EJE 2 : ARJONA EMPRENDEDORA, PRODUCTIVA Y SOSTENIBLE

The most appropriate response to these data is to prevent edentulism in this group (Mac Giolla Phadraig et al., 2015c). With regard to the 5,000 adults with ID who have neither teeth nor dentures in Ireland, it is essential that services ensure informed decisions by

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empowered patients. Accessible denture processing skills are also necessary. In Ireland, where the bulk of care to older adults with ID is delivered by the pediatric-oriented Public Dental Services (PA Consulting Group, 2010), this may necessitate reorientation of dental services and/or up-skilling of service providers to respond to the needs of this emerging cohort. There is a similar argument for increasing special care training for undergraduate dentists and clinical dental technologists to maximise this cohort’s access to appropriate dental services. The provision of implant-retained prostheses could be also considered. However, such services are potentially expensive. The McGill Statement (Feine et al., 2002, Thomason et al., 2009) recognizes two-implant mandibular removable overdentures as a minimum treatment for edentulism. To provide this minimum standard of care for this population, at a conservative cost of €5000 per person, would cost €25,000,000 or a third of the national budget for the Public Dental Service. However, a demand led service is unlikely to cost anywhere near this as one study suggests: Targeted services offering implant-retained prostheses to edentulous older adults with disabilities in Scandinavia had extremely low uptake (Brahm et al., 2009). In addition, there are a number of contraindications to prostheses with or without implant support which will likely further reduce the numbers likely to avail of such care. This includes conditions such as poor oral hygiene, inability to tolerate the process of construction, inability to wear prosthetics due to poor neuromuscular control, complex medical history, extensive resorption of prosthesis bearing tissues as seen in those with periodontal disease or chronic edentulism.

5.4.5 Limitations

The results of this study should be considered in the context of its limitations. This study used self-report measures of denture wear with a risk of misattribution bias: participants may not correctly describe their denture wear status. The current design did not allow the research team to verify dentate status and the wear of dentures. We plan to measure the validity of such self-reported measures in Wave 4 of IDS-TILDA. Secondly, proxies were often used to report both dentate status and denture wear. The inclusion of proxy response was important so as those with greatest dependency were included and their experiences captured in the overall study. Without this, they would have been excluded leading to a skewed picture of this population. However, this means that one person is responding on behalf or in tandem with another and the degree to which this

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communication is influenced by the proxy must be variable from respondent to respondent. This is a possible confound, which is why it was included in the study as a DV. In fact it was found to be a significant predictor of denture wear, which highlights the importance of supported communication for this group. Additionally, participants may not remember the reasons why they stopped wearing dentures: a recall bias. Some respondents relied on others to help them answer these questions, and this reliance on proxy respondents may influence the findings reported. Lastly, this data do not suggest that CRDs are a “best option” for all edentulous older adults with ID, rather they illustrate that clinicians must actively involve the patient in decision making and assessment regarding denture therapy so as the best choice for each patient can be agreed.

5.5 Conclusion

While there is a high normative need for prosthodontic rehabilitation among the older adult cohort with ID, the expressed need is low. The current study found that older edentulous people with ID do not appear to want prostheses. Extra steps might be needed to empower edentulous patients and ensure that consent is truly informed when they opt for or decline denture therapy. While this study highlights some issues in the imbalance between expressed and normative need, the reasons for low demand are still somewhat unclear. More research is needed, specifically studying factors, which influence decision making when planning care for edentulous older adults with ID. There is also a need to understand the impact of failing to restore oral function for this population. The next chapter explores the benefit of wearing dentures of this cohort.

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Chapter 6 Total tooth loss is a risk factor for difficulty eating

for older adults with intellectual disabilities – only if

untreated.

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Summary of Chapter 6

Purpose This chapter is the third and final chapter that explores total tooth loss and its treatment with complete removable dentures among adults with intellectual disabilities in Ireland. This chapter aims to measure the functional impact of edentulism and its management on older adults with ID by quantifying the predictive value of dentate status on difficulty eating.

