Understanding Dysphagia in Dementia: The Present and the Future

Effects of healthy aging on tongue-jaw kinematics during feeding behavior in rhesus macaques

Several age-related oral health problems have been associated with neurodegenerative diseases such as Alzheimer's Disease (AD), yet how oromotor dysfunction in healthy aging differ from those found in pathological aging is still unknown. This is partly because changes in the cortical and biomechanical ("neuromechanical") control of oromotor behavior in healthy aging are poorly understood. To this end, we investigated the natural feeding behavior of young and aged rhesus macaques (Macaca mulatta) to understand the age-related differences in tongue and jaw kinematics. We tracked tongue and jaw movements in 3D using high-resolution biplanar videoradiography and X-ray Reconstruction of Moving Morphology (XROMM). Older subjects exhibited a reduced stereotypy in tongue movements during chews and a greater lag in tongue movements relative to jaw movements compared to younger subjects. Overall, our findings reveal age-related changes in tongue and jaw kinematics, which may indicate impaired tongue-jaw coordination. Our results have important implications for the discovery of potential neuromechanical biomarkers for early diagnosis of AD.

The Oropharyngeal Dysphagia Screening Test for Patients and Professionals: Validation in Cognitive Impairment and in Severe Mental Illness

Dysphagia is a symptom that appears with high prevalence in persons diagnosed with dementia, intellectual disability, or severe mental illness. Risk of aspiration pneumonia or even death is very high in these populations. However, screening for dysphagia risk in these patients is complicated by the fact that most of them suffer from cognitive impairments and behavioral manifestations that hinder the assessment process using the existing screening tests. The aim of this study was to validate the Oropharyngeal Dysphagia Screening Test for Patients and Professionals, in patients with cognitive impairment (dementia/intellectual disability) or with severe mental illness (schizophrenia and other psychotic disorders, bipolar disorder, or major depressive disorder). For this purpose, 148 institutionalized patients were evaluated by professionals responsible for their food intake. The Oropharyngeal Dysphagia Screening Test for Patients and Professionals was used to assess its validity in screening for oropharyngeal dysphagia in patients with cognitive impairments and in patients with severe mental illness. Also, the Eating Assessment Tool-10 and the Swallowing Disturbance Questionnaire were used for convergent reliability procedures. Four comparison groups were established: patients with cognitive impairment with and without oropharyngeal dysphagia, and patients with severe mental illness with and without oropharyngeal dysphagia. Results from the Oropharyngeal Dysphagia Screening Test for Patients and Professionals adequately distinguished between groups with and without dysphagia, in addition to presenting adequate levels of convergent validity and reliability. These results were obtained from other-reports (professionals responsible for patients' food intake), using a simple, quickly applied test that does not require the use of food in patients with an altered cognitive state or with severe mental illness. With this study we expand the validity of the Oropharyngeal Dysphagia Screening Test for Patients and Professionals in populations with severe cognitive deficits and mental illness in which there is a great deficiency of oropharyngeal dysphagia screening instruments.

Dysphagia and Functional Limitations Among Adults in the United States: Findings from the 2022 National Health Interview Survey

Dysphagia or swallowing dysfunction is associated with reduced quality of life and poor long term outcomes. While standard dysphagia treatment focuses on improving swallowing function, it is not clear if people with dysphagia also have difficulties performing daily tasks. This study aimed to determine if individuals with dysphagia had difficulties with participating in daily tasks requiring physical function, as compared to those with no dysphagia. We conducted a secondary data analysis using the responses of 24,107 adults aged 18 years or older who completed the 2022 National Health Interview Survey. The independent variable was report of swallowing problem during the past 12 months, and the dependent variables were report of difficulty in physical function tasks (e.g., self-care, mobility, working, social participation). We utilized propensity score methods to balance demographic and clinical variables between groups, and examined if individuals with dysphagia had more difficulties with the physical function tasks. The propensity score methods balanced the demographic and clinical variables (absolute standardized differences < 0.1). People with dysphagia had significantly higher odds ratios (ranged from 1.23 to 1.70, all p < 0.05) of having difficulties in physical function tasks than those without dysphagia. The findings revealed an association between experiencing dysphagia and encountering difficulties in self-care, mobility, working, and social participation in the general adult population in the US. Results of our study indicate that during the course of rehabilitation, healthcare professionals should consider the potential impact of dysphagia symptoms on clients' ability to partake in independent activities in their community settings.

