Every year since 2008, clinicians and researchers who have dedicated their lives to helping people with swallowing disorders have celebrated National Dysphagia Awareness Month to raise awareness of this life-altering symptom of disease or ailment. Various professionals, from basic scientists to clinical providers, work tirelessly to improve understanding of dysphagia and its impact on stakeholders at all levels. This work ensures that people can safely and efficiently participate in one of our quintessential human behaviors: eating and drinking!
As I prepared for this year’s National Dysphagia Awareness Month, I reflected on the many challenging cases I was privileged to work on these last few years. This time of reflection reminds me of how those with ID receive little attention on systematic studies of healthcare and quality of life, and only a precious few studies have attended to specific disorders, such as those impacting the swallowing mechanism. Persons with ID experience significant healthcare inequalities, and despite improved life expectancy, it’s still at least 20 years lower than the general population [1]. To build awareness of the needs of those with ID and dysphagia, I aim to highlight key aspects of swallowing disorders in persons with ID. Sprinkled within this theme, I will provide some throwbacks of topics I’ve reviewed in previous years that are particularly salient to the dysphagia management needs of these individuals.
“In this population, dysphagia has rarely been investigated — Chadwick & Joliffe, 2009
Please show me the numbers!
The prevalence of conditions or diseases is fundamental to effectively providing public health care services to those in need. However, we know very little about this critical number concerning those with ID. Incidence rates in those with ID vary widely by country and individual studies. Most incidence studies do not include adults because very few public health administrations in many countries worldwide prescribe mandatory tracking of adults with disabilities. Where monitoring of adults with ID does occur, significant variations by country and sometimes by region are reported. With incidence rates ranging from 5.5 to 12.6 per every 1,000, it’s not hard to see why prevalence rates for adults with ID and dysphagia remain so elusive [2,3,4]. It has been suggested that dysphagia prevalence in adults with ID may be as high as 49% in the US [5]. It’s also reported that the prevalence of dysphagia increases with ID severity [6].
Dysphagia can also be referred to as an impairment in deglutition. It’s important to understand that impaired swallowing is a symptom of an underlying disease or disorder, which may be neurogenic, mechanical, or psychiatric in nature. Whatever the mechanism, dysphagia manifests in difficulty moving food and liquid from the mouth to the stomach.
“The prevalence of dysphagia in adults with intellectual disability is unknown”– Sheppard, 2006
What do we know, and what don’t we know...
Concerning those with ID and dysphagia, to date, I have found only one published work that defined the prevalence of dysphagia by swallowing stages (i.e., oral, pharyngeal, and esophageal) in persons with ID. A qualitative study by Hardwick [7] reported that of 142 adults with ID, 70% presented with oral stage dysphagia, 82% with pharyngeal stage dysphagia, and 55% with esophageal stage dysphagia [6]. When I compare this to the over six thousand articles that appear on the same topic for those with Parkinson’s disease, the four thousand articles for those with dementia, or the whopping eleven thousand for stroke survivors, the reality of our significant limitations to evidence-based clinical practice hits home!
Choking: While it’s no surprise that choking is said to be highly prevalent in this population, I bet you’d be a bit surprised to learn that no systematic review has ever investigated the reason. Clinically, choking events during meals or snacks may result from overstuffing, fast rate, poor attention, or difficulty coordinating the appropriate oral motor movements needed for eating safely. However, the lack of clinical research to confirm or refute this anecdotal evidence begs the question, what else could we be missing? And how can we provide predictive outcomes for those with choking risks if we don’t comprehensively understand the cause?
Aspiration pneumonia: Like choking risks, I would be remiss if I did not discuss dysphagia management for those with ID without including aspiration and aspiration pneumonia risks. Again, there is little data on the incidence and prevalence of aspiration pneumonia in those with ID. So, we must look to other demographics to determine possible risk factors for these individuals. It’s been shown that aspiration pneumonia is the second most common infection seen in the elderly living in nursing homes and has a 20% to 50% mortality rate in this patient group [8,9]. Research on aspiration pneumonia and dysphagia in elderly persons reported an increased risk of pneumonia when dysphagia was due to neurological impairment, large volume aspiration, poor baseline pulmonary health, deficits in laryngeal sensation, and impaired nutritional status [10]. Although a direct correlation has not been established between adults with ID and the aging population, it’s essential to consider these risks, as many of our individuals with ID demonstrate these characteristics and are now living into their elder years [11].
GI issues: GERD and motility disorders are commonly reported in those with ID and are directly linked to respiratory compromise [12]. If poorly controlled, GERD can result in aspiration of gastric contents, which is caustic to the lungs, causing chemical burns of the tracheobronchial tree and pulmonary tissues. Hence, refluxed stomach contents can result in a severe inflammatory reaction that can lead to acute respiratory distress, pulmonary infection, or permanent lung damage. Likewise, motility disorders related to anatomic abnormalities or physiologic dysfunction of the esophagus or other medical interventions such as GI surgeries can also lead to pneumonia development through these same processes.