Methods Cross-sectional survey data from Wave 2 of the IDS-TILDA study were

entered into a multiple logistic regression model testing the relationship between the dependent variable, Difficulty eating, and one variable, Dentate status, with the effect of other independent variables statistically eliminated. This model offered the best fit of the data, based on Akaike’s information criterion (AIC). The predictive value of the overall model was tested using a ROC Curve and Area Under the Curve Statistic.

Results Of the 692 participants, 506 had some teeth (Group 1), 57 had no teeth and reported wearing complete removable dentures (Group 2) and 129 had no teeth or dentures (Group 3). A parsimonious regression model was developed including 406 responses. Using this model, compared to Group 1, it was found that the odds of difficulty eating was twice as great (OR=2.01, 95%CI=1.02-4.03) among people without teeth or dentures (Group 3). Conversely, edentulous participants who had dentures (Group 2) had far lower odds (OR =0.21, 95%CI=0.06-0.64) of reporting difficulty eating compared with those with natural teeth (Group 1). The overall model showed good discrimination, according to AUC statistic.

Conclusions The study findings confirm that, for adults with ID, toothlessness is predictive of difficulty eating only when untreated. When treated, the risk of difficulty eating is actually reduced dramatically, even compared to those who report having natural teeth. Missing teeth should be replaced for edentulous adults with ID. Dental assessment should also be incorporated into the assessment of eating difficulties among adults with ID, especially as they age.

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6.1 Introduction 6.1.1 Introduction

In the previous chapter, it was clear that people with ID do not always receive functional replacement of missing teeth when they become edentulous, something that people with ID do not demand. Indeed it seems that the option of such replacements is not presented to people with ID in a meaningful way(Mac Giolla Phadraig et al., 2016). Given that dentists, applying principles of evidence based practice, will theoretically, frame the discourse for those who have capacity, and lead best interest decisions for patients who lack capacity, evidence is needed as to the benefits, or indeed not, of oral rehabilitation specific to this group. Therefore, this chapter assesses a basic function of dentition: eating, and specifically, whether total tooth loss, restored or unrestored, is a risk factor for difficulty eating among this population.

6.1.2 Background

Dental caries (tooth decay), occurs when dietary carbohydrates are fermented by bacteria in dental plaque causing demineralisation, cavitation, inflammation and infection of teeth. Periodontitis (gum disease) occurs when the gum and bone surrounding the teeth (periodontal tissues) become inflamed and leads to bone resorption, looseness and eventually loss of teeth. The cumulative outcome of these processes, and their mismanagement, is total tooth loss (edentulism).

The number and distribution of teeth affects chewing efficiency (Schimmel et al., 2015, Walls and Steele, 2004), an essential sensorimotor attribute for preparation of food for swallowing (van der Bilt et al., 2006). For people with no teeth at all, this may lead to sub-optimum food choice, food avoidance and, possibly, nutrient deficiencies (Moynihan et al., 2009). Walls and Steele found, in their review of the literature, that edentulism affects chewing efficiency, but more importantly it limits food choice, selection and preparation, especially of fruit and vegetables, which are rich in Vitamin C and fibre (Walls and Steele, 2004). In fact, nutritional changes like these (along with inflammation and infection) are seen as an important biological vehicle behind the relationship between tooth loss and mortality (Polzer et al., 2010).

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People with no teeth present with chewing difficulty (Walls and Steele, 2004, Slade et al., 1996) and providing dentures alone may not lead to significant improvement in dietary choice or nutritional status (Moynihan, 2005, Sheiham and Steele, 2001). Denture wear offers functional replacement of teeth and is the norm for older edentulous populations without ID (Mac Giolla Phadraig et al., 2015c, Slade et al., 1996). Complete dentures have been shown to reduce the health (Polzer et al., 2010) and nutritional impact of edentulism by improving diet, and reducing both malnutrition and obesity (Han and Kim, 2016, Saarela et al., 2014, Lamy et al., 1999, Han and Kim, 2016). Yet they also present a challenge when chewing (Walls and Steele, 2004, Slade et al., 1996) and may not lead to significant improvement in dietary choice or nutritional status with denture therapy alone (Moynihan, 2005, Sheiham and Steele, 2001). In total, the evidence suggests that total tooth loss leads to difficulty eating in the older general population, as expressed through dietary choice and food modification, quality of life and nutritional outcomes. It appears that denture wear may reduce difficulty eating, though this picture is somewhat unclear. The population with intellectual disabilities (ID) are aging (Bittles et al., 2002) and experience edentulism to a greater extent and at an earlier age, than the general population (Crowley et al., 2005, Whyman et al., 1995, Hinchliffe et al., 1988, Morgan et al., 2012, Mac Giolla Phadraig et al., 2015c). However, unlike their counterparts in the general population, they are very unlikely to wear complete dentures when they become edentulous (Costello, 1990, Naidu et al., 2001, Hinchliffe et al., 1988, Cumella et al., 2000). One study found people with ID to be twelve times less likely to wear dentures when they lose their teeth (Mac Giolla Phadraig et al., 2015c). How people with ID come to this decision, to not wear dentures, is unclear and there is a question as to whether they are supported to make informed decisions about dentures. A better understanding of the impact of denture wear on function, such as on eating, for people with ID would increase evidence to support informed and empowered treatment choices (Mac Giolla Phadraig et al., 2016). However, the relationship of dentition status, denture wear and difficulty eating among this population remains unclear.

