What is dry eye syndrome?
Dry eye syndrome is a common problem and is one of the most frequent reasons given for seeking eye care. Patients will complain of eye irritation, fatigue, dryness and visual problems such as blurriness. The causes of dry eye are many but the end result is a disturbance of the tear film due to either decreased tear production or excessive evaporation of tears.(1)
Symptoms of Dry Eye
- Foreign Body Sensation
- Eye fatigue
- Vision disturbance (i.e., blurriness)
These symptoms are not trivial and dry eye has a significant impact on quality of life. A recent study of over 500 people found that even after controlling for factors such as age, hypertension and diabetes, people with dry eye had significantly more problems with reading, using a computer, watching television and driving both during the day and at night.(2)
The blurriness experienced by people with dry eye when doing activities such as watching television, reading or driving is thought to be due in part to problems with the tear film between blinks. Specifically, the tear film breaks up much faster between blinks in people with dry eye compared to those without dry eye. When the tear film breaks up between blinks, the surface of the eye is exposed and dry areas can occur and lead to dry eye symptoms. In tests that measure the visual acuity between blinks, people with dry eye had a 50% reduction in the rate of visual acuity decay compared to people without dry eye indicating that visual acuity deteriorates faster in dry eye patients.(3)
When the impact on patient’s quality of life and visual acuity is taken as a whole, it is apparent why dry eye syndrome is considered a public health problem that requires effective treatment.
Dry eye in people with diabetes
People with diabetes frequently develop dry eye syndrome.(5) It is estimated that over 50% of people with type 2 diabetes have dry eye. Why is dry eye so frequently present in people with diabetes? There is accumulating evidence that diabetes causes changes that may predispose one to developing dry eye.
Poor glycemic control and duration of diabetes are correlated with the severity of dry eye.(4, 5)
Reduced tear production has been found in people with diabetes compared to those who do not have diabetes.(6)
Diabetic retinopathy is correlated with a decline in tear film function.(7)
In children with type 1 diabetes, there is reduced tear production and tear film stability compared to non-diabetic controls. In addition, 7% of children with diabetes were found to have dry eye compared to 0% of age-matched controls.(8)
It is hypothesized that peripheral neuropathy may affect the function of the lacrimal gland.
What are the treatments for dry eye?
Patients with dry eye should have their current medications evaluated for the potential to worsen dry eye symptoms (e.g., use of antihistamines or diuretics).(9)
Smoking or exposure to second-hand smoke should be avoided due to negative effects on the lipid layer of the precorneal tear film and tear proteins. Low-humidity environments and air drafts are both potential aggravators of dry eye symptoms and patients should be made aware to look for these in their working and home environments.(9) Patients are also encouraged to have humidifiers at work and home, especially during the winter months.
To help deal with dry eye symptoms related to computer use and reading, simple measures that may help include lowering their computer screen to below eye level, taking regular breaks and increasing the frequency of blinking.(9)
There is some evidence to suggest that dry eye symptoms can be improved with increased intake of polyunsaturated fatty acids such as omega-3 and omega-6.(10)
On the prevention front, increased omega-3 fatty acid intake has been associated with a decreased incidence of dry eye syndrome in women.(11)
For moderate to severe dry eye, punctal plugs can be used to slow tear drainage via the punctal orifice. By slowing tear drainage, these semi-permanent, non-absorbable plugs increase the volume of tears on the surface of the eye and lower the osmolarity of the tears.(1)
While all these treatments play a role in the treatment of dry eye, the majority of patients will use over-the-counter artificial tear eye drops as the cornerstone of treatment.
Eye drops for dry eye
Choosing an eye drop-many options, much confusion.
When a patient goes to the pharmacy to purchase eye drops, they are faced with a multitude of choices and are often overwhelmed. According to a 2008 Gallup survey, 50% of dry eye sufferers chose a redness reliever or an allergy drop. These are the wrong types of drops for dry eye and will not provide symptom relief.
Patients must be clearly educated to specifically choose drops that treat dry eye. A 2008 Gallup survey found that even after seeing a doctor and being diagnosed with dry eye, 33% of patients chose a redness reliever. These patients will continue to suffer symptoms due to improper medication choice.
Patients should be made aware that not all eye drops are equal. As a first step, they should be counseled that eye drops for relief of redness and eye drops to relieve allergy symptoms will not treat the symptoms of dry eye. They need to use tear replacement drops specifically designed to treat the symptoms of dry eye. When choosing between dry eye treatments, consideration should be given to using high-performance products that offer immediate patient comfort, offer fast symptom relief, provide extended protection and increased visual performance.
Dry eye is a very common problem in people with diabetes, with as many as 1 out of every 2 people affected. The symptoms have a significant impact on patient’s quality of life affecting everyday activities such as reading and driving.
Eye drops are one of the mainstays of therapy however, 50% of patients will choose an incorrect type of drop when they go to the pharmacy so education is key in communicating the need to choose drops specifically designed for dry eye sufferers and not redness relievers or allergy drops.
When choosing a dry eye treatment drop, patients should be directed towards a high-performance drop to provide immediate patient comfort, rapid symptom relief, extended protection for the eye and the ability to improve visual performance.
“Treating Dry Eye in People with Diabetes” Written By Dr. Marino Discepola, MD, FRSCS
Tu EY, Rheinstrom S, Chapter 4.23 Dry Eye in Yanoff and Duker Opthamology, 3rd edition, Â©2008 Mosby, An Imprint of Elsevier.
Miljanovic B et al, Impact of dry eye syndrome on vision-related quality of life, Am J Ophthalmol, 2007; 143(3): 409-15.
Walker PM et al, Visual function in normals compared to patients diagnosed with dry eye as measured by the inter-blink interval visual acuity decay (IVAD) test, presented at ARVO 2007.
Manaviat MR et al, Prevalence of dry eye syndrome and diabetic retinopathy in type 2 diabetic patients. BMC Ophthalmol. 2008;2:8-10.
Tumosa N, Eye disease and the older diabetic, Clin Geriatr Med 2008;24:515-527.
Cousen P et al, Tear production and corneal sensitivity in diabetes. Diabetes Complications. 2007;21(6):371-3.
Yu L, Tear film function in type 2 diabetic patients with retinopathy, Ophthalmologica 2008; 222(4): 284-91.
Akinci A, Dry eye syndrome in diabetic children, Eur J Ophthalmol 2007;17(6):873-8.
American Academy of Ophthalmology Cornea/External Disease Panel, Preferred Practice Patterns Committee. Dry eye syndrome. San Francisco (CA): American Academy of Ophthalmology (AAO); 2008. Accessed online http://one.aao.org/CE/PracticeGuidelines/PPP_Content.aspx?cid=127dbdce-4271-471a-b6d9-464b9d15b748 on March 4, 2010.
Creuzot C et al, Improvement of dry eye symptoms with polyunsaturated fatty acids. J Fr Ophtalmol 2006; 29(8):868-73.
Miljanovic B et al, Relation between dietary n-3 and n-6 fatty acids and clinically diagnosed dry eye syndrome in women. Am J Clin Nutr 2005; 82(4):887-93.
Torkildsen G et al, Evaluation of functional visual performance using the IVAD method with currently marketed artificial tear products, presented at ARVO 2009.