Article Archive
November/December 2018

Oral Health and Aspiration Pneumonia
By Jennifer M. Pusins, CScD, CCC-SLP, BCS-S, IBCLC; Carly Ferguson, BS; and Ashley V. Persaud, BA, SLP-A
Today's Geriatric Medicine
Vol. 11 No. 6 P. 16

According to Logemann, "swallowing refers to the entire act of deglutition from placement of food in the mouth through the oral, pharyngeal, and esophageal stages until the material enters the stomach through the gastroesophageal junction."1 Dysphagia is defined as "difficulty moving food from the mouth to the stomach."1 Dysphagia can result in serious consequences including malnutrition, dehydration, aspiration pneumonia, and death. Approximately 1 in 25 adults will present with dysphagia each year.2

The risk of developing dysphagia-related complications such as pulmonary aspiration is increased in the geriatric population.3-6 The Agency for Health Care Policy and Research (now the Agency for Healthcare Research and Quality) has reported that approximately one-third of patients presenting with dysphagia will develop aspiration pneumonia, and approximately 60,000 individuals will die from such complications each year.7

Pneumonia is caused by an inflammation of the air sacs (alveoli) of the lungs. In older adults, most pneumonia cases are caused by aspiration, termed aspiration pneumonia, which is a function-base category of pneumonia.8 Aspiration is defined as the misdirection of oropharyngeal or gastric contents into the trachea below the level of the vocal folds. Aspiration can lead to pneumonitis, abscesses, obstruction, and pneumonia.9 Aspiration pneumonia occurs when foreign material originating from the oral cavity (consisting of food debris, saliva, biofilm, or a combination of these) enters the bronchial tree and lung alveoli.10

Aspiration pneumonia is common among older adults due to poor oral hygiene, medication side effects, and medical comorbidities leading to increased risk of dysphagia. Aspiration pneumonia causes high mortality in nursing homes, where it is the second most common infection, with a prevalence between 30% and 69.6%.11-16 It's also been reported that 30% of older patients with dysphagia develop aspiration pneumonia.17

The physiology of swallowing naturally changes with increasing age. For instance, as the elasticity of connective tissues and muscle mass begin to diminish, a reduction of strength and range of motion results in deficits in the efficiency and effectiveness of the biomechanics of swallowing.18 As age advances, the speed and ease of swallowing decreases as more time is required for oral preparation of food into a bolus, which leads to decreased timeliness of swallow function.19

These anatomical and physiological changes may accumulate over time, resulting in an increase of postswallow residue during eating as well as penetration of swallowed material within the upper airway. Furthermore, advancing age contributes to a decrease in taste, smell, and oral moisture, which can further affect swallow physiology.18 The combination of these changes in the biomechanics of swallow function makes dysphagia a key contributor to pneumonia and malnutrition in the geriatric community.

In a study conducted by Chen and colleagues, 15% of individuals who were 65 years or older and residing in an independent living facility conveyed difficulties swallowing. Of those, a majority suffered significant quality of life impairments in one or more area of the MD Anderson Dysphagia Inventory. Approximately 23% of the participants believed dysphagia to be subsequent to natural aging, and approximately 37% disagreed. Results indicated that the prevalence of dysphagia is considerably high in the population of the geriatric community. Given these findings, it's imperative for the geriatric community to be appropriately educated about dysphagia in the community.20

In a 2017 study, Huang, Chiou, and Liu found that approximately 50% of individuals residing in nursing homes experience some degree of dysphagia. They reported that the residents who present with dysphagia typically have secondary complications associated with loss of mobility and/or sensation and weakness or paralysis on a specific side of their limbs and/or mouths. These deficits can make it difficult for them to know whether they've pocketed food in the mouth and not swallowed. They also diminish the residents' ability to participate independently in daily living activities such as brushing their teeth. Lack of appropriate oral care by an older adult or a caregiver can lead to a buildup of bacteria within the oropharyngeal cavity, which may further increase the risk of aspiration pneumonia.21

