Xerostomia due to systemic disease: A review of 20 conditions and mechanisms

Abstract

Xerostomia is a common complaint of nearly half of the elderly population and about one-fifth of younger adults. It causes several signs and symptoms, and compromise oral functions and health-related quality-of-life. Multiple reasons are proposed to describe the etiology of xerostomia such as local factors, psychogenic factors, and systemic diseases. In order to manage xerostomia effectively, identification of the main causality is mandatory. The aim of this review was to present systemic diseases leading to xerostomia with their mechanisms of action. We used various general search engines and specialized databases such as Google, Google Scholar, Yahoo, PubMed, PubMed Central, MedLine Plus, Medknow, EBSCO, ScienceDirect, Scopus, WebMD, EMBASE, and authorized textbooks to find relevant topics by means of Medical Subject Headings keywords such as “xerostomia,” “hyposalivations,” “mouth dryness,” “disease,” and “systemic.” We appraised 97 English-language articles published over the last 40 years in both medical and dental journals including reviews, meta-analysis, original papers, and case reports. Upon compilation of relevant data, it was concluded that autoimmune diseases most frequently involve salivary glands and cause xerostomia followed by diabetes mellitus, renal failure, and graft-versus-host disease. Moreover, the underlying mechanisms of systemic disease-related xerostomia are: autoimmunity, infiltration of immunocompetent cells, granuloma formation, fibrosis and dehydration, deposition of proteinaceous substances, bacterial infection, and side-effects of medications.

Salivary Flow Rate, Oral Yeast Colonization and Dental Status in Institutionalized and Non-Institutionalized Elderly

“…Th e DMFT index of 24.08 among institutionalized elderly (Table 3) was lower than 26.6 found among institutionalized elderly in Canada 35 and 30.75 found in Slovenia 39 . Our fi ndings may also be related to the low salivary fl ow rate, as well as poor oral hygiene 11,18 .…”

“…At such fl ow rates, oral microbial profi le includes increased numbers of microorganisms which may lead to an increased risk of oral fungal infection and high caries activity 15 . Th is is due to the role of saliva in inhibiting oral microbial colonization 11,15 . Th e mouth is a reservoir of yeasts and these fungi can be frequently isolated without related pathologic changes to the epithelium 29 .…”

“…Low salivary fl ow rate or hyposalivation is known to induce various problems including dental caries, periodontitis, denture problems, candidiasis, and mastication and swallowing problems 11,21 . Th e incidence of hyposalivation among the elderly ranges from 10% to 50% 25 .…”

“…Th ese results are consistent with the results of an investigation conducted among nursinghome residents in Holland, which found low salivary fl ow rates in 72% of the institutionalized elderly 26 . Salivary gland hypofunction may be correlated with various systemic disorders, medications, as well as the number of medications 3,11,27,28 . Th e higher incidence of decreased salivary fl ow rate which we found in the group of institutionalized elderly could be the result of a rather high number of diff erent medications or intake of medications with specifi c xerostomic side effects 27,28 .…”

“…Th e eff ect of aging on salivary fl ow is still unclear, and it seems that it is mainly the unstimulated salivary fl ow rate that is aff ected 10 . However, unstimulated salivary fl ow rate decreases with an increase in the number of medications, in particular following the intake of antihypertensive agents, tranquillizers, sedatives, hypnotics or antipsychotic agents 11,12 . Most of the elderly take at least one medication that adversely aff ects salivary gland secretion and many of these medications reduce salivary fl ow rate 3,13,14 .…”