Assessment of xerostomia (dry mouth) in Sjogren's patients - a comparison between three tools

Correlation between Xerostomia index, Clinical Oral Dryness Scale, and ESSPRI with different hyposalivation tests.

Ola Hijjaw, Mohammad Alawneh, Khaled Ojjoh, Hazem Abuasbeh, Ahmad Alkilany, Nabeel Qasem, Mohammad Al-Essa, Saif Aldeen AlRyalat

Department of Internal Medicine, The University of Jordan, Department of Ophthalmology, The University of Jordan, Amman 

Background and objective: Xerostomia is a subjective measure of dry mouth, while hyposalivation is an objective measure of reduced saliva flow rate. In this study, we aim to assess the association between commonly used xerostomia scoring systems, with different hyposalivation measures among Sjogren Syndrome (SS) patients.

Methods: In a cohort of SS patients, we assessed xerostomia using Xerostomia index, clinical oral dryness scale (CODS), and the European League Against Rheumatism SS Patient-Reported Index (ESSPRI), and we assessed hyposalivation using unstimulated whole saliva flow (UWS), stimulated whole saliva flow (SWS), and stimulated parotid flow (SPF). We analyzed the association between xerostomia and hyposalivation using association tests in SPSS.

Results: We included a total of 49 patients in this study, of which 34 (68%) had primary SS, and 15 (32%) had secondary. CODS was significantly correlated with SWS (P=0.048), with a negative correlation coefficient of 0.216, and with SPF (P=0.009), with a negative correlation coefficient of 0.291. The dryness domain of ESSPRI was significantly correlated with UWS (P=0.031) with a negative correlation coefficient of 0.233.

Conclusion: CODS is the scoring system with the highest correlation with hyposalivation, particularly SWS and SPF, followed by ESSPRI dry domain, which is correlated with UWS. Xerostomia index is not correlated with hyposalivation.

Introduction

Sjogren’s syndrome (SS) is a chronic autoimmune disease affecting mainly the exocrine glands, especially the lacrimal and salivary glands. It is the second most common autoimmune rheumatic disease. Its prevalence ranges between 0.1% and 4.8% with a female to male ratio of 9:1, mostly in the age of 40–60 years. Generally, SS is classified into primary SS, which occurs alone without any other associated disease, and secondary SS, which is associated with other diseases such as rheumatoid arthritis and systemic lupus erythematosus. SS has a wide variety of presentations and can affect almost any organ, but it typically presents with dryness of eyes and mouth.

Xerostomia and hyposalivation are two concepts used in the diagnostic criteria of SS, which are distinguishable from each other. Xerostomia is a subjective measure, when the patient reports a daily feeling of dry mouth, while hyposalivation is an objective quantifiable measure of reduced saliva flow rate. 

Multiple scoring system has been developed to assess xerostomia and several tests for hyposalivation. Three scoring systems we will discuss in our study include Xerostomia index (XI), clinical oral dryness scale (CODS), and the European League Against Rheumatism SS Patient-Reported Index (ESSPRI). Other scoring systems include Profile of Fatigue and Discomfort (PROFAD) and Sicca Symptoms Inventory (SSI). The idea behind PROFAD and SSI development was that the main symptoms of patients with SS are dryness, pain, somatic, and mental fatigue, so these scores were developed to assess these symptoms – PROFAD for fatigue and discomfort and SSI for evaluation of dryness features.

On the other hand, hyposalivation can be assessed either without saliva stimulation (unstimulated whole saliva flow [UWS]) or with saliva stimulation (stimulated whole saliva flow [SWS] and stimulated parotid flow [SPF]), each of which has its own characteristic features. For instance, stimulated flow is less subjected to variation more than unstimulated tests, while stimulated tests are sometimes difficult to obtain. Although the main concern for clinical practitioners is xerostomia rather than hyposalivation, previous studies stressed on the strong relationship between hyposalivation and general health. In this study, we aim to find the association of commonly used xerostomia assessment scores, including XI, CODS, and ESSPRI, with different hyposalivation tests.

Methods

This study’s data were obtained from the randomized controlled trials that studied the effect of sialendoscopy on salivary gland function in patients with SS, registered at the US National Institutes of Health (ClinicalTrials.gov; number: NCT02112019).

Participants

This study included patients aged 18–75 years who were diagnosed with SS based on the 2002 American–European Consensus Group classification criteria. 

Variables studied

Upon enrolment, each patient provided his/her demographic data regarding age and gender, and underwent the following tests to assess hyposalivation:

1. UWS: patients were instructed to start collecting saliva immediately after an initial swallow, and subsequently expectorate into a pre-weighed container every 30 seconds for a 5-minute period.
2. SWS: patients were asked to chew a 5×5 cm sheet of paraffin (Parafilm M, Pechiney, Chicago, IL, USA) and expectorate into a pre-weighed container every 30 seconds during a 5-minute period.
3. SPF: collected in plastic tubes from each parotid gland using modified Lashley cups. Stimulation with citric acid (2% w/v) was applied with a cotton wool swab to the lateral border of the tongue at 30-second intervals.
Patients were instructed to refrain from eating/chewing, drinking, brushing teeth, and smoking for 90 minutes prior to these tests.
Also the following questionnaires were used to assess xerostomia:
1. Xerostomia inventory: an 11-item score with responses from “Never” to “Always” in a Likert scale. A high total score indicates extremely dry mouth.
2. Clinical Oral Dryness Scale: a 10-point clinical scale, with a score of 1 assigned to each item. A high total score indicates increased xerostomia severity.
3. European League Against Rheumatism SS Patient-Reported Index: a 10-point scale for each of oral dryness, pain, and fatigue domains. As we are comparing xerostomia assessment questionnaires, only dryness domain was included. A high total dryness domain score indicates increased xerostomia severity.
4. Conclusion
   This study provided a comparison between three tools used in the assessment of xerostomia in SS patients. The newly developed CODS is associated with stimulated salivary flow tests (ie, SWS and SPF). XI is not correlated with any objective hyposalivation tests. Finally, ESSPRI dryness domain is associated with the UWS. This is the first study to compare the three tools together, which will guide prospective researchers in choosing the best tool according to their study aim.
5. SOURCE
6. MORE INFORMATION ON SJOGREN'S SYNDROME:
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