Pilot Investigator: Wenjun Fan, PhD
The aim of this proposed study is to evaluate the effectiveness of two novel therapies, SGLT-2 inhibitors (SGLT-2is) and GLP-1 receptor agonists (GLP-1 RAs), on aging-related outcomes, specifically the risk of cardiovascular disease and dementia in American Indian and Alaska Native (AI/AN) adults with diabetes. Clinical trials have demonstrated these therapies could cause a 14%-26% risk reduction in cardiovascular events beyond the current standard of care, while recent meta-analyses and epidemiological studies have suggested an 11%-18% reduced risk of dementia associated with these therapies. However, the AI/AN population has been significantly underrepresented in these studies, leaving their efficacies in this group uncertain. To address this gap, we propose to utilize Medicare data to identify AI/AN adults with diabetes from 2015-2016, with follow-up data extending to 2024. We will compare the effectiveness of SGLT-2is, GLP-1 RAs, and traditional diabetes medications on the outcomes of incident or recurrent cardiovascular events and all-cause dementia. We anticipate identifying ~45,000 and ~ 28,000 AI/AN users of traditional and novel diabetes medications, respectively, in 2016, with higher expected sample sizes when including data from 2015. Propensity score matching will be employed to balance differences in patient characteristics between comparison groups, and Cox proportional hazards models will be used to estimate hazard ratios for each outcome. Our findings will provide robust evidence to support increased access to novel therapies within the AI/AN population, thereby improving diabetes care, life expectancy, and quality of life in this severely underserved population.
Project supported in part by American Diabetes Association.
Pilot Investigator: Marie Kainoa Fialkowski Revilla (Native Hawaiian), PhD, RDN, LD, IBC, CLC
Breastfeeding is a potent protective factor for many adverse perinatal outcomes and subsequent chronic conditions. Compared to non-breastfeeding counterparts, mothers who breastfed experience a 30% reduction in the risk of diabetes later in life while breastfeeding more than 13 months reduces diabetes risk by 32% in comparison to breastfeeding <1 month. Native Hawaiians (NH) have a higher incidence for type 2 diabetes in comparison to non-Hispanic whites and NH women in Hawai‘i are at high risk of gestational diabetes. The 2021 Hawaiʻi Pregnancy Risk Assessment Monitoring Surveys revealed that NH women are less likely to initiate breastfeeding and to be breastfeeding at 8 weeks. Most research on breastfeeding among NH women has been hampered by the problematic aggregation of Asian and NHPI women in national data emphasizing the need for disaggregated data sources. This study involves an analysis of the Multiethnic Cohort (MEC) Study to explore type 2 diabetes and breastfeeding history among NH women compared to the other MEC racial and ethnic groups. Breastfeeding history, duration, and related determinants, and how they differ for NH women compared to the other racial and ethnic groups, will be assessed. Then the association between the incidence of type 2 diabetes with breastfeeding duration and frequency among the NH women in comparison to the other MEC race and ethnic groups will be examined using Cox regression. Findings will inform future proposals seeking to address the relationship between type 2 diabetes and other chronic conditions with breastfeeding among NH women.
Pilot Investigator: Tara L. Maudrie (Sault Ste Marie Tribe of Chippewa Indians), PhD
The traditional foods and food practices of American Indian (AI) peoples have supported their health and the wellbeing of their environments since time immemorial. However, the intrusion of settler colonialism disrupted these relational food practices while introducing chronic diseases and food insecurity. In recent years, Indigenous food sovereignty initiatives have garnered attention for their efforts in promoting healthy food access and reinforcing connections to cultural foods. Cultural food security and connectedness to traditional foods are two potentially important indicators of traditional food intake and food sovereignty, but the effects of food sovereignty interventions on these indicators are not well studied.