Exploratory analysis of swallowing behaviour in community-dwelling older adults using a wearable device: Differences by age and ingestant under different task loads

Objective

To develop a new method of evaluating swallowing behaviour.

Methods

Sixty-nine healthy participants were divided into a younger (16 males and 16 females, mean age 39.09 ± 12.16 years) and older (18 males and 19 females, mean age 71.43 ± 5.50 years) group. The participants ingested water and yoghurt twice (directed and free swallowing) at rest and after performing simple daily life tasks (calculation and exercise). To measure swallowing frequency, we employed a smartphone-based, portable and neck-worn swallowing-sound-monitoring device. This device monitors swallowing behaviour continuously by collecting biological sounds from the neck without imposing behavioural restrictions. A neural network model of swallowing sound identification by deep learning was used for the subsequent evaluation. This device was used to obtain two types of saliva-swallowing sounds associated with different ingestants, at rest and after performing a stimulating task. Furthermore, we assessed the associated subjective psychological states.

Results

The younger group showed a higher directed swallowing frequency (for both water and yoghurt) than the older group did. Regarding the type of ingestant, the swallowing frequency for yoghurt was higher during free swallowing in both the young and the older groups. 'Feeling calm' was reported significantly more often in the older group after swallowing yoghurt following exercise.

Conclusions

Swallowing status in daily life was measured non-invasively using a wearable mobile device. It is important to consider the type of ingestant, daily living activities, and age when assessing swallowing.

Identification of eating, drinking and swallowing difficulties for people living with early-stage dementia: A systematic review

BACKGROUND

The prevalence of dementia is increasing, bringing a range of challenges, such as eating, drinking and swallowing (EDS) difficulties, that are associated with aspiration, which can be fatal. Early identification of EDS difficulty in early-stage dementia could prevent complications, but reliable indicators are needed to help develop pathways to support the diagnosis. Previous reviews of this area require updating.

AIMS

To identify reliable and clinically measurable indicators of EDS difficulty used in early-stage dementia.

METHODS & PROCEDURES

A systematic search was conducted using common databases (MEDLINE, EMBASE and PsychInfo). Articles reporting indicators of EDS difficulty in early-stage dementia or mild cognitive impairment were included. The reliability of included studies was critically appraised using the risk of bias tools. Study outcomes were narratively reviewed by considering the reliability, clinical measurability and applicability of EDS indicators to early-stage dementia.

OUTCOMES & RESULTS

Initial searches returned 2443 articles. After removing duplicates, limiting to English language and human studies, 1589 articles remained. After reviewing titles, 60 abstracts were reviewed, yielding 18 full-text articles. A total of 12 articles were excluded that did not report at least one indicator of EDS difficulty in early-stage dementia, or where the reported association was not strong. Six included studies that reported eight indicators of EDS difficulty in early-stage dementia (four studies including people with Alzheimer's disease). On the balance of measurability, reliability and applicability, the most promising indicators of EDS difficulty were: delayed oral transit, rinsing ability, sarcopenia and polypharmacy. Additional, less reliable and applicable indicators included: always opened lips and non-amnestic mild cognitive impairment, especially in men. The delayed pharyngeal response is subjectively measured when instrumental assessment is not available and the 'candy sucking test' cannot be recommended because there is an inherent choking risk.

CONCLUSIONS & IMPLICATIONS

EDS difficulty in early-stage dementia can be highlighted by indicators that could be combined to create enhanced pathways to support the early identification of EDS difficulties for people living with early-stage dementia with a view to preventing complications and facilitating informed discussions regarding wishes in the event of further deterioration. Exploring the experiences of people living with dementia and their families' perspectives on potential indicators of EDS difficulty may add to the existing evidence base.

WHAT THIS PAPER ADDS

What is already known on the subject Early identification of EDS difficulty in early-stage dementia may prevent complications, but more reliable and clinically measurable indicators of EDS difficulty are needed to help develop pathways to support diagnosis. What this paper adds to existing knowledge A comprehensive range of studies related to EDS identification in early-stage dementia have been selected and reviewed. Across six included studies, the most promising indicators of EDS difficulty in early-stage dementia included delayed oral transit, poor rinsing ability, presence of sarcopenia and polypharmacy. What are the potential or actual clinical implications of this work? This study could help to develop pathways to support the early identification of EDS difficulties for people living with early-stage dementia with a view to preventing complications and facilitating informed discussions regarding wishes in the event of further deterioration.

