is measured in patients at average risk of CRC undergoing initial screening colonoscopy and reflects the prevalence of precancerous polyps in a screened population. We evaluated the ADR among Alaska Native people living in Interior Alaska. METHODS: This project evaluated the ADR among Alaska Native and American Indian adults aged ≥40 years (N = 460) living in Interior Alaska, using a retrospective medical record review of patients referred for screening colonoscopy from February 1, 2018, through March 31, 2022. The main outcome measure was ADR, stratified by age and sex. RESULTS: The ADR was 45.0% overall: 43.0% among women and 47.1% among men. Among patients aged ≥50 years, the ADR was 67.1%: 62.7% among women and 70.7% among men. Among patients aged 40-49 years, the ADR was 34.4%: 35.3% among women and 33.3% among men. CONCLUSIONS: Measured ADR was high among Alaska Native men and women aged ≥50 years in Interior Alaska and in all age groups that were screened. These findings have implications for which CRC screening methods, intervals, and age to begin screening are most appropriate for Alaska Native people, as well as the need for future research on the pathology, etiology, and natural history of CRC in this population.

Cancer Screening Prevalence among Participants in the Southcentral Alaska Education and Research towards Health (EARTH) Study at Baseline and Follow-Up.

Alaska Native communities are working to prevent cancer through increased cancer screening and early detection. We examined the prevalence of self-reported colorectal (CRC), cervical, and breast cancer screening among Alaska Native participants in the southcentral Alaska Education and Research toward Health (EARTH) study at baseline (2004-2006) and ten-year follow-up (2015-2017); participant characteristics associated with screening; and changes in screening prevalence over time. A total of 385 participants completed questionnaires at follow-up; 72% were women. Of those eligible for CRC screening, 53% of follow-up participants reported a CRC screening test within the past 5 years, significantly less than at baseline (70%) (p = 0.02). There was also a significant decline in cervical cancer screening between baseline and follow-up: 73% of women at follow-up vs. 90% at baseline reported screening within the past three years (p < 0.01). There was no significant difference in reported breast cancer screening between baseline (78%) and follow-up (77%). Colorectal and cervical cancer screening prevalence in an urban, southcentral Alaska Native cohort declined over 10 years of follow-up. Increased cancer screening and prevention are needed to decrease Alaska Native cancer-related morbidity and mortality.

The Alaska Education and Research Towards Health (EARTH) Study: cancer risk factors.

The Alaska Education and Research Towards Health (EARTH) Study assessed cancer risk among 3,821 Alaska Native people (AN). We present the prevalence of selected cancer risk factors and comparison with Healthy People 2010 goals. Participants completed extensive computer-assisted self-administered questionnaires on diet, physical activity, tobacco and alcohol use, cancer screening, family history of cancer, and environmental exposures. Measurement data were collected on blood pressure, height, weight, waist/hip circumference, fasting serum lipids, and glucose. Cancer risk factors are high for the Alaska EARTH study population. For all risk factors studied except for vegetable consumption, Alaska EARTH Study participants did not meet Healthy People 2010 goals. This study is unique in providing questionnaire and measurement data of cancer risk factors on a larger study sample than any previous study among AN living in Alaska. Data show that the prevalence of most cancer risk factors exceeded national recommendations. Given the disease disparities that exist for the AN population, these data provide important baseline data that can be used to target health interventions and reduce health disparities.

Development of a colorectal cancer screening intervention for Alaska Native people during a pandemic year.

Objectives: Alaska Native (AN) people experience twice the rate of colorectal cancer (CRC) as US Whites. There is a need for increased screening and early detection. We describe the development and implementation of a randomized controlled trial of the multi-target stool DNA test (mt-sDNA; Cologuard® Exact Sciences, Madison WI) to increase CRC screening among AN people. Methods: A total of 32 rural/remote AN communities were randomized to a varied intensity intervention (patient navigation vs mailed health education) compared to 14 communities receiving usual opportunistic care. Outcome measures include screening completion and method used (mt-sDNA vs colonoscopy). Health care provider interviews and AN patient focus groups will be used to assess patient-, provider-, and system-level CRC screening promoters and barriers. Results: The study began in April 2020 during the COVID-19 pandemic, resulting in a number of challenges and study adaptations. These included difficulty finding laboratory space, lack of timely mail service due to flight reductions across the state, and travel restrictions that led to postponement of in-person focus groups. Videoconferencing platforms for Tribal engagement replaced face-to-face interactions. After an extensive search, a laboratory with space available was identified and the preprocessing laboratory established. Study staff will work closely with patients to monitor mail service to get mt-sDNA kits sent on time. We are also exploring the use of videoconferencing platforms as alternatives to in-person focus groups. Conclusions: Despite the challenges encountered during the COVID-19 pandemic, we successfully initiated the intervention and established the first mt-sDNA preprocessing laboratory in Alaska.

