Dryness of the Eyes and Mouth

The two often go hand in hand.

By Justin T. Kwan, OD

Why would saliva be important to eye care? In the spirit of caring for the entire patient and not just his or her eyes, we have to pay attention to the connection between the mouth and the eyes. Patients often see their dentists and their optometrists more often than they see their primary care physicians. Saliva is critically important in maintaining oral health, just like the tears are important to the ocular surface. In fact, these mucous membranes and complex environments are similar in many ways. Dehydrated surfaces in either case can lead to inflammation, which translates into discomfort and a reduction in quality of life.

XEROSTOMIA

Xerostomia, or dry mouth, is a term describing dryness of the oral cavity that results from insufficient saliva secretion or a complete lack of saliva.1 There is also a subset of patients who feel that they have a dry mouth despite normal secretory function of the salivary glands. The overall prevalence of xerostomia varies between 12% and 30%,2 on par with the prevalence of dry eye disease (DED). Many commonly prescribed drugs cause xerostomia: diuretics, antidepressants, antihistamines, neuroleptics, bronchodilators, antianxiety medications, angiotensin converting enzyme inhibitors, opioids, and others.3

Several instruments are available to assess patients for the presence of xerostomia. A 10-question structured interview developed by Fox et al elicits yes or no responses regarding mouth dryness, food consumption, saliva, and compensatory behaviors.4 Efforts have been made to shorten the official xerostomia inventory 11-item questionnaire to make it easier for patients to complete without losing diagnostic value.5 For simplicity’s sake, we took the liberty of shortening it down to one question in a survey we use in optometric clinical care. The results are discussed herein.

FINDING SJÖGREN SYNDROME IN PRACTICE

Figure 1. The Sjo diagnostic test combines three proprietary biomarkers with four traditional ones.

The diagnosis of Sjögren syndrome appears to be a moving target, as described by Bowman and Fox.6 Subjective and objective tests are often used, but the criteria for diagnosis vary among guidelines from several international rheumatology groups.

The Sjö diagnostic test (Bausch + Lomb) combines three proprietary biomarkers with four traditional ones, potentially leading to earlier diagnosis and better specificity and sensitivity (Figure 1).7

In optometric care, a simple way to screen for DED is to make updates to overhaul the health history form. The eye care provider ensures that the review of systems portion of the form is in line with Medicare, and includes examples under the sections for head and neck (dry mouth), endocrine (fatigue), and musculoskeletal (joint pain) issues. These would not be specific to autoimmune conditions, but can start a conversation.

Figure 2. The DEQ-58 questionnaire can help to elicit dry eye symptoms.

Even more important is to use a validated DED questionnaire. Chalmers et al created a short five-item questionnaire, the DEQ-5 (Figure 2).8 Use of a cutoff score of 14 or higher maximized the instrument’s sensitivity (82%) and specificity (54%) for differentiating non-Sjögren keratoconjunctivits sicca from Sjögren syndrome. These authors also reported that a score of 8 is the cutoff between controls (normal) and DED patients. The maximum score is 22.

The Ocular Surface Disease Index (OSDI) is widely used in research, the literature, and in everyday DED patient care. In a cohort of 14 patients with Sjögren syndrome, before treatment with eyelid margin debridement scaling, the mean OSDI score was 58.3 (±22.1) out of 100.9 In another report, a cohort of 49 individuals with Sjogren syndrome had a mean OSDI of 37.5 (±24.0).10 Researchers often cite scores of 13 or 15 as the cutoff between normal and DED on the OSDI. Other useful cutoffs can be higher than 30 for moderate DED and higher than 45 for severe disease.11 Lastly, the Standard Patient Evaluation of Eye Dryness or SPEED questionnaire addresses both frequency and severity for four symptoms. The cutoff between normal and dry can be either 4 or 6.12,13

Clinical examination for DED is rather simple. Lissamine green vital dye is instilled, and allowed to soak into the cornea, conjunctiva, and lid wiper for 1 minute. Waiting too long will result in less staining as the dye rinses away. The examiner must be careful to differentiate punctate and coalesced staining from pooling in the conjunctival folds.14 The Schirmer I test is performed in both eyes, with the strips left in for 5 minutes without anesthetic. Performing Schirmer testing after lissamine green will be confounded by the extra saline mixed with the lissamine green. However, performing Schirmer before lissamine green can induce more staining. Fluorescein is instilled to grade corneal staining.

Whitcher et al devised a simple, quantitative, and reproducible system called the Sicca Ocular Staining Score (OSS; Figure 3).14 Taking into account the skewed distribution of non-Sjögren keratoconjunctivitis sicca and Sjögren keratoconjunctivitis sicca scores and their median OSS of 5 and 9 respectively, an OSS of 7 or higher is highly suspicious for Sjögren. Figure 4 shows an eye with significant corneal staining and how it would be scored using the OSS.

Figure 3. The Sicca Ocular Staining Score (OSS).

Figure 4. Oculus Keratograph 5M image of an eye with significant corneal staining. On the OSS, grade 3 corneal staining + 2 extra points = a score of 5.