Exploring the connection between dementia and eating, drinking and swallowing difficulty: Findings from home-based semi-structured interviews

BACKGROUND

Eating, drinking and swallowing (EDS) difficulties are important to identify early. Awareness of EDS changes starts with those living with dementia or their family carers. However, little is known about early identification from the perspective of people with dementia.

AIM

The aim of this study was to understand the experience of EDS by people living with dementia in their own home.

METHODS

Published evidence pertaining to EDS difficulties in dementia was used to inform an online semi-structured interview guide. Four people living with dementia and a third-sector Empowerment Lead were invited to become co-researchers. People living with dementia and their carers were invited to be interviewed. We enquired about their past and present experiences, and future expected changes in EDS, information needs, opinions on early problem identification, and lifestyle modifications following onset of EDS difficulty. Narrative concepts of heroes and villains in their 'stories' were identified. Responses were subjected to framework analysis informed by narrative enquiry.

RESULTS

Seven people living with dementia and five family carers were interviewed. The overarching theme was a 'missed connection' between EDS difficulty and dementia. Where EDS difficulties were identified, 'compensatory changes' and a need for 'access to information' were noted.

CONCLUSIONS

The connection between potential EDS difficulties and a dementia diagnosis may not be made, even though EDS changes were recognised by people living with dementia and their family carers. This may be explained by behaviours that mask problems or allow individuals to cope or compensate. Reduced awareness may also be due to inadequate access to information and lack of specialist services. If the connection between dementia and EDS difficulty is missed it could further delay access to support services.

WHAT THIS PAPER ADDS

What is already known on the subject The prevalence of dementia is increasing and is expected to affect 9% of the population by 2040. EDS difficulties are common in people living with dementia and predispose to poorer outcomes. Better awareness of EDS changes early in the disease process of dementia or at preclinical stages can identify individuals at risk and allow for intervention prior to advanced EDS difficulties developing. What this paper adds to existing knowledge This paper reports the perspective of people living with dementia and family carers and provides insights into experiences of EDS and the challenges faced and identifies commonalities. The connection between potential EDS difficulties and dementia is missed despite various changes reported by both people living with dementia and their family carers, who tend to make compensatory lifestyle changes without support. What are the potential or actual clinical implications of this work? Lack of awareness of the connection between potential EDS difficulties and dementia may arise due to inadequate access to information to support people living with dementia and their family carers. Access to such information is needed and the quality assurance of information from reputable sources is important to people living with dementia. There is a need for greater service user awareness of signs of EDS difficulty and how to access specialist services.

A biophysiological framework exploring factors affecting speech and swallowing in clinical populations: focus on individuals with Down syndrome

Speech and swallowing are complex sensorimotor behaviors accomplished using shared vocal tract anatomy. Efficient swallowing and accurate speech require a coordinated interplay between multiple streams of sensory feedback and skilled motor behaviors. Due to the shared anatomy, speech and swallowing are often both impacted in individuals with various neurogenic and developmental diseases, disorders, or injuries. In this review paper, we present an integrated biophysiological framework for modeling how sensory and motor changes alter functional oropharyngeal behaviors of speech and swallowing, as well as the potential downstream effects to the related areas of language and literacy. We discuss this framework with specific reference to individuals with Down syndrome (DS). Individuals with DS experience known craniofacial anomalies that impact their oropharyngeal somatosensation and skilled motor output for functional oral-pharyngeal activities such as speech and swallowing. Given the increased risk of dysphagia and "silent" aspiration in individuals with DS, it is likely somatosensory deficits are present as well. The purpose of this paper is to review the functional impact of structural and sensory alterations on skilled orofacial behaviors in DS as well as related skills in language and literacy development. We briefly discuss how the basis of this framework can be used to direct future research studies in swallowing, speech, and language and be applied to other clinical populations.