Cost-Effectiveness of Multitarget Stool DNA Testing vs Colonoscopy or Fecal Immunochemical Testing for Colorectal Cancer Screening in Alaska Native People.

OBJECTIVE: To estimate the cost-effectiveness of multitarget stool DNA testing (MT-sDNA) compared with colonoscopy and fecal immunochemical testing (FIT) for Alaska Native adults. PATIENTS AND METHODS: A Markov model was used to evaluate the 3 screening test effects over 40 years. Outcomes included colorectal cancer (CRC) incidence and mortality, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). The study incorporated updated evidence on screening test performance and adherence and was conducted from December 15, 2016, through November 6, 2019. RESULTS: With perfect adherence, CRC incidence was reduced by 52% (95% CI, 46% to 56%) using colonoscopy, 61% (95% CI, 57% to 64%) using annual FIT, and 66% (95% CI, 63% to 68%) using MT-sDNA. Compared with no screening, perfect adherence screening extends life by 0.15, 0.17, and 0.19 QALYs per person with colonoscopy, FIT, and MT-sDNA, respectively. Colonoscopy is the most expensive strategy: approximately $110 million more than MT-sDNA and $127 million more than FIT. With imperfect adherence (best case), MT-sDNA resulted in 0.12 QALYs per person vs 0.05 and 0.06 QALYs per person by FIT and colonoscopy, respectively. Probabilistic sensitivity analyses supported the base-case analysis. Under varied adherence scenarios, MT-sDNA either dominates or is cost-effective (ICERs, $1740-$75,868 per QALY saved) compared with FIT and colonoscopy. CONCLUSION: Each strategy reduced costs and increased QALYs compared with no screening. Screening by MT-sDNA results in the largest QALY savings. In Markov model analysis, screening by MT-sDNA in the Alaska Native population was cost-effective compared with screening by colonoscopy and FIT for a wide range of adherence scenarios.

Chronic disease risk factors among Alaska Native and American Indian people, Alaska, 2004-2006.

INTRODUCTION: The Alaska Education and Research Towards Health (EARTH) Study is being conducted to determine the prevalence of clinically measured chronic disease risk factors in a large population of American Indian/Alaska Native people (AI/AN). We report these estimates and compare them with those for the overall US population, as assessed by the National Health and Nutrition Examination Survey (NHANES). METHODS: We measured blood pressure, height, weight, and fasting serum lipids and glucose in a prospective cohort of 3,822 AI/AN participants who resided in Alaska during 2004 through 2006. We categorized participants as having chronic disease risk factors if their measurements exceeded cutoffs that were determined on the basis of national recommendations. We analyzed the prevalence of risk factors by sex and age and compared the age-adjusted prevalence with 1999-2004 NHANES measurements. RESULTS: EARTH participants were significantly more likely than NHANES participants to be overweight or obese and to have impaired fasting glucose, low high-density lipoprotein cholesterol, high low-density lipoprotein cholesterol, and hypertension. The prevalence of high total cholesterol and triglycerides was not significantly different between the 2 study populations. CONCLUSION: We provide baseline clinical measurements for chronic disease risk factors for a larger study sample than any previous study of AI/AN living in Alaska. The prevalence of most risk factors measured exceeded national rates. These data can be used to tailor health interventions and reduce health disparities.

Increase in diabetes among urban Alaska Native people in the Alaska EARTH follow-up study: A call for prediabetes screening, diagnosis, and referral for intervention.

AIMS: This study estimates incidence of diabetes (DM) and pre-DM relative to DM risk factors among relatively healthy Alaska Native and American Indian (henceforth AN) adults living in urban south central Alaska. METHODS: Baseline (2004-2006) and follow-up (2014-2017) surveys, blood samples, and medical chart review data were collected from AN adults living in south central Alaska. We analyzed associations between prevalent risk factors and incident DM and pre-DM using Cox proportional hazards and used multivariable models to identify independent predictors for both DM and pre-DM. RESULTS: Among 379 participants with follow-up data, overall DM incidence was 16.5/1,000 PY; overall pre-DM incidence was 77.6/1,000 PY, with marked differences between men and women. Prevalent cardiometabolic risk factors also varied with greater amounts of overweight in men and greater amounts of obesity in women. Controlling for age and sex, obesity, abdominal adiposity, pre-DM, and metabolic syndrome independently increased DM risk. CONCLUSION: Health care providers of AN populations must seize the opportunity to screen, refer, and treat individuals with pre-DM and other modifiable DM risk factors prior to DM diagnosis if we are to alter the epidemiologic course of disease progression in this urban AN population.

Alaska Native Patient and Provider Perspectives on the Multitarget Stool DNA Test Compared With Colonoscopy for Colorectal Cancer Screening.