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The lack of clarity may be in part due to the multidimensional nature of the eating difficulty in this population. Eating and swallowing are complex behaviours involving volitional and reflexive activities of more than 30 nerves and muscles (Matsuo and Palmer, 2008) and among people with ID particularly, the term extends far beyond masticatory dysfunction, referring to neural impairment affecting chewing and swallowing, psychogenic vomiting, reflux, regurgitation, rumination, faddiness/refusal, hyperphagia, pica, binge eating, food stealing and many more (Clark and Griffiths, 2008, Gravestock, 2000). Put another way, for people with ID, the concept of difficulty eating covers an array of specific structural and functional impairments including food selectivity, feeding skills deficits, food refusal, risk of aspiration or behaviour problems (Gal et al., 2011, Matson and Kuhn, 2001). When researchers consider difficulty chewing specifically, among children with disabilities and populations often affected by ID, it seems to be a significant contributor to such eating difficulties (Sjögreen et al., 2015, Seiverling et al., 2011).

There a need to understand the complex underlying phenomena that contribute to eating disorders among people with ID (Gravestock, 2000). This is because difficulty eating may influence the choice of residence that adults with ID live in (Matson et al., 2006) and is predictive of dependency during meals (Ball et al., 2012), often making meal times lengthy and more difficult (Chadwick and Jolliffe, 2009). Another reason is that eating difficulties pose serious health risks. These include aspiration, poisoning, malnutrition (Matson and Kuhn, 2001) and asphyxiation (Samuels and Chadwick, 2006). Research supports the assumption that a functioning dentition can reduce the risk of asphyxiation in older adult populations, even in those without an ID (Kikutani et al.). . Respiratory infections arising from aspiration are common (Perez et al., 2015) and a major cause of death in adults with ID (Tyrer and McGrother, 2009). Difficulty eating can even predict death among adults with ID (Heslop et al.).

Until now there have been no large, epidemiological studies to test the assumption that edentulism in adults with ID leads to difficulty eating or that dentures restore this function. Understanding the role of total tooth loss may lead to better assessment and management of difficulty eating in this population. There is also a need for evidence

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regarding the functional impact of treating and not treating edentulism to determine if denture therapy is beneficial (Mac Giolla Phadraig et al., 2016). ,Therefore, this study aims to test whether edentulism is a risk factor for difficulty eating and whether replacement of total tooth loss reduces any functional impact.

6.1.3 Research questions

Is total tooth loss predictive of difficulty eating in adults with ID, with and without complete denture wear?

6.2 Methods 6.2.1 Design

This is an observational study based on secondary analyses of the cross-sectional survey data from the Intellectual Disability Supplement to The Irish Longitudinal Study on Ageing (IDS-TILDA). The latter is a multi-wave longitudinal study exploring the ageing profile, physical and behavioural health, health services needs, psychological health, social networks, living situations and community participation of older adults with ID in Ireland (McCarron et al., 2014).

6.2.2 Ethics statement

This study complies with the ethical standards and laws applicable in Ireland. This study received ethical approval from the Faculty of Health Sciences Research Ethics Committee in Trinity College Dublin and all participating services.