Polypharmacy: The impacts of medication side-effects on feeding and swallowing are also of significant concern in persons with ID. Research in this area indicates that those with ID are prescribed more medications than the general population, with the incidence ranging between 11% and 60% [13]. Because of this, polypharmacy places those with ID at a higher risk for associated side effects and drug-on-drug interactions. Because those with ID are more likely to present with polypharmacy beginning at an early age, they are also more likely to experience drug-induced dysphagia due to changes in smooth muscles of the oropharynx and esophagus, movement disorders, xerostomia (i.e., dry mouth), depression of the central nervous system and esophageal injury [14]. A dry mouth is concerning for several reasons. First, effective chewing and swallowing depend on adequate saliva production. Likewise, changes in the oral biome due to a “drying out” of oral surfaces can easily lead to severe overgrowth of bacteria that, if aspirated, are harmful to the lungs [15]. In addition, polypharmacy may result in changes in levels of alertness, which can significantly increase the risks of choking or aspiration. Discussing the effects of polypharmacy on swallowing is vital as we manage dysphagia symptoms in those with ID across the lifespan. Because individuals with ID now live longer lives, they are susceptible to the risk factors associated with presbyphagia (i.e., normal aging changes in swallowing). Age-related swallowing changes can include changes in oral-motor skills and movement of swallowing structures that can increase the risk of choking and aspiration. Such factors further emphasize the importance of using a multidisciplinary approach to dysphagia management for adults with ID
“Adults with ID had a higher risk of death from aspiration pneumonia” – Landes, 2021
Keep peeling back the layers for a better understanding!
In summary, over the past several decades, better healthcare has improved life expectancy for persons with ID, and this group now experiences many of the same age-related health concerns observed in the general population. As such, the impact of dysphagia has implications for the health, safety, and general well-being of those with ID throughout their lives. At times, these could include problems related to feeding; other times, effective chewing is of concern; or there may be swallowing impairment related to a myriad of neurological, anatomical, pharmacological, or behavioral issues, all of which have a tremendous impact on the ability of individuals with ID to safely and pleasurably eat and drink whatever they enjoy…
The scoop of the week references
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- Heikura U, Taanila A, Olsen P, Hartikainen AL, von Wedt L, Jarvelin MR. Temporal changes in incidence and prevalence of intellectual disability between two birth cohorts in northern Finland. Am J Ment Retard 2003; 108(1): 19-31.
- Rantakallio, von Wedt L. Mental retardation and subnormality in a birth cohort of 12,000 children in northern Finland. Am J Ment Retard 1986; 90(4): 380-7.
- Katusic SK, Colligan RC, Beard CM, et al. Mental retardation in a birth cohort, 1976-1980, Rochester, Minnesota. Am J Ment Retard 1996; 100(4): 335-44.
- Chadwick DD, Jolliffe J. A descriptive investigation of dysphagia in adults with intellectual disabilities. J Intellect Disabil Res 2009; 53(1): 29-43.
- Sheppard JJ. Developmental disability and swallowing disorders in adults. In: Cichero J, Murdoch B, editors. Dysphagia: foundations, theory and practice. Chinchester: John Wiley & Sons Ltd 2006; p. 299-318.
- Hardwick KD. Clinical manifestations of dysphagia in individuals with mental retardation: an exploratory study [dissertation]. [Austin (TX)]: University of Texas at Austin; 1993.
- Zimmer JG, Bently DW, Valenti WM, Watson NM. Systemic antibiotic use in nursing homes. A quality assessment. J Am Geriatr Soc 1986; 34(10): 703-10.
- Crossley KB, Thurn JR. Nursing home-acquired pneumonia. Semin Respir Infect 1989; 4(1): 64-72.
- Marik PE, Kaplan D. Aspiration pneumonia and dysphagia in the elderly. Chest 2003; 124(1): 328-36.
- Bittles AH, Bower C, Hussain R, Glasson EJ. The four ages of Down syndrome. Eur J Public Health 2007; 17(2): 221-5.
- May ME, Kennedy CH. Health and problem behavior among people with intellectual disabilities. Behav Anal Pract 2010; 3(2): 4-12.
- Malcom A, Thumshirn MB, Camilleri M, Williams DE. Rumination Syndrome. Mayo Clin Proc 1997; 72(7): 646-52.
- Stortz JN, Lake JK, Cobigo V, Ouellette-Kuntz HM, Lunsky Y. Lessons learned from our elders: how to study polypharmacy in populations with intellectual and developmental disabilities. Intellect Dev Disabil 2014; 52(1): 60-77.
- Eady N, Courtenay K, Strydom A. Pharmacological management of behavioral and psychiatric symptoms in older adults with intellectual disability. Drugs Aging 2015; 32(2): 95-102.