Oral Care and Aspiration Pneumonia
Poor oral hygiene is common in the elderly population, further increasing the risk of aspiration pneumonia. Food debris, liquid, and saliva contaminated with bacteria due to poor oral hygiene can be aspirated and cause pneumonia.9,22 The number of decayed teeth, frequency of teeth brushing, and dependence on a caregiver for oral care are significantly associated with pneumonia. Oral and dental disease also can lead to an increase in oral bacteria levels in saliva and change the composition of salivary flora.22

Koichiro reported that the oral cavities of patients who develop aspiration pneumonia have similar characteristic mucous membranes, soft tissue, teeth, and oral function including the following23:

• Residue in oral mucous epithelium and oral dryness: Due to suppressed oral function, the secretion of mucosal resting saliva increases and mixes with the residue in the oral epithelium to form a sticky paste that adheres to the oral cavity. Impaired self-cleaning function of the oral cavity leads to reduced regeneration of the oral mucous membrane, resulting in mucus remaining on the palate and lingual coating. This bacterial flora coating the palate or lingual surface contains bacteria not typically present in the healthy mouth that raises the risk of aspiration pneumonia. The main microorganism causing aspiration pneumonia is thought to be gram-negative anaerobic bacteria that live in secreta (phlegm), epithelial residue, crusts, and saliva.

• Morphological damage to oral hard tissue (teeth): Inadequate oral care can result in multiple and simultaneous cases of dental caries and potential rotting of the tooth crown. Food residue tends to attach to decayed teeth, creating a bacterial plaque and contributing to the development of bacterial flora that cannot be removed easily. Significant halitosis is a sign that decaying matter is present in the oral cavity, and the presence of such matter leads to a grave risk of aspiration pneumonia.

• Impaired oral function: Impairments in the oral phase of swallowing may be secondary to poor mastication, which prevents the formation of a bolus, and food adheres to the surface of the teeth in its original shape; lack of awareness/sensation of food in the oral cavity; and inadequate clearance of the bolus from the oral cavity, leading to oral residue. These types of functional impairments of the oral phase can cause poor oral hygiene and, consequently, increase the risk of aspiration.

Oral care management decreases the incidence of aspiration pneumonia in the elderly population. To adequately reduce the risk of aspiration pneumonia, a patient must receive sufficient oral care, including proper cleaning. At minimum, oral care should include mechanical cleaning of the lingual surface and palate to successfully remove pathogenic bacteria. The oral cavity responds promptly to proper care, becoming moist and healthy in color, and the improved oral cavity can influence the whole body.23

Koichiro outlined aspects of oral care management, which include retaining moisture in the oral cavity and cleaning the lingual surfaces and palate.23 Retaining moisture in the oral cavity is essential to oral health and function. Moisturizing agents such as gels, creams, and liquids have been suggested. Gauze, cotton, sponge brushes, or special brushes specifically designed for mucous membranes should be used to meticulously and reliably enhance the effects of moisture retention and cleaning. The lingual surface and palate frequently accumulate microorganisms. Mechanically cleaning them can help reduce the risk of aspiration pneumonia.

Clinical Implications
Dysphagia, poor oral health, and undernutrition are significantly present in the geriatric population.24,25 Aspiration pneumonia is a major problem for the elderly population that can lead to hospitalization, costly care, and mortality. The presence of dysphagia increases with advancing age due to changes in the biomechanics of swallow function, including delayed initiation of the pharyngeal swallow and weak swallow.

A delay in initiation of the pharyngeal swallow can lead to preswallow spillage of material into the hypopharynx and the trachea before or at the onset of the pharyngeal swallow. A weak swallow frequently leads to excess residue and incomplete clearance of the bolus. This residue can remain in the hypopharynx after the swallow and may enter the airway when breathing resumes. These physiologic changes are most significant with a food bolus, suggesting that aspiration of food material is more harmful than aspiration of liquid material and more likely to result in aspiration pneumonia. Aspiration of secretions and excess oral secretions are both significantly associated with aspiration pneumonia.22

Older patients are prone to poor oral health due to increased presence of periodontal and dental disease as well as lack of adequate oral care. As dental health diminishes, there's an increase in the bacterial load in the oral cavity, and aspiration of bacteria-laden oropharyngeal material into the lungs further increases the risk of developing aspiration pneumonia. Additionally, patients who are more debilitated with multiple underlying diseases, use of multiple medications, and poor functional status are at a higher risk of aspiration pneumonia.

