What are the oral implications of polypharmacy in the elderly?

This summary is based on the article published in Dental Clinics of North America: Oral Implications of Polypharmacy in the Elderly (October 2014)

Mabi L. Singh, DMD, MS; Athena Papas, DMD, PhD

 

 

 

Context

• There are age-related changes in the systems of the body, which alter the pharmacokinetics and pharmacodynamics of medications and make the elderly more vulnerable to adverse events.
• A major side effects of medications is the qualitative and quantitative change the cause in saliva (salivary hypofunction), by their anticholinergic effects.
• With salivary hypofunction, a plethora of complications arise, resulting in decreased quality of life in the elderly.

Key Points

• The elderly population is increasing and has the highest number of users of prescription and over-the-counter (OTC) medication.
• Age-related changes occur in the body, which affect pharmacokinetics and pharmacodynamics.
• Prescription and OTC medications can cause myriad side effects in the oral cavity, and the elderly are more vulnerable.
• The adverse events in the oral cavity may cause discomfort and loss of function and decrease quality of life in the elderly.

Age-Related Effects on the Body

• With advancing age, the functional abilities of organ systems tend to decrease.
• Age-related changes result in a diminished ability to distribute, metabolize, and excrete (clear) certain drugs.
• The liver is affected in several ways; there is a decrease in hepatic mass, hepatic blood flow, and enzymatic efficiency.
• The kidneys undergo age-related alterations: a decrease in renal plasma flow, glomerular filtration rate, and tubular secretion.
• There is an increased sensitivity to medications, which can result in medication-induced hepatotoxicity and nephrotoxicity.
• In the cardiovascular system: the elasticity of blood vessels begins to decrease with age. This stiffening of blood vessels results in the decreased mechanical effectiveness of the heart.
• The gastrointestinal system: the secretion of hydrochloric acid and pepsin decreases with the aging of the body, leading to changes in absorption in the gastrointestinal tract.¹
• Salivary glands: the aging process may cause the number of acinar cells to be reduced and to be replaced by fibrous and fatty tissue, causing the composition of saliva to change.^2-4

Adverse Events of Salivary Hypofunction in the Oral Cavity

• Xerostomia
• Dental carious lesions
• Candidiasis
• Burning Tongue
• Tooth Surface Loss
• Fissuring of the Tongue
• Difficulty with Swallowing and Speech
• Mucositis
• Loss of Taste Perception

Overcoming Anticholinergic Effects

• As competitive antagonists, the effect of anticholinergic drugs can be overcome by increasing the concentration of acetylcholine in muscarinic M3 receptors and increase production of saliva from the salivary glands.

Mechanical and gustatory stimulation

Chewing sugar-free gum over a prolonged period results in a functional increase in salivary flow, as well as in increases in pH and buffer capacity which can help reduce plaque acidogenicity.⁵

Xylitol

• The effects of xylitol-incorporated lozenges, spray, and gum stimulate and increase saliva, by osmotically drawing water from the tissues, improving pH, and buffering capacity of the saliva in the oral cavity.^{6, 7}
• Xylitol containing agents aid with the clearance of carbohydrate substrate, dead tissue, and microorganisms, thus reducing the rate of demineralization and inducing remineralization⁸ of the hard tissue and helping to maintain homeostasis of the soft tissue.

Supersaturated calcium and phosphate

• The use of remineralizing solutions in concentrated doses can help provide the physiologic supersaturated level of calcium phosphate that is necessary for remineralization and mucosal healing, which may enhance remineralization and decrease demineralization of the calcified tissue in oral cavity.^{9, 10}

Fluoride

• Various salts of fluoride are bactericidal and help with the reuptake of calcium and phosphate from the supersaturated saliva and the formation of fluoroapatite crystals, which are more resistant to acidic attacks.
• Prescription-strength fluoride in the form of toothpastes, gels, and professionally applied varnishes is necessary to prevent caries in a population with salivary hypofunction.

Salivary substitutes

• The evidence for caries protection from salivary substitutes is not sufficient for artificial saliva substitutes. The soothing effect of these substitutes is only temporary and must be administered frequently.
• Thus, the use of mouth rinses, sprays, and gels is inconvenient and often interruptive of daily activities. 

Regular dental care

• The frequency of dental office visits for xerostomic elderly patients should be every 3 months, when the oral cavity should be examined for any development of new dental carious lesions, soft tissue changes to assess any infection or inflammation, review of oral hygiene products, usage of prescriptions, prophylaxis, and most importantly, compliance to the regimen advised to reduce complications in the oral cavity caused by medications.

References

1. A. Mangoni, S.H. Jackson. Age-related changes in pharmacokinetics and pharmacodynamics: basic principles and practical applications. Br J Clin Pharmacol, 57 (1) (2004), pp. 6–14.
2. Vered, A. Buchner, P. Boldon, et al. Age-related histomorphometric changes in labial salivary glands with special reference to the acinar component. Exp Gerontol, 35 (8) (2000), pp. 1075–1084.
3. J. Baum. Evaluation of stimulated parotid saliva flow rate in different age groups. J Dent Res, 60 (1981), pp. 1292–1296.
4. M. Nagler, O. Hershkovich. Age-related changes in unstimulated salivary function and composition and its relations to medications and oral sensorial complaints. Aging Clin Exp Res, 17 (5) (2005), pp. 358–366.
5. W. Dodds, S.C. Hsieh, D.A. Johnson. The effect of increased mastication by daily gum-chewing on salivary gland output and dental plaque acidogenicity. J Dent Res, 70 (12) (1991), pp. 1474–1478.
6. Ribelles Llop, F. Guinot Jimeno, R. Mayné Acién, et al. Effects of xylitol chewing gum on salivary flow rate, pH, buffering capacity and presence of Streptococcus mutans in saliva. Eur J Paediatr Dent, 11 (1) (2010), pp. 9–14.
7. Aguirre-Zero, D.T. Zero, H.M. Proskin. Effect of chewing xylitol chewing gum on salivary flow rate and the acidogenic potential of dental plaque. Caries Res, 27 (1993), pp. 55–59.
8. Miake, Y. Saeki, M. Takahashi, et al. Remineralization effects of xylitol on demineralized enamel. J Electron Microsc (Tokyo), 52 (5) (2003), pp. 471–476.
9. Johansen, A. Papas, W. Fong, et al. Remineralization of carious lesions in elderly patients. Gerodontics, 3 (1) (1987), pp. 47–50.
10. L. Singh, A.S. Papas. Long-term clinical observation of dental caries in salivary hypofunction patients using supersaturated calcium-phosphate remineralizing rinse. J Clin Dent, 20 (3) (2009), pp. 87–92.