Promising Directions for Caries Prevention with American Indian and Alaska Native Children

 

Title:    Promising Directions for Caries Prevention with American Indian and Alaska Native Children

 

 

 

Authors:    Judith E.N. Albino, PhD¹

                   Valerie A. Orlando, RDH, MEd^1,2

 

 

 

Affiliations:  ¹Departments of Community and Behavioral Health, Colorado School of Public Health, and Oral and Craniofacial Biology, School of Dental Medicine, University of Colorado Denver.  ²Department of Surgical Dentistry, School of Dental Medicine, University of Colorado Denver.  

 

 

 

Address:  Please address all correspondence to: Judith Albino, PhD, President
Emerita, Professor, and Director, Center for Native Oral Health Research, Centers for American Indian and Alaska Native Health, Colorado School of Public Health, University of Colorado Denver, Mail Stop F800, Room 350, Nighthorse Campbell Native Health Building, 13055  E. 17th Avenue – Room 350,  Aurora, CO 80045  judith.albino@ucdenver.edu

 

 

 

 

 

 

 

 

 

 

 

 

Summary:

       Profound and consequential disparities in oral health persist for American Indians and Alaska Natives.  Decades of epidemiological studies have documented rates of Early Childhood Caries (ECC) among American Indian Children that are more than six times higher than those for white children, and three times higher than the rates for the general U.S. population.  While there is alarming need among this population, and there is clear evidence that dental caries can be prevented, successful programs for prevention are rare. This report will review caries trends among American Indian children and describe promising approaches that take into account culturally defined responses of AI/AN tribes and communities.  The work of the Center for Oral Health Disparities will be described, with its emphasis on community and behavioral strategies that have proven successful for working with AI/AN populations in areas of other health needs.  

 

 

Early Childhood Caries in American Indians/Alaska Natives               

Dental caries is the single most common chronic disease of childhood, affecting children worldwide of all social and ethnic groups.  Although advances in the understanding of oral disease etiology and prevention have led to a general decline in dental caries, these improvements have not benefitted all groups equally.  For example, overall caries experience among 2-5 year old children has shown a slight increase in the past two decades, and children from low income and ethnic minority households bear a disproportionate burden of disease.¹    Social, environmental, biological and behavioral factors all contribute to the chronic, complex nature of this disease and have impeded progress in reducing oral health disparities. 

During the last fifty years, large population-based surveys undertaken in the United States have documented the general trend of improving oral health status.  The most recent data from the National Health and Nutrition Examination Survey (NHANES) indicate that the prevalence of untreated dental caries in United States preschool children is approximately 19 percent.^{1, 2}  Despite substantial data from eight such large scale, population-based surveys^2-9 that reflect this trend, there is little information about the social and other variables that may lead to persistent and widening oral health disparities observed in certain populations.

Indigenous children of the United States exhibit a caries prevalence that is one of the highest in the world.¹⁰  Although reservation-dwelling individuals, who comprise more than 40 percent of Native populations,¹¹ were not included in the majority of the national surveys cited above, the Indian Health Service (IHS) has conducted oral health surveys,^12-14 as well as secondary analyses of clinical visit data,^15-19 for significant numbers of American Indians and Alaska Natives (AI/AN) in all 12 Indian Health Service regions.   Data on the prevalence of untreated decay among AI/AN children under age 5 reflect a disturbing increase from 40 percent in 1985,¹⁴ to 56 percent in 1991,¹² and up to 68 percent in 1999.¹³  Our understanding of this trend may be informed by early epidemiological research documenting a doubling of dental caries prevalence among American Indian school age children in the 30-year interval between the surveys by Klein and Palmer in 1929,²⁰ and subsequent epidemiologic studies by Ship in 1961.²¹   These data appear to support the thesis that the dental caries problem in American Indian children developed and increased in severity as a function of increased exposure to elements of white culture, and may confirm archaeological evidence for the detrimental effects of agricultural lifestyle on the dentition.^{20, 22-25} 