A food sovereignty initiative led and implemented by the Osage Nation provided produce boxes delivered to community members through the Indigenous Supported Agriculture (ISA) study. The ISA study included approximately N = 353 AI participants aged 18-75 years, who were residents of Osage Nation, and classified as overweight and obese according to BMI criteria. This project’s secondary analysis of the ISA randomized control trial study will address the following aims: 1) Determine the associations between cultural food security, traditional food intake, cultural connectedness to traditional foods, and a primary outcome: physical activity. 2) Determine intervention effect on cultural food security, traditional food intake, cultural connectedness to food, and physical activity. This research will provide critical insights into the role of food sovereignty initiatives in promoting holistic health and cultural connectedness among Indigenous communities, while informing the design of future interventions to enhance these outcomes.
Pilot Investigator: Emily M. Melnick, PhD, MPH
Diets rich in fruits and vegetables promote overall health and reduce risk for diabetes. However, less than 40% of American Indian (AI) youth and adults meet fruit and vegetable intake recommendations. This gap is largely driven by systemic inequities in the food system that create barriers to accessing healthy foods. The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) provides a monthly cash value benefit (CVB) for purchasing fruits and vegetables, which could help improve intake among AI families. Yet, CVB redemption rates are relatively lower among WIC-participating AIs. The Inter Tribal Council of Arizona (ITCA) WIC—a state agency serving AI populations in Arizona, most of whom live on tribal lands—recently implemented two new policies to increase CVB purchasing flexibilities. The first allows households to use their CVBs to purchase canned produce in addition to fresh and frozen options. The second allows households with an infant to receive CVBs as a substitute for jarred infant fruit and vegetables. Our study partners at ITCA WIC want to learn about the uptake of these options and implications for redemption. Using administrative data from ITCA WIC, our team will (1) assess whether household characteristics, including WIC beneficiary composition, SNAP participation, and urbanicity, associate with uptake of new policies and (2) evaluate whether household CVB redemption rates vary by household patterns of utilizing expanded redemption options. Findings will inform future collaborative work with ITCA WIC to improve fruit and vegetable benefit redemption to maximize health benefits for participating AI families.
Reagan L. Miller, PhD, Assistant Professor, Colorado State University
Pilot Investigator: Reagan L. Miller, PhD
American Indian/Alaska Native (AI/AN) adolescents experience significant disparities in obesity and type 2 diabetes, due to social determinants of health including historical and ongoing experiences of adversity. Mental health problems (e.g., depression/suicidality) that can arise from adversity have also been related to greater risk of developing obesity/diabetes. Yet, most existing research has focused on AI/AN adults and utilized small sample sizes and it is unclear how mental health and adversity may contribute to obesity/diabetes risk among AI/AN adolescents. In addition, it is likely that holding more minoritized identities (e.g., identifying as AI/AN, lesbian/gay/bisexual) may increase the strength of the association between mental health concerns and obesity/diabetes risk, but this has yet to be explored. In an effort to clarify these relationships and inform the tailoring of culturally aware preventative intervention programs for AI/AN adolescents, we will leverage the CDC’s 2023 Youth Risk Behavior Surveillance System to: 1) evaluate the associations of mental health problems and two key dimensions of adversity (i.e., threat/deprivation) with body mass index (BMI) among AI/AN adolescents (Aim 1) and 2) assess the extent to adversity (threat/deprivation) and intersectional identities moderate the mental health-BMI connection (Aims 2/3). Findings from this study will serve as preliminary data for future NIH funding related to optimizing evidence-based preventative intervention programs to most effectively reduce disparities in obesity and type 2 diabetes risk among AI/AN adolescents.
Project supported in part by American Diabetes Association.
Melinda S. Smith, PhD, Postdoctoral Scholar, Northern Arizona University, Center for Health Equity Research
Pilot Investigator: Melinda S. Smith, PhD
Epidemiological evidence has shown that type 2 diabetes (T2D) increases risk for several cancers, including endometrial, colorectal, and breast cancer. Given that American Indian and Alaska Natives (AIAN) continue to suffer from disproportionately high rates of T2D and poor cancer survival outcomes, understanding the relationship between T2D and cancer among AIAN is critical to reduce secondary complications of T2D and cancer risk.Pilot Investigator: Kaipeng Wang, PhD
Pilot Investigator: Ginny Lane, PhD
Pilot Investigator: Maja Pederson, PhD