The use of tobacco in American Indian and Alaskan Native (AI/AN) communities was first documented in the 1500 s, when Europeans colonized and commercialized traditional tobacco applications. This exploitative process continued when the ceremonial use of traditional tobacco was banned in the U.S and reliance on commercially available products was necessary [1]. The Cheyenne River Sioux Tribe (CRST), located in South Dakota, is one of many Indigenous communities that has been targeted by the tobacco industry, resulting in increased exposure to nicotine [2, 3]. Indigenous communities across the U.S have a disproportionately high commercial tobacco use (cigarettes, electronic cigarettes (e-cig), etc.) compared to other racial and ethnic groups [4]. Despite nationally declining nicotine use, approximately 100,000 more AI/AN people began smoking over the last decade in the U.S [5]. Of concern is the rise in e-cig use among Indigenous youth which has outpaced use in other groups, with exclusive e-cig use estimated at 11.3% for Indigenous youth, compared to white youth at 7.1% [6].

Smoking is associated with several diseases (cancer, cardiovascular, and respiratory disease) that AI/AN people are already at higher risk for [7-9]. It is unknown how nicotine exposure impacted COVID-19 outcomes in this population, but we know AI/AN were disproportionately affected by the pandemic. Life expectancy for AI/AN dropped by 6.4 years from 2019 to 2021 (a 4-time greater decrease than in Non-Hispanic White populations) where they comprised 1.3% of total COVID-19 cases despite contributing to only 0.7% of the total US population [10-13]. Therefore, there is a great need to understand COVID-19, chronic health outcomes, and their association with nicotine exposure within the CRST. This was a critical need at the beginning of the pandemic due to the fact that the Tribe has been largely unsuccessful in changing active combustion tobacco use and behavior in the population while successfully protected population health from secondhand tobacco smoke exposure. Previous studies have found associations between nicotine and increased risk for severe COVID-19 outcomes, such as hospitalization [9, 14]. Additionally, newer e-cig products marketed as “tobacco free” products have been shown to reduce harm perception and increase likelihood of use [15]. Nicotine use behaviors, such as preferred nicotine concentration (%), and device characteristics, can modify chemical delivery and differentially affect health outcomes [16, 17].

The CRST is in a unique position to support policy development and detailed study of nicotine use because of decades-long partnerships with local researchers. Following advocacy from a multigenerational grassroots effort, the Canli (“Sacred Tobacco in Lakota language”) Coalition, the CRST Tribal Council took action to prevent harm from commercial tobacco and secondhand smoke by implementing the Smoke-Free Air Ordinance in 2015 and exposing e-cig companies’ illegal and predatory marketing on reservation land [2, 18]. In 2022, the CRST COVID-19 Wayakta-He?” (Are you on guard against COVID-19?) pilot study (5R21ES033119-02, PI Erdei) was launched to investigate how indoor exposures and nicotine use affect SARS-CoV-2 infection rates, and development of COVID-19 health outcomes. The specific purpose of this analysis was to describe the extent of self-reported COVID-19 and chronic disease outcomes with exposure to commercial nicotine by comparing exclusive e-cig users, cigarette users, dual e-cig/cigarette users, and nonusers among adult residents on the CRST. We hypothesized that nicotine exposure from both e-cig and combustion tobacco use would be associated with increased risk of negative COVID-19 and chronic health outcomes.

A recent study found that Northern Plains Tribes have a higher prevalence (around 50%) of smoking compared to Southwest Tribes, indicating that nicotine use differs by Tribe and geographical region [25]. While there are many similarities among AI/AN groups across the United States, it is important to investigate public health issues and support pandemic-related data collection and analyses on a local level due to geographic distinctions. The South Dakota Department of Tribal Relations estimated approximately 16,000 enrolled tribal members with the population living on the CRST Reservation land to be approximately 8600 in 2019 [26]. From those, approximately 4000 are children, leaving 4600 adults who were eligible to be enrolled on this study. It is likely that the population is greater considering the transient nature and employment dynamics of the CRST population and historical mistrust of the US government and non-participation in any census measurement [27]. However, using these conservative estimates, our study successfully captured nicotine use and health outcomes for approximately 12% of the total adult CRST population and was carried out to be community-based and representative of 21 out of 23 communities on the CRST Reservation land.