The oral health care of American Indians and Alaska Natives is the responsibility of the IHS.  This arrangement has evolved over time, based on a series of treaties between the United States Government and officially recognized Indian Nations, the common theme of which was that large tracts of land were ceded for certain benefits, including health care.  Since 1955, the IHS has provided for the majority of this obligation through a variety of agreements and contracts with tribes to provide health services to an estimated 1.9 million AI/AN people from more than 560 officially recognized tribes.²⁶  Current funding allocations to the IHS are sufficient to serve less than 50 percent of the dental needs of the eligible population,²⁷  and only 23 percent of IHS patients currently receive any dental services at all.²⁸   By contrast, mandatory health spending for public programs such as Medicaid has outpaced discretionary funding of the IHS by 250 percent.²⁹  In 2008, per capita spending for Medicare and  Medicaid beneficiaries was just over $7400, and for IHS, only $2300 per person.²⁶  Moreover, oral health spending represents a very small fraction of this figure, recently documented as less than 4 percent of overall health expenditures.  Although pediatric dental care, including preventive services, traditionally has been a priority for most IHS service areas, the resources allocated for this purpose are extremely limited in light of the overwhelming need.  

Interventions for Early Childhood Caries                                  

Given the uneven distribution of disease, investigators have focused increased attention on disease management strategies that target higher risk individuals and groups.³⁰   If, as Featherstone proposed, dental caries outcomes are determined by the relative balance between an individual’s risk and protective factors, then caries prevention can most practicably be achieved by reducing pathologic risks and increasing protective factors.³¹   This may not be a simple task, however, given the chronic nature of the disease and the limited evidence base for many of the preventive practices designed to address ECC.  Three primary routes have been recognized for caries prevention: community efforts (such as education, public programs, and fluoridation), professional efforts (treatment or therapies requiring professional intervention) and home care (hygiene and dentifrice use) ³².      

Parent and child dental health education has been described in much of the literature as generally ineffective in terms of outcomes such as reducing bacterial load or overall caries rates.^33-36  A study of one such dental health education effort among American Indian parents of preschoolers found no effect on oral hygiene behaviors.³⁷  And a more recent systematic review of the dental health education literature found very few valid intervention studies and insufficient evidence for the effects of educational programs on long-term behavior change or reductions in caries incidence.^{32, 35-43}   

Among the clinical interventions for caries prevention, the use of fluorides demonstrates the strongest evidence base and most predictable success.^44-46  Although community water fluoridation is safe, effective, and socially equitable as a public health measure for reducing the incidence of dental decay up to 40 percent in children and adults, this approach continues to meet with resistance in some quarters.  Opponents typically cite the high cost of upgrading or maintaining outdated water systems to enable fluoridation in rural communities.   Despite the known benefit of water fluoridation, the number of fluoridated water systems in Indian country has declined steadily over the past two decades.  The most recent estimates indicate that fewer than 20 percent of community water systems on reservations are optimally fluoridated.⁴⁷

According to the National Institute of Dental and Craniofacial Research (NIDCR), additional professional and individual measures, including the use of fluoride mouth rinses, gels, dentifrices, and dietary supplements, are important means of preventing dental caries.⁴⁸  Fluoride varnish has been used extensively in European countries since the mid 20^th century.  Since gaining approval in the United States in 1991, fluoride varnish has been more thoroughly investigated for its usefulness in caries prevention and control, adding to the growing body of international evidence.  Findings from systematic reviews and meta-analyses of randomized controlled trials suggest that caries prevention in primary teeth reaches approximately 33 percent with the use of fluoride varnish at 6 month intervals.^{30, 32, 49-51}  Fluoride supplements in the form of vitamins and prescribed supplements have been estimated to provide a 20 percent reduction in caries—about half the benefit of community water fluoridation.⁵²  However, many of these measures are limited in their scope and primarily benefit those individuals who have the financial means to assure access to regular professional oral health care services. 