Objective: Alaska Native (AN) people have among the world's highest rate of colorectal cancer (CRC). We assessed perceptions of AN people and their health care providers of a new take-home multitarget stool DNA test (MT-sDNA; Cologuard) relative to colonoscopy. Methods: Cross-sectional surveys of AN people aged 40 to 75 years (mailed) and providers (online). Results: Participants included 1616 AN patients (19% response rate) and 87 providers (26% response rate; 57% AN people). Over half (58%) of patients preferred colonoscopy for CRC screening, while 36% preferred MT-sDNA. Unscreened patients were significantly more likely to state a preference for MT-sDNA than previously screened patients (42% vs 31%, P < .05) as were younger patients (<60 years old) compared with older patients (40% vs 30%, P < .05). Most providers thought that MT-sDNA would improve screening rates (69%), would recommend if available (79%), and be implementable (79%). Perceived barriers differed substantially between patients and providers in both type and magnitude. Leading colonoscopy barriers reported by patients were travel (44%) and bowel preparation (40%), while providers thought that fear of pain (92%) and invasiveness of the test (87%) were the primary barriers. For MT-sDNA, patients' belief that colonoscopy was better (56%) and not knowing how to do the test (40%) were primary barriers, while providers thought stool collection (67%) and having a stool sample in their home (63%) were leading barriers. Conclusions: This study found that MT-sDNA has potential acceptability among AN people and their health care providers. Both groups reported a willingness to use MT-sDNA and did not perceive major barriers to its use. This preference was especially true of unscreened and younger patients. The majority of providers indicated they would use MT-sDNA if available and that it would improve CRC screening rates. In this population, where colonoscopy access is limited, MT-sDNA has the potential to improve CRC screening adherence.

Alaska Native Traditional Food and Harvesting Activity Patterns over 10 Years of Follow-Up.

BACKGROUND: Alaska Native (AN) traditional foods and associated harvesting activities are beneficial to human health. OBJECTIVE: This study assessed longitudinal self-reported traditional food use and harvesting activities among Alaska Native and American Indian (AN/AI) participants in the Alaska Education and Research Towards Health (EARTH) study. METHODS: In 2004-2006, southcentral Alaska EARTH study participants (n = 1320) completed diet and activity questionnaires which were repeated in 2015-2017; results were compared between participants who completed both questionnaires (n = 388). RESULTS: In the follow-up questionnaire, >93% of participants reported eating ≥1 traditional food in the past year. The top 3 traditional foods were fish (75%), moose (42%), and shellfish (41%). Women were more likely than men to consume traditional foods, especially fish, gathered berries, shellfish, and seal oil (P < 0.05). Participants aged ≥60 y in the original cohort were significantly more likely to consume fish and shellfish at follow-up, whereas those aged 40-59 y were the most likely of the 3 age groups to consume seal oil (P < 0.05). Between the original cohort and follow-up, there was a significant decline in the mean number of traditional foods eaten from 6.3 to 5.5, as well as reduced consumption of multiple traditional foods (P < 0.001). Over 59% of participants reported ≥1 traditional harvesting activity in the past year; this proportion did not significantly change between baseline and follow-up. Picking berries/greens (44%), cutting/smoking fish or meat (33%), and fishing (30%) were the most common activities. Participation in traditional harvesting activities was greater among women than men (P < 0.05), but did not differ by age. CONCLUSIONS: Longitudinal follow-up demonstrated that AN/AI people maintained participation in traditional harvesting activities, but the variety of traditional foods declined significantly among both men and women. Promotion of traditional foods and harvesting activities that serve as protective factors against chronic diseases may benefit this population.

Traditional foods and physical activity patterns and associations with cultural factors in a diverse Alaska Native population.

OBJECTIVES: To determine the prevalence of traditional food and physical activity use and associations with cultural factors among 3,830 Alaska Native and American Indian (AN/AI) people enrolled in the Education and Research Towards Health (EARTH) Study in 3 regions of Alaska. STUDY DESIGN: Cross-sectional analysis of baseline data from a cohort study. METHODS: Participants (2,323 women and 1,507 men) completed a computer-assisted self-administered questionnaire that included information on diet, physical activity, life-style and cultural factors. RESULTS: Over 92% of participants reported eating at least 1 traditional food in the past year. The top 3 traditional foods reported were fish, moose and agutaq (a mixture of berries and fat). The percentage of people who consumed traditional foods varied by region and age but not by sex (p < 0.01). Almost 70% of participants engaged in at least one traditional harvesting physical activity. Picking berries or greens, cutting/smoking fish or meat and fishing were the most common activities. Participation in traditional physical activity was highest in south-west Alaska and was higher among men than women, but did not differ by age (p < 0.01). Both traditional food and physical activity were associated with greater tribal self-identification, speaking a Native language at home, using traditional remedies and participating in or attending traditional events (p < 0.05). CONCLUSIONS: The EARTH Study found relationships between traditional food use, physical activities, cultural activities and behaviours. Consumption of a variety of traditional foods and participation in traditional physical activities remain an important part of the contemporary Alaska Native life-style. Efforts to promote and sustain these foods and activities in AN/AI populations may lead to improved health outcomes.