Variables such as being dependent for feeding and oral care are also significantly related to development of aspiration pneumonia.23 Aspiration of oropharyngeal secretions, specifically saliva, may explain the origin of anaerobic bacteria that can be cultured from aspiration pneumonia.22,23

While dysphagia is a risk factor for the development of aspiration pneumonia, dysphagia alone is not sufficient to cause pneumonia. This suggests that dysphagia and aspiration may not be critical risk factors in a person who is medically stable; has a clean, healthy oral cavity; and/or is independent for activities of daily living, especially feeding. If these conditions are not present, aspiration pneumonia may develop.

The role of dysphagia and aspiration in the development of aspiration pneumonia can be better understood by considering the interaction between bacterial colonization and patient resistance to the process. Thus, it's suggested that the development of aspiration pneumonia occurs when aspiration of pathogenic material into the lung occurs and patient resistance to infection is compromised.22

Oral care is a key intervention for reducing the risk of infection, adverse health outcomes, and fatality associated with aspiration pneumonia. Oral care interventions have been shown to decrease the incidence of pneumonia in the elderly population and improve quality of life.26-28 Although professional oral care may not be possible, an oral care routine should be established and enforced for all elderly patients.

Adherence to a prescribed oral care protocol has been shown to be a simple, cost-effective method that significantly improves oral health scores within one week for patients with oropharyngeal dysphagia. Incorporating a validated oral health assessment into the oropharyngeal dysphagia screening process may increase the efficacy of identifying patients at risk of developing aspiration pneumonia. Additionally, including an oral health assessment in the speech-language pathologist's clinical assessment of oropharyngeal dysphagia should be considered. Appropriate referrals for dental treatment and incorporation of an oral care regimen should be included into each patient's rehabilitation plan.29

— Jennifer M. Pusins, CScD, CCC-SLP, BCS-S, IBCLC, is an assistant professor and clinical supervisor at Nova Southeastern University. She's a board-certified specialist in swallowing and swallowing disorders, and her area of clinical expertise is in the assessment and management of dysphagia across the life span. She's presented at the state, national, and international levels on various topics related to dysphagia.

— Carly Ferguson, BS, is a graduate student at Nova Southeastern University in the Master of Science in Speech-Language Pathology program. She has a specific interest in dysphagia and has worked with patients with dysphagia during her clinical practicums.

— Ashley V. Persaud, BA, SLP-A, is a speech-language pathologist assistant in the Miami-Dade County school district and a student in the Master of Science in Speech-Language Pathology program at Nova Southeastern University. She received her BA in liberal studies and triple minored in psychology, sociology, and business administration at the University of Houston. She received her graduate certificate in communication sciences and disorders from Florida International University.

References
1. Logemann J. Evaluation and Treatment of Swallowing Disorders. 2nd ed. Austin, TX: Pro-Ed; 1998:1-3.

2. Bhattacharyya N. The prevalence of dysphagia among adults in the United States. Otolaryngol Head Neck Surg. 2014;151(5):765-769.

3. Altman KW, Yu GP, Schaefer SD. Consequence of dysphagia in the hospitalized patient: impact on prognosis and hospital resources. Arch Otolaryngol Head Neck Surg. 2010;136(8):784-789.

4. Marik PE. Aspiration pneumonitis and aspiration pneumonia. N Engl J Med. 2001;344(9):665-671.

5. Schmidt J, Holas M, Halvorson K, Reding M. Videofluoroscopic evidence of aspiration predicts pneumonia and death but not dehydration following stroke. Dysphagia. 1994;9(1):7-11.

6. Tracy JF, Logemann JA, Kahrilas PJ, Jacob P, Kobara M, Krugler C. Preliminary observations on the effects of age on oropharyngeal deglutition. Dysphagia. 1989;4(2):90-94.

7. ECRI Health Technology Assessment Group. Diagnosis and treatment of swallowing disorders (dysphagia) in acute-care stroke patients. Evid Rep Technol Assess (Summ). 1999;(8):1-6

8. Teramoto S, Yoshida K, Hizawa N. Update on the pathogenesis and management of pneumonia in the elderly-roles of aspiration pneumonia. Respir Investig. 2015;53(5):178-184.

