Preventing Caries in American Indian Children: Lost Battle or New Hope?

Abstract

Knowledge Transfer Statement: Preventing early childhood caries in American Indian children has proved to be an unexpectedly challenging goal. Biological and behavioral variables, as well as parental psychosocial characteristics and experiences, suggest new routes for understanding and mitigating the progress of disease. We provide our reflections after a decade of studying these issues in collaboration with tribal communities.

Recent outcomes of intense efforts to prevent oral disease among American Indian (AI) children have proved perplexing and distressing. Two clinical trials conducted by the Center for Native Oral Health Research at the University of Colorado Anschutz Medical Campus provide a context for understanding the ongoing challenges and importance of this work.

Although theoretically preventable, early childhood caries (ECC) is a critical and persistent health issue among ethnic minority and lower-income children. This challenge is most striking among AI children; the rates and severity of ECC in some US tribal populations are among the highest reported anywhere in the world. Lamentably, the problem seems virtually impervious to methods and approaches that have proven successful elsewhere.

A Head Start Caries Prevention Trial

An average baseline caries (dmfs) score of 21.3 was found for 1,106 3- to 4-year-old AI children in 52 Head Start classrooms enrolled in a cluster randomized trial of a caries prevention program on a large Southwestern reservation (Braun et al. 2016). This is 5 to 6 times higher than the average for the general US population.

The challenge of slowing such rampant caries progression was enormous; we used a community-based participatory framework that involved tribal representatives in designing culturally appropriate health promotion activities that were then delivered by tribal members trained in basic oral health concepts and recommended home care practices. These community oral health specialists (COHS) provided toothpaste and brushes for all family members, quarterly fluoride varnish applications in the Head Start centers, and referrals for dental care—as well as community outreach and education. To meet clinical trial requirements for adherence to standardized approaches, all parent meetings were held in a public location and participants were provided identical opportunities to work with the COHS.

Although reservation residents have access to Indian Health Service (IHS) dental care, families often live remotely, have limited transportation options, and may seek care only for acute problems. IHS clinics are chronically underfunded and understaffed, waiting lists are long, and consequently, there sometimes is little focus on prevention. Our program offered an intense focus on prevention to address this challenge.

Despite the obvious need for prevention and our emphasis on culturally sensitive intervention, study results revealed that, after 2 y, caries experience had advanced to 96.6% for children in the intervention group and 98.2% for those in the control group, with average dmfs scores of 32.8 and 33.6, respectively. In reporting our work, we speculated that beginning at age 3 might be too late, that the disease among these children may already be so advanced as to be beyond even intense prevention strategies.

Parental Factors in ECC Prevention

We carefully examined all study data, including the effects of mediators and moderatos, in the hope that a closer look would reveal more. Most children received the maximum 4 fluoride varnishes each year, but parental program participation was low. The average number of parent events attended was 1.3 out of 4 offered; only 36.5% of parents attended more than 1, and 35% attended none (Braun et al. 2016). Any participation at all seemed to create advantages, however; the caries increment was significantly smaller for children whose parents participated in even 1 educational session. These findings led us to speculate that parental characteristics might provide additional clues about how best to support family efforts to prevent ECC.

In an earlier examination of baseline data for these parent-child dyads, we found no sociodemographic differences between the parents of the 10.7% of children who were caries free and the vast majority who had caries (Albino et al. 2014). However, we did find that parents of caries-free children viewed oral health as more important, had more oral health knowledge, and reported higher adherence to caries-preventing behaviors. They were more likely to have internal oral health locus of control (OHLOC) orientations, to perceive their children as less susceptible to caries, and to perceive fewer barriers to prevention; they had higher sense of coherence scores and lower levels of personal distress and community-related stress. In other words, children had better oral health when their parents were focused on that issue; had some knowledge, skills, and attitudes with which to constructively deal with the challenge; and were coping reasonably well within communities characterized by pervasive poverty and related health and social challenges. Although certain parental knowledge, behaviors, and attitudes appeared to be protective of children’s oral health at an early age, this advantage apparently deteriorated over the preschool years.

Psychosocial Variables and Caries Resistance

In further reviewing outcomes data, we found that lower increases in caries were, in fact, associated with higher internal OHLOC in the intervention group. We also noted with optimism that parents who had external OHLOC demonstrated greater gains in both knowledge and behaviors supportive of oral health and that parents with lower oral health literacy showed greater growth in oral health knowledge. However, parents who perceived more barriers to recommended behaviors had worse parental oral health and had children with higher caries, as well as worse paediatric oral health quality of life.

Parental and psychosocial factors support the idea that parents who perceive themselves as having some control over their children’s oral health can actually influence the course of disease; on the other hand, those who are focused on the barriers—perhaps influenced by futility grounded in a history of poor oral health in themselves—may be less likely to positively influence the course of their children’s disease.

Beginning Prevention Earlier

Again, the results of our work lead us to believe that ECC begins earlier in AI children and progresses at an extremely rapid rate, suggesting the need for earlier intervention. An opportunity to test the impact of earlier intervention came with the recent, initial release of data from a second clinical trial.