Recent research on natural polyols and chemotherapeutic agents has also shown promise for caries inhibition; these agents include sorbitol, xylitol, and chlorhexidine in various preparations of gel, chewing gum and syrup.^53-57  These caries preventive agents have not been widely used, however, and not all are commercially available.    Studies using xylitol and chlorhexidine for the prevention of ECC are have typically focused on antimicrobial suppression of maternal oral flora in an attempt to reduce vertical transmission of caries causing bacteria to the infant.  One such project sought to deliver oral chlorhexidine and xylitol chewing gum to pregnant mothers in rural Alaska to determine if these interventions could reduce vertical transmission of caries.⁵⁸  Unfortunately, the project team encountered significant barriers; a lack of understanding of cultural differences and familiarity with local cultural traditions resulted in problems with staff retention and subject recruitment to such a degree that the study ultimately had to be abandoned.   The investigators subsequently wrote about the importance of forging trusting relationships with local tribal leaders and community members as an essential element in  gaining access to, and  working with, these communities.⁵⁸  These are important lessons for any group working with AI/AN tribes and communities.

 

American Indian Interventions                                             

While sufficient evidence exists to document the poor oral health status of AI/AN children, there have been very few reports of interventions.  Holve documented the effects of fluoride varnish applications as part of routine preventive well-child care at an IHS clinic in the Southwestern United States.⁵⁹   Dentists applied fluoride varnish during well-child visits scheduled for children at ages 9, 12, 15, 18 and 24 months, and parents received dental advice appropriate to the age of their children.  These children subsequently received dental examinations at age 3, upon entering the local Head Start program.  The intervention was not standardized for research purposes, and the only control was a historical comparison/control group.  Nonetheless, those children who had received 4 or more fluoride varnish treatments exhibited a mean decayed, missing, and filled tooth surfaces (dmfs) score of 15, compared to a mean score of 23.6 for children who had not received any fluoride applications.⁵⁹  The 35 percent lower caries incidence for children in the program was statistically significant.⁵⁹   There was no report of non-clinical outcome measures, nor were the investigators able to separately evaluate the behavioral or motivational effects of oral health advice delivered at well-child visits. 

Bruerd and colleagues⁶⁰ reported a community-based intervention to prevent ECC in Native American children that appeared to result in positive oral health outcomes.  Implemented from 1986–1989, the project’s aim was to determine whether community-based health education would result in lower prevalence of decay among AI/AN children.⁶¹  Twelve Head Start Early Childhood Education programs received various levels of training in oral health promotion and planned multidisciplinary educational interventions for individuals and within the community.  The two major components of the program were one-to-one counseling sessions for parents and caregivers delivered by trained Head Start staff, and community-wide campaigns designed to increase awareness.  In 1990, the centralized funding and technical support efforts for the program were formally discontinued, but programs were encouraged to continue health-promotion activities.  In 1994, a follow-up assessment of the program activity and the prevalence of caries among enrolled children was undertaken by the US Health and Human Services agencies that initiated the effort.  For the 12 sites, the average prevalence of decay in the post-program cohort was 25 percent lower after four years; at the five sites that continued to implement the program for an additional four years, the difference was 38 percent.⁶⁰  The project did not deliver any direct clinical prevention services, there was no control or comparison group, and effectiveness was assessed primarily in terms of program evaluation and acceptability.  The caries outcome measure was a temporal difference in the prevalence among groups of children, observing caries in the baseline cohort of 3-5 year olds as compared to the post program cohort of children the same age, rather than a longitudinal reduction in the incidence of new caries.

An innovative ECC prevention and early intervention approach was piloted by Quissell et al. in 2002.  This project, referred to as the Community Oral Health Specialist (COHS) program, was designed to meet the needs of a Northern Plains Tribe.  The two main objectives of the COHS program were to make preventive oral health services av