In a first-of-its-kind study, researchers from the University of California, Irvine, led a study that estimated the prevalence of Type 1 and Type 2 diabetes among American Indian and Alaska Native (AI/AN) of all ages and found that the AI/AN population has a notably higher prevalence of Type 2 diabetes compared to the general U.S. population across all ages starting at 10 years of age.
Corresponding author, Luohua Jiang, MD, PhD, interim chair and associate professor of epidemiology and biostatistics with the UCI Program in Public Health, collaborated with UCI doctoral student, Jiahui Dai, and colleagues at Centers for American Indian and Alaska Native Health, Colorado School of Public Health, to publish the study findings in the journal Diabetes Care.
These findings highlight the necessity of enhancing existing diabetes prevention interventions to curb the diabetes epidemic among the AI/AN community and many other underserved communities.”
For decades, limited data have been available when researching health and healthcare access in the AI/AN population due to historical, cultural, ethical and legal reasons. One notable example in 1989 is the unethical use of blood samples from members of the Havasupai Tribe. The participants consented to provide their blood to determine genetic links to diabetes among their tribe, instead, other researchers used their data to publish papers on inbreeding, alcoholism, and more. This violation of informed consent and many other examples cause distrust and high-level scrutiny when researchers try to access health-related data for AI/AN people.
Given this mistrust and misuse of health data, little is known about the prevalence of diabetes in the AI/AN community who face a greater risk of contracting diabetes compared to any other U.S. racial group. In collaboration with the Indian Health Service (IHS) and tribal health programs, Jiang and team were able to extract data from the IHS Improving Health Care Delivery Data Project, which represents nearly 30% of AI/AN individuals who use IHS services. From 2012-2013, a total of 55,049 AI/AN individuals were identified as having Type 1 diabetes or Type 2 diabetes and were comparatively analyzed with demographic markers like age, gender and geographic region.
Of the three main subtypes of diabetes, the team focused on data for Type 1 and Type 2 diabetes. Type 1 diabetes is thought to be caused by an autoimmune reaction where our body stops making insulin and requires lifetime treatment of insulin shots. It is usually the most common type of diabetes among children. Type 2 diabetes is when our body doesn’t process insulin sufficiently and can’t keep blood sugar at normal levels, which can be exacerbated by diet and lifestyle behavior. In the past, Type 2 diabetes was rarely found in children but its prevalence among children and youth has been rising in recent years.
The study findings observed that Type 1 diabetes was 1.5 times more prevalent among AI/AN children under 10 years old compared to Type 2 diabetes, but starting from age 10, the prevalence of Type 2 diabetes surpassed that of Type 1 diabetes. Experts suggest that a variety of factors are to blame for the surge in diabetes, including socioeconomic status, behavioral influences, environmental conditions, nutrition, and access to health care. There were also large regional variations between Type 1 and Type 2 diabetes prevalence where the Southern Plains (Kansas, Oklahoma, and Texas) had the highest Type 1 prevalence and the Eastern region (Mississippi, South Carolina, New York, and more) had the highest Type 2 diabetes prevalence.
“The higher prevalence of Type 2 diabetes in AI/AN youths is concerning given the implications for future prevalence and complications rates. These findings highlight the necessity of enhancing existing diabetes prevention interventions to curb the diabetes epidemic among the AI/AN community and many other underserved communities,” says Jiang. “Our data, albeit limited, to relatively older data still stresses the need to address both population level environmental conditions and individual risk factors unique to the AI/AN community.”
Additional authors on this study include Xiaoyi Niu, a previous MS student of Epidemiology & Biostatistics with the UC Irvine Program in Public Health, Ann Bullock with the Indian Health Service, and Spero Manson and Joan O’Connell with the Colorado School of Public Health. This study was supported by the National Institute on Aging (R01AG061189), National Institute of Diabetes and Digestive and Kidney Disease (P30DK092923), and the National Institute on Minority Health and Health Disparities (U54MD000507).