Long-Term Effectiveness of Physical Exercise-Based Swallowing Interventions for Older Adults with Dementia in a Day-Care Center

Swallowing safety is one of the top health concerns of dementia. Coughing and choking (coughing/choking) are signs of impaired swallowing safety. This study aimed to investigate the effectiveness of regular physical exercise-based swallowing intervention for reducing coughing-choking at the dementia day-care center. This was a retrospective analysis with data from medical records, including age, the clinical dementia rating (CDR), and the frequencies of coughing/choking in ten days (10-day coughing/choking). Those who complied with the exercise programs were assigned to the exercise-based group (n = 22), and those who could not comply were assigned to the non-exercised-based group (n = 7). The non-exercised-based group showed more advanced age and higher CDR than the exercise-based group (p < 0.05). The 10-day coughing/choking showed significant decreases at the 5-month and 19-month in the exercise-based group and at the 5-month in the non-exercise-based group (p < 0.05). Our findings suggested that regular physical exercise-based swallowing intervention effectively alleviated coughing/choking problems of older adults with dementia and its effectiveness was long-lasting. For those who could not comply with exercise programs, noticeably with more advanced age and dementia, the effective swallowing intervention period was short-term.

A Comprehensive Assessment Protocol for Swallowing (CAPS): Paving the Way towards Computer-Aided Dysphagia Screening

Dysphagia is one of the most common problems among older adults, which might lead to aspiration pneumonia and eventual death. It calls for a feasible, reliable, and standardized screening or assessment method to prompt rehabilitation measures and mitigate the risks of dysphagia complications. Computer-aided screening using wearable technology could be the solution to the problem but is not clinically applicable because of the heterogeneity of assessment protocols. The aim of this paper is to formulate and unify a swallowing assessment protocol, named the Comprehensive Assessment Protocol for Swallowing (CAPS), by integrating existing protocols and standards. The protocol consists of two phases: the pre-test phase and the assessment phase. The pre-testing phase involves applying different texture or thickness levels of food/liquid and determining the required bolus volume for the subsequent assessment. The assessment phase involves dry (saliva) swallowing, wet swallowing of different food/liquid consistencies, and non-swallowing (e.g., yawning, coughing, speaking, etc.). The protocol is designed to train the swallowing/non-swallowing event classification that facilitates future long-term continuous monitoring and paves the way towards continuous dysphagia screening.

The Complexity of Nutritional Problems in Persons with Dementia: Expanding a Theoretical Model

BACKGROUND

Persons with dementia are at risk of developing nutritional problems. Theoretical models on nutritional problems have been developed, but have not been evaluated with healthcare professionals.

OBJECTIVE

This study aimed to explore the comprehensiveness and applicability of a theoretical model of nutritional problems in persons with dementia for daily nursing home practice.

METHODS

A qualitative design employing a combined deductive and inductive approach was used. Healthcare professionals were eligible to participate if they 1) had expert knowledge of and experience with nutritional problems related to dementia, and 2) worked in a nursing home affiliated with an academic network covering the east and south of the Netherlands. Three focus group interviews with 20 healthcare professionals from seven professions were held. We conducted thematic analysis and we compared themes with existing theoretical models from the literature.

RESULTS

We identified six themes, four of which corresponded with the existing models (observing and analysing nutritional problems; consequences of nutritional problems; functioning of the person with dementia; environmental factors). Interprofessional collaboration and ethical factors were identified as new themes. The analyses indicated interactions within each theme, between themes, and a bidirectional connection between themes.

CONCLUSIONS

This study demonstrated the relevance of interprofessional collaboration and ethical considerations in nutritional problems related to dementia. It uncovered complex bidirectional relations within and between factors regarding nutritional problems. All aspects should be taken into account to minimize the consequences of nutritional problems for persons with dementia.

A Biopsychosocial Model of Mealtime Management in Persons with Dementia, an Asset-Based Approach to Patient-Centered Care

Considering the rapid increase in the population over the age of 65, there is increasing need to consider models of care for persons with dementia (PWD). One common deficit associated with dementia progression is difficulty with successful participation in mealtimes. Difficulty participating in mealtimes in PWD is not the result of one factor, but rather a confluence of biological, psychological, and social characteristics common in dementia. Factors leading to mealtime difficulties for PWD may include changes in cognitive status, altered sensorimotor functioning, and increased reliance on caregiver support. The complex nature of biological, psychological, and social factors leading to mealtime difficulty highlights the need for a pragmatic model that caregivers can utilize to successfully support PWD during mealtimes. Existing models of dementia and mealtime management were reviewed and collated to create a model of mealtime management that considers this complex interplay. The Biopsychosocial Model of Mealtime Management builds on past research around patient-centered care and introduces an asset-based approach to capitalize on a PWD's retained capabilities as opposed to compensating for disabilities associated with dementia. We hope this model will provide a framework for caregivers to understand what factors impact mealtime participation in PWD and provide appropriate means on intervention.

