Xerostomia, the subjective sensation of dry mouth, is a common problem developed by geriatric patients. In practice, xerostomia can impair swallowing, speech, and oral hygiene, and if left unchecked, symptoms such as dysphagia and dysarthria can diminish patients’ quality of life (QOL). Salivary gland hypofunction (SGH) is the objective measure of decreased saliva production, determined by sialometry. Although xerostomia and SGH can coexist, the 2 conditions are not necessarily related.1-4 For this discussion, the term xerostomia will denote dry mouth with or without a concomitant diagnosis of SGH.
Xerostomia is seen in a wide variety of patients with varied comorbidities. It is commonly associated with Sjögren syndrome and head and neck irradiation. The diagnosis and treatment of xerostomia often involves rheumatologists, dentists, otolaryngologists, and oncologists. Additionally, most of the scientific literature about this topic exists in dental journals, such as the Journal of the American Dental Association and the British Dental Journal. Rarer still are studies in the veteran population.5
Faced with increasing time pressure to treat the many chronic diseases affecting aging veterans, health care providers (HCPs) tend to deprioritize diagnosing dry mouth. To that point, saliva is often not considered in the same category as other bodily fluids. According to Mandel, “It lacks the drama of blood, the sincerity of sweat…[and] the emotional appeal of tears.”6 In reality, saliva plays a critical role in the oral-digestive tract and in swallowing. It contains the first digestive enzymes in the gastrointestinal tract and is key for maintaining homeostasis in the oral cavity.7 Decreased saliva production results in difficulties with speech and mastication as well as problems of dysphagia, esophageal dysfunction, dysgeusia, nutritional compromises, new and recurrent dental caries, candidiasis, glossitis, impaired use of dentures, halitosis, and susceptibility to mucosal injury.7,8 Problems with the production of saliva may lead to loss of QOL, such as enjoying a meal or conversing with others.4
Although xerostomia is often associated with advanced age, it is more often explained by the diseases that afflict geriatric patients and the arsenal of medications used to treat them.2,9-16 Polypharmacy, the simultaneous use of multiple drugs by a single patient for ≥ 1 conditions, is an independent risk factor for xerostomia regardless of the types of medication taken.16 From 2005 to 2011, older adults in the US significantly increased their prescription medication use and dietary supplements. More than one-third of older adults used ≥ 5 prescription medications concurrently, and two-thirds of older adults used combinations of prescribed medications, over-the-counter medications, and dietary supplements.17 Several drug classes have the capacity to induce xerostomia, such as antihypertensives, antiulcer agents, anticholinergics, and antidepressants.2,5,12 Prevalence of dry mouth also can range from 10% to 46%, and women typically are more medicated and symptomatic.2,3,9,13,14,16 Xerostomia can also lead to depression and even reduce patients’ will to live.18 Despite xerostomia’s prevalence and impact on QOL, few patients report it as their chief symptom, and few physicians attempt to treat it.19
In order to target polypharmacy as a cause of dry mouth, the objectives for this study were to evaluate (1) the prevalence of xerostomia; (2) the relationship between xerostomia and other oral conditions; and (3) the impact of polypharmacy on dry mouth in a veteran population.