We found that more participants who were not AI/AN were non-nicotine users and in the upper income tertiles compared to other participants, which is consistent with previous findings [4]. The prevalence of nicotine use among Indigenous peoples is known to be higher compared to non-Hispanic White (NHW) Americans and is consistent with research done earlier on AI/AN nicotine use [28]. Previous studies have also found that income is highly stratified by race in the U.S. and AI/AN populations have lower representation in the top income groups than NHW [29]. Additionally, more nonusers and exclusive e-cig users were employed/working compared to cigarette smokers or dual users, which was similarly found in a previous study assessing tobacco use across US working adults [30].

Exclusive e-cig users were more likely to prefer dPODs compared to dual users who equally used dPODs and PODs. This is consistent with previous literature as dual users are reported to pick the type of delivery more by convenience/availability since they interchange between e-cigs and cigarettes [31]. Being older was positively associated with e-cig nicotine percentage. In a previous study from our group conducted on a majority NHW population, we found no significant association between age and nicotine percentage but a trend in the same direction [17]. We also found that being older was negatively associated with the use of PODs and dPODs compared to MODs, and this relationship has been reported in previous studies [32, 33]. Having a high school education/GED was positively associated with the use of dPODs and PODs and preference for flavors over unflavored nicotine. The total number of puffs per day for all nicotine use was positively associated with education status. It is possible that use is associated with higher education as an indicator of income and ability to afford nicotine products [34]. We found significant differences between puffs per day by nicotine delivery type, with dual users using their e-cig devices more than exclusive e-cig users. This indicates that e-cig users do not use nicotine at the same rates based on their preferred nicotine delivery.

The prevalence of heart disease in this study population (4.09%) is not in line with national statistics on AI/AN prevalence (11.0%) [35]. The prevalence of obesity in this population (14%) is much lower than the projections adjusted for self-report bias of 50% obesity prevalence in South Dakota [36]. High cholesterol (4.53%) and hypertension (23.8%) were also found to be reported at lower rates than the national averages of 34.5% for high cholesterol and 46.7% for hypertension [9, 37]. Rates of anemia were in line with previous literature in the US [38]. It is possible that health effects are underreported and under-diagnosed in this study due to lack of consistent primary care providers and steady access to healthcare in this population [39]. Despite federally recognized AI/AN populations having guaranteed access to primary healthcare through the federal Indian Health Service system, decades-long mistrust, and underfunded facilities with not enough consistent, dedicated, primary care provider base are still major problems in the majority of AI/AN communities [11]. Additionally, a previous study found that 1 in 6 AI/AN participants reported avoiding going to a healthcare professional, even if they are available locally, because of concerns of mistreatment and provider bias [40].

Nicotine use was negatively associated with reporting COVID-19, hypertension, and high cholesterol compared to no use. One study found that nicotine users with COPD avoid seeking medical care because of apprehension about being ridiculed of their nicotine dependence [41]. This could result in a lower propensity to seek medical care and diagnosis for COVID-19, hypertension, and high cholesterol. While we found that nicotine use was negatively associated with more severe COVID-19, the relationship between nicotine and severity of COVID-19 infection is currently not well-established. A recent review found that tobacco use had mixed associations with infection of COVID-19, although the overall weight of the evidence shows that nicotine use exacerbates COVID-19 health outcomes [42]. Other studies indicate that nicotine use may be associated with increased chance of an asymptomatic COVID-19 infection, or even reduced severity, compared to nonusers [42-46]. As tobacco smoke is a known immunosuppressant and a well-documented respiratory toxicant, it is possible that exposures to various cigarette-associated chemicals have direct downregulatory effect on the lung’s epithelial cytokine expression [47-49]. That could have also enhanced the occurrence of asymptomatic SARS-CoV-2 infections that further promoted viral particles’ spread especially in crowded, tobacco-using Tribal households.