TREATMENT

Treatment for DED such as corticosteroids, cyclosporine (Restasis; Allergan), punctal plugs, and high-dose triglyceride omega-3 fatty acid fish oils should be considered. In addition, scleral contact lenses with or without autologous serum can be beneficial in protecting and healing the ocular surface. The rheumatologist may prescribe oral pilocarpine twice daily at the lowest dose, but this may induce unpleasant side effects such as increased sweating. A preferred newer drug is Evoxac (cevimeline HCl).

Novel, advanced therapies include electrostimulation. Allergan acquired Oculeve last year, mainly for its OD-01 noninvasive nasal neurostimulation device that increases aqueous tear production. On the oral side, the SaliPen (Saliwell) is an electrostimulation device that is placed in the mouth for 1 to 5 minutes to improve symptoms of oral dryness, oral comfort, speech capacity, swallowing capacity, and sleep quality.

A systematic review of the literature on nonpharmacologic interventions for primary Sjögren syndrome, including acupuncture and psychodynamic group therapy, found that most studies were of low quality and high risk of bias; the authors called for further study.15

ODDS ARE THAT BOTH ARE DRY

Along with colleagues Leslie O’Dell, OD, and Milton Hom, OD, I performed a study to evaluate the strength of association between DED and xerostomia. Our results were presented at last year’s American Academy of Optometry Annual Meeting.16 We asked 563 patients “How often does your mouth feel dry?” and “How often did you experience dryness?” and then the same questions in relation to eye dryness. The surprising result was that individuals with dry eyes had 3.47 times increased odds of also having dry mouth.

The worldwide collaborative effort to assemble and compose the Dry Eye Workshop II report will hopefully shed new light on DED. Preliminary subcommittee summaries will be presented at the Tear Film & Ocular Surface Society meeting in September 2016. With many pharmaceutical agents in the pipeline, it is hoped that soon eye care physicians can provide better symptomatic relief in this complex condition of DED and dry mouth that can so adversely affect patients’ quality of life. It is critically important that eye care providers take a holistic approach to therapy, manage each patient individually, and take into account the challenging environments patients must navigate. n

1. Wiener RC, Wu B, Crout R, et al. Hyposalivation and xerostomia in dentate older adults. J Am Dent Assoc. 2010;141(3):279-284.

2. Glore RJ, Spiteri-Staines K, Paleri V. A patient with dry mouth. Clin Otolaryngol. 2009;34(4):358-363.

3. Scully C. Drug effects on salivary glands: dry mouth. Oral Dis. 2003;9(4):165-176.

4. Al-Dwairi Z, Lynch E. Xerostomia in complete denture wearers: prevalence, clinical findings and impact on oral functions. Gerodontology. 2014;31(1):49-55.

5. Thomson WM, van der Putten GJ, de Baat C, et al. Shortening the xerostomia inventory. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011;112(3):322-327.

6. Bowman SJ, Fox RI. Classification criteria for Sjogren’s syndrome: nothing ever stands still! Ann Rheum Dis. 2014;73(1):1-2.

7. Shen L, Suresh L, Lindemann M, et al. Novel autoantibodies in Sjogren’s syndrome. Clin Immunol. 2012;145(3):251-255.

8. Chalmers RL, Begley CG, Caffery B. Validation of the 5-Item Dry Eye Questionnaire (DEQ-5): discrimination across self-assessed severity and aqueous tear deficient dry eye diagnoses. Cont Lens Anterior Eye. 2010;33(2):55-60.

9. Ngo W, Caffery B, Srinivasan S, et al. Effect of lid debridement-scaling in Sjogren syndrome dry eye. Optom Vis Sci. 2015;92(9):e316-320.

10. Bunya VY, Langelier N, Chen S, et al. Tear osmolarity in Sjogren syndrome. Cornea. 2013;32(7):922-927.

11. Sullivan BD, Whitmer D, Nichols KK, et al. An objective approach to dry eye disease severity. Invest Ophthalmol Vis Sci. 2010;51(12):6125-6130.

12. Asiedu K, Kyei S, Mensah SN, et al. Ocular Surface Disease Index (OSDI) versus the Standard Patient Evaluation of Eye Dryness (SPEED): a study of a nonclinical sample. Cornea. 2016;35(2):175-180.

13. Blackie CA, Solomon JD, Scaffidi RC, et al. The relationship between dry eye symptoms and lipid layer thickness. Cornea. 2009;28(7):789-794.

14. Whitcher JP, Shiboski CH, Shiboski SC, et al. A simplified quantitative method for assessing keratoconjunctivitis sicca from the Sjogren’s Syndrome International Registry. Am J Ophthalmol. 2010;149(3):405-415.

15. Hackett KL, Deane KH, Strassheim V, et al. A systematic review of non-pharmacological interventions for primary Sjogren’s syndrome. Rheumatology (Oxford). 2015;54(11):2025-2032.

16. Kwan J, O’Dell L, Hom M. Relationship between dry eye and dry mouth symptoms. American Academy of Optometry Annual Meeting; October 7-10, 2015; New Orleans, LA.

Justin T. Kwan, OD
• Assistant professor, Southern California College of Optometry, Marshall B. Ketchum University, Fullerton, California
• (714) 449-7472; jkwan@ketchum.edu
• Financial interest: none acknowledged