9. Marik PE, Kaplan D. Aspiration pneumonia and dysphagia in the elderly. Chest. 2003;124(1):328-336.

10. Müller F. Oral hygiene reduces the mortality from aspiration pneumonia in frail elders. J Dent Res. 2015;94(3 Suppl):14S-16S.

11. Mylotte JM, Goodnough S, Naughton BJ. Pneumonia versus aspiration pneumonitis in nursing home residents: diagnosis and management. J Am Geriatr Soc. 2003;51(1):17-23.

12. Shariatzadeh MR, Huang JQ, Marrie TJ. Differences in the features of aspiration pneumonia according to site of acquisition: community or continuing care facility. J Am Geriatr Soc. 2006;54(2):296-302.

13. Nakagawa N, Saito Y, Sasaki M, Tsuda Y, Mochizuki H, Takahashi H. Comparison of clinical profile in elderly patients with nursing and healthcare-associated pneumonia, and those with community-acquired pneumonia. Geriatr Gerontol Int. 2014;14(2):362-371.

14. Nogueira R. Swallowing disorders in nursing home residents: how can the problem be explained? Clin Interv Aging. 2013;8:221-227.

15. Park Y-H, Han H-R, Oh B-M, et al. Prevalence and associated factors of dysphagia in nursing home residents. Geriatr Nurs. 2013;34(3):212-217.

16. Sarabia-Cobo CM, Pérez V, de Lorena P, et al. The incidence and prognostic implications of dysphagia in elderly patients institutionalized: a multicenter study in Spain. Appl Nurs Res. 2016;30:e6-e9.

17. Rofes L, Arreola V, Almirall J, et al. Diagnosis and management of oropharyngeal dysphagia and its nutritional and respiratory complications in the elderly. Gastroenterol Res Pract. 2011;2011:1-13.

18. Sura L, Madhavan A, Carnaby G, Crary MA. Dysphagia in the elderly: management and nutritional considerations. Clin Interv Aging. 2012;7:287-298.

19. Crary MA, Groher ME. Introduction to Adult Swallowing Disorders. Philadelphia, PA: Butterworth Heinemann; 2003.

20. Chen PH, Golub JS, Hapner ER, Johns MM 3rd. Prevalence of perceived dysphagia and quality-of-life impairment in a geriatric population. Dysphagia. 2009;24(1):1-6.

21. Huang ST, Chiou CC, Liu HY. Risk factors of aspiration pneumonia related to improper oral hygiene behavior in community dysphagia persons with nasogastric tube feeding. J Dent Sci. 2017;12(4):375-381.

22. Langmore SE, Terpenning MS, Schork A, et al. Predictors of aspiration pneumonia: how important is dysphagia? Dysphagia. 1998;13(2):69-81.

23. Koichiro U. Preventing aspiration pneumonia by oral health care. JMAJ. 2011;54(1):39-43.

24. Ortega O, Parra C, Zarcero S, Nart J, Sakwinska O, Clavé P. Oral health in older patients with oropharyngeal dysphagia. Age Ageing. 2014;43(1):132-137.

25. Poisson P, Laffond T, Campos S, Dupuis V, Bourdel-Marchasson I. Relationships between oral health, dysphagia and undernutrition in hospitalised elderly patients. Gerodontol. 2014;33(2):161-168.

26. Azarpazhooh A, Leake JL. Systematic review of the association between respiratory diseases and oral health. J Periodontol. 2006;77(9):1465-1482.

27. Yoneyama T, Yoshida M, Ohrui T, et al. Oral care reduces pneumonia in older patients in nursing homes. J Am Geriatr Soc. 2002;50(3):430-433.

28. Lam OL, McMillan AS, Li LS, McGrath C. Predictors of oral health-related quality of life in patients following stroke. J Rehabil Med. 2014;46(6):520-526.

29. Murray J, Scholten I. An oral hygiene protocol improves oral health for patients in inpatient stroke rehabilitation. Gerodontol. 2017;35(1):18-24.