Stool DNA Testing for Screening Detection of Colorectal Neoplasia in Alaska Native People.

OBJECTIVE: To assess the accuracy of a multitarget stool DNA test (MT-sDNA) compared with fecal immunochemical testing for hemoglobin (FIT) for detection of screening-relevant colorectal neoplasia (SRN) in Alaska Native people, who have among the world's highest rates of colorectal cancer (CRC) and limited access to conventional screening approaches. PATIENTS AND METHODS: We performed a prospective, cross-sectional study of asymptomatic Alaska Native adults aged 40-85 years and older undergoing screening or surveillance colonoscopy between February 6, 2012, and August 7, 2014. RESULTS: Among 868 enrolled participants, 661 completed the study (403 [61%] women). Overall, SRN detection by MT-sDNA (49%) was superior to that by FIT (28%; P<.001); in the screening group, SRN detection rates were 50% and 31%, respectively (P=.01). Multitarget stool DNA testing detected 62% of adenomas 2 cm or larger vs 29% by FIT (P=.05). Sensitivity by MT-sDNA increased with adenoma size (to 80% for lesions ≥3 cm; P=.01 for trend) and substantially exceeded FIT sensitivity at all adenoma sizes. For sessile serrated polyps larger than 1 cm (n=9), detection was 67% by MT-sDNA vs 11% by FIT (P=.07). For CRC (n=10), detection was 100% by MT-sDNA vs 80% by FIT (P=.48). Specificities were 93% and 96%, respectively (P=.03). CONCLUSION: The sensitivity of MT-sDNA for cancer and larger polyps was high and significantly greater than that of FIT for polyps of any size, while specificity was slightly higher with FIT. These findings could translate into high cumulative neoplasm detection rates on serial testing within a screening program. The MT-sDNA represents a potential strategy to expand CRC screening and reduce CRC incidence and mortality, especially where access to endoscopy is limited.

Reproductive cancer risk factors among Alaska Native women: the Alaska Education and Research Towards Health (EARTH) Study.

BACKGROUND: The purpose of this study was to provide estimates for the prevalence of reproductive cancer risk factors among Alaska Native (AN) women who enrolled in the Alaska Education and Research Towards Health (EARTH) Study from 2004 to 2006. METHODS: A total of 2,315 AN women 18 years or older completed reproductive health questions as part of a comprehensive health history questionnaire. The reproductive health section included menstrual status (age at menarche and menopause), pregnancy and live birth history, use of hormonal contraception, hormone replacement therapy, and history of hysterectomy and/or oophorectomy. RESULTS: A total of 463 (20%) of women experienced menarche before age 12 with a decline in mean age at menarche by age cohort. More than 86% had been pregnant (mean number of pregnancies, 3.8; mean number of live births, 2.9). More than one half of women (58%) had their first live birth between the ages of 18 and 24. Almost 28% of participants had completed menopause, of whom 24% completed menopause after age 52. Fewer than half (43%) reported ever using hormone replacement therapy. Almost two thirds (62%) reported ever using oral contraceptives, and fewer reported ever using birth control shots (30%) or implants (10%). CONCLUSIONS: This study is unique in reporting reproductive health factors among a large group of AN women. These data show that AN women have selective protective factors for reproductive cancers, including low nulliparity rates, low use of menopausal estrogens, and common use of contraceptive hormones. However, analysis by age cohorts indicates decreasing age at menarche that might increase the risk for reproductive cancers among AN women in the future.

Construct validity of the SF-12 among American Indian and Alaska Native people using two known scoring methods.

OBJECTIVE: This study evaluated the construct validity of the 12-Item Short Form Survey Instrument (SF-12) in a cohort of American Indian and Alaska Native (AIAN) people. We evaluated two scoring methods to determine their utility in this population. METHODS: Participants (N = 11,127) were aged 18 and older, self-identified as AIAN, and had complete SF-12 interview data. Physical and mental health summary scores were calculated using traditional SF-12 (PCS12 and MCS12) and RAND-12 (PHC and MHC) scoring methods. RESULTS: Women scored lower than men on the PHC, PCS12, MHC, and MCS12, as did those with more medical conditions versus none. Those aged 55 and older scored lower on the PHC and PCS12 than younger people. There was no difference in the mean MCS12 score by age and for those 31-55 and aged older than 55 for the MHC. CONCLUSIONS: This study demonstrates the construct validity of the PCS12/MCS12 and PHC/MHC in a cohort of AIAN people.