The Association between Age-Related Changes in Oral Neuromechanics and Alzheimer's Disease

The global population of 80 years and older is predicted to reach 437 million by 2050. As overall brain structure and function progressively degrades, older and younger adults show differences in sensorimotor performance and brain activity in the sensorimotor regions. Oral sensorimotor functions are an important area of focus in natural aging and Alzheimer’s Disease (AD) because oral health issues are commonly found in both elderly and AD populations. While human behavioral studies on changes in oral sensorimotor functions abound, very little is known about their neuronal correlates in normal and pathological aging.

Preclinical Dysphagia in Community Dwelling Older Adults: What Should We Look For?

Purpose Traditionally, etiology of dysphagia is thought to be related to multiple medical diagnoses including stroke, head and neck cancer, degenerative neurological conditions, and so forth. However, community dwelling older adults (CDOA) can present with dysphagia in the absence of any specific etiology. The purpose of this research was to develop a multidimensional framework to help identify those CDOA at risk for dysphagia of nonspecific etiology. Method Pertinent literature was examined to identify support for the proposed framework and to explain how the various elements support the model. Results Several factors that are not traditionally thought to be associated with dysphagia can both initiate and exacerbate symptoms of swallowing difficulties. Swallowing difficulties may be subtle and underreported. Monitoring for symptoms related to preclinical dysphagia may be helpful for early identification. Conclusions Dysphagia in CDOA is complex and multidimensional. Clinicians working with older adults will benefit from considering elements described in this multidimensional framework to better understand the etiology of swallowing deficits and improve management. Supplemental Material https://doi.org/10.23641/asha.14150078.

Temporal Associations between Caregiving Approach, Behavioral Symptoms and Observable Indicators of Aspiration in Nursing Home Residents with Dementia

OBJECTIVES

Dysphagia, or impaired swallowing, is common in nursing home (NH) residents with dementia and contributes to malnutrition and diminished quality of life. Dysphagia also commonly leads to aspiration or passage of food or fluids into the airway, which can result in aspiration pneumonia-a leading cause of death for people with dementia. Currently available interventions for dysphagia aim to modify the risk of aspiration events primarily by modifying diet and positioning to improve the safety of an individual's swallow. However other potentially modifiable contextual factors relevant to mealtime care within NH settings that may influence the occurrence of aspiration events, such as the nature of caregiving interactions or occurrence of dementia-related behavioral symptoms, have not been examined. To address this gap, we examined the temporal associations between caregiving approach and behavioral symptoms as antecedents to observable indicators of aspiration among nursing home (NH) residents with dementia.

DESIGN

Secondary analysis of coded, timed-event behavioral data from 33 video-recorded observations of mealtime interactions between NH residents with dementia and caregivers.

SETTING/PARTICIPANTS

Residents with dementia who required assistance with mealtime care (n=12) and nursing assistants (n=8) from Memory Care Units (MCU) in 2 Midwestern NHs.

RESULTS

Observable indicators of aspiration were significantly more likely to occur during or following task-centered caregiver actions than person-centered actions (12% likelihood; Yule's Q 0.89; OR 95% CI 12.70-23.75) and 15-30 seconds after a behavioral symptom (5% likelihood; Yule's Q 0.65; OR 95% CI 4.18-8.57).

CONCLUSIONS

These findings provide compelling preliminary evidence that caregiver approach may influence the occurrence of aspiration. Provided the urgent need for more approaches to mitigate the complications associated with dysphagia in people with dementia, even a moderate reduction in aspiration events may be clinically meaningful. Further, well-designed observational studies with individuals with well-characterized dysphagia are needed to better understand and characterize these relationships, their temporal structures and their impacts on other relevant outcomes such as eating performance and malnutrition.