This trial of early intervention with mothers and newborns has just been completed on a Northern Plains reservation; we used motivational interviewing (MI) to provide new mothers with knowledge and tools for preventing caries in their children. Six hundred mothers of newborns were enrolled in the program, and they and their children were followed for 36 mo, with caries examinations conducted at 12, 24, and 36 mo. Half were assigned to the MI intervention and half to an enhanced community services control. Intervention group participants met with a trained MI specialist every 6 mo for 2 y. The MI approach was adapted to the AI population, with the support of an AI consultant with this special expertise, and sessions were conducted in participants’ homes or another preferred location. Despite implementing a highly personalized intervention, initial results show no treatment effects when dmfs scores are compared for children in the 2 treatment groups.

Reflecting further on the results of both studies, we noted a mean dmfs of only 10.3 for Northern Plains tribal children at the age of 3 y (poststudy), compared with a much higher baseline mean of 21.3 in the Southwestern tribal children, who were 3 y when that study began. This difference could be a function of the earlier start of the intervention with the Northern Plains tribe, and we are continuing to examine the data related to this question, as well as other possible explanations for the results.

Discussion

Considering the results of our work conducted over 10 y, we continue to ponder what we might do differently to achieve the better oral health that seems so elusive for AI children. Although we suggested that the answers lie in beginning prevention earlier, we now believe that other ways of looking at this challenge must be sought. It is likely that we will need to incorporate more than 1 perspective.

Biological Differences

It has been suggested that the oral cavities of AI children are colonized by Streptococcus mutans earlier than in the general population (Lynch et al. 2015). The traditional “window of infectivity” is 19 to 31 mo, but in AI children, S. mutans colonization is seen by 16 mo (Caufield et al. 2012). This “early acquisition” has been associated with the development of ECC. Earlier tooth eruption patterns also have been documented in AI children, suggesting that these children have more time in their early years to develop caries (Warren et al. 2016). Finally, at least 1 study has found that, in addition to the expected vertical transmission of S. mutans, AI children show still higher levels of horizontal transmission, which is associated with oral sharing of utensils or other objects and food (Lynch et al. 2015).

Another perspective on the high prevalence of caries in AI communities suggests that prenatal stresses could result in enamel hypoplasia, creating vulnerability to early colonization of S. mutans. Diets that typically are high in sugary foods—common in reservation communities—would exacerbate these conditions, resulting in still higher risk factors for ECC development (Caufield et al. 2012). Although the implications of these studies require full confirmation, the findings seem to support our contention that efforts must begin very early if we are to affect prevention.

Psychosocial Determinants and Inverse Case Law

Even if we discover that earlier prevention efforts will make a difference, we will likely continue to grapple with individual differences in parental response to prevention programs. We are intrigued by descriptions of the theory of “inverse case law” applied to prevention. This concept suggests “that individuals and groups who are in minor need of an intervention may benefit more from it than those who are in major need” (Watts 2002).

Put another way, those who are in less need of an intervention may be in less need because they have resources—personal, economic, or social—that allow them to recognize and address the health issue to at least some extent. Those who are in greater need of the intervention, on the other hand, have not recognized the challenge and/or do not have resources with which to address it. The former group is likely to benefit considerably and the latter much less. These differences may be at work in the AI communities we have studied, where results continue to fall short of expectations.

Several factors influence the “inverse case” relationship, including socioeconomic status, race/ethnicity, insurance, location of residence, comorbidities, low oral health literacy, psychosocial stress, and fatalism (Petti 2010). Individuals who are fatalistic, or have beliefs that they are unable to influence the oral health of their children, may have children with greater need and also may not respond positively to prevention interventions. This theory of inverse case law could be used to describe what we saw in the study of caries-active and caries-free children and in the outcomes of the Head Start study.

When we look at parent participation in the Head Start prevention program, this explanation is particularly apt. Parental external and chance OHLOC, low health literacy, and fatalistic ideas about oral health appeared to be negatively related to parental participation in the ECC interventions, yet it stands to reason that those parents who did not participate might be the ones who would most need to access help for their children’s oral health.

As we continue to study the onset and progression of caries in young children, we also need to examine behavioral and psychosocial characteristics of their parents, with consideration for the influence these variables may have on the use of knowledge and tools for prevention. Of course, the goal is more than understanding why some are more likely to engage in oral health–enhancing behaviors for their children; ultimately, we must be able to make a difference in the circumstances that give rise to very different capacities to benefit from prevention programs. This means designing programs that take into consideration the full life circumstances of individuals involved. From this perspective, a program for improving children’s oral health might best do its work, for example, if offered from the perspective of building parental self-efficacy through self-skills and family management skills. The AI population, unfortunately, experiences extremes in disparities related to multiple chronic health concerns, suggesting that the greatest benefits may accrue from approaches such as these that will address the need for parenting skills applied across this broader array of health challenges.

Author Contributions

J. Albino, T.S. Batliner, T. Tiwari, contributed to conception, design, data acquisition, analysis, and interpretation, drafted and critically revised the manuscript. All authors gave final approval and agree to be accountable for all aspects of the work.