Furthermore, it has been shown that cigarette and e-cig use in adults is associated with worse health literacy [50]. It is possible that lower health literacy compared to non-use, historical mistrust of healthcare professionals, and stigma against nicotine use may be contributing factors to the lower odds of having reported COVID-19 infection, less severe COVID-19 outcomes that are might underreported, lower rates of diagnosed hypertension, and high serum cholesterol levels. It is possible that in this rural, lower than average educational-achievement reporting community, higher education likely contributes to an increased access to healthier food choices, tobacco, and alcohol products due to affordability and increased opportunities to seek to medical care, even off the Reservation. Higher health literacy level overall contributes to more disease diagnoses [34, 51, 52].

This study has several limitations. Our recruitment occurred during COVID-19 restrictions, which meant no in-person interviews were carried out. Recruitment spanned 15 months, encompassing winter and varying incidence rates of COVID-19 and uptake of vaccines against severe COVID-19 disease. Because of this, there could have been temporal changes in the questionnaire answers from participants that we could not capture in a cross-sectional design or in our models. Additionally, participants could have displayed recall or social desirability bias when answering questions, as many may know MBIRI employees personally. When asking to self-report certain health outcomes in our questionnaire, it is possible that chronic disease information was underestimated, and the actual prevalence of such medical conditions could not be obtained. Finally, due to the unpredictable nature of relying on self-reported questionnaire information, we had to rely on imputation to complete our analyses concerning data on the number of cigarettes per day, even though our estimates were based strongly on previous CRST-driven measures and published information [18, 23].

Notwithstanding these limitations mostly imposed by the COVID-19 pandemic, our study has many strengths and provides valuable information on nicotine use, COVID-19 disease, and pandemic conditions influencing health, which are especially relevant in the rural U.S. To our knowledge, this study is the first to collect such information based on community-engaged recruitment/enrollment approaches and assess relationships between health and nicotine use on a large scale within this high-risk rural Tribal population. Our large sample size of over 500 adult participants is another strength; we were able to capture a large portion of adults on the CRST (over 12% of the total eligible). This study can be applicable to other Northern Plains region Tribes, with similar cultural and behavioral patterns and the community-based participatory research methods can be used widely across the United States in other Native communities or high-risk, rural populations. We were able to capture nuanced information on self-reported health outcomes, including COVID-19 disease information otherwise never captured in AI/AN groups, and nicotine use behaviors in a population that has been historically underrepresented and abused in research and targeted by the industry. This study was only possible through strong, community-driven approaches, culturally relevant enrollment and outreach works, and Native researchers’ dedication to its success.

We found trends in demographic characteristics with nicotine concentration, how soon after waking up they start smoking, total number of puffs per day, and use of e-cig devices. Nicotine users reported less high blood pressure, high cholesterol, and COVID-19 than non-nicotine users, which was unexpected. However, when infected with COVID-19, nicotine users reported less severe symptoms but longer recovery time that might be related to complex chemical toxicant exposure via combustion tobacco use and its immunosuppressive effects in the lung. We found the CRST community has different nicotine use behaviors depending on the type of nicotine. This study provides critical data on COVID-19, chronic disease outcomes, and exposure to commercial nicotine products. Results from this unique Tribal community–driven study with a large sample size (N = 562 participants from 289 households) will help understand the role environmental exposures played on increased COVID-19 mortality, help target public health interventions, and inform Tribal public health policies on emergency preparedness and exposure analyses. This information can be used by CRST leadership to understand the relationships between nicotine and health outcomes as this information has not been reported within the community before and could be directly applied to increase health literacy locally and beyond.

Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s40615-024-02145-3.