Dry eyes should not be dismissed as a minor inconvenience and something quickly remedied with over-the-counter eye drops. Dry eye disease is actually an impressively complex condition that significantly affects patients' quality of life. In fact, one study found that the self-reported impact of severe dry eye disease was similar to that of dialysis. You can improve your care of patients with this disease by addressing these five common myths. Myth 1: Dry Eye Disease Is All About Dryness Dry eye seems to be a straightforward disease—a physical lack of tears resulting in discomfort that is remedied by lubricants. In reality, dry eye disease is a multifactorial condition that follows a self-perpetuating cycle in which hyperosmolarity plays a central role. Hyperosmolarity may result from increased evaporation (evaporative dry eye), decreased lacrimal section (aqueous-deficient dry eye), or a combination of both. Hyperosmolarity of the tear film triggers a variety of inflammatory reactions that ultimately lead to corneal damage and decreased tear film quality, thus perpetuating the cycle. The tear film has the greatest optical power of any ocular surface. The effects of dry eye disease are not limited to the patient's symptoms; there are ocular consequences as well. An unstable tear film that dissipates too fast negatively impacts visual acuity because the tear film has the greatest optical power of any ocular surface. Fluctuating vision that clears with blinking is characteristic of dry eye disease. Myth 2: A Feeling of Dryness Is Required for Diagnosis A common misconception is that symptoms of dryness are necessary to diagnose dry eye disease. Certainly, dryness is a frequent complaint, but patients may experience a foreign body sensation, usually bilaterally. Although itching is typically associated with allergic conjunctivitis, it is often present in patients with dry eye disease. Another counterintuitive symptom may be watery eyes. There are two major systems of tear production: basic and reflexive. When the basal rate of tear production is inadequate, the reflexive tears engage, potentially leading to an overproduction of tears and subsequent epiphora. Burning and redness are two other symptoms often associated with dry eye disease. A small amount of discharge may even be present in dry eye disease, although such discharge is typically connected with conjunctivitis. Why is there so much variation in patient symptomatology? Research seems to indicate corneal sensitivity itself may actually be altered during the disease process of dry eye. How the cornea perceives pain may change, with the cornea becoming less sensitive the longer the cycle of dry eye continues. This phenomenon may help explain the discrepancy between clinical signs and patient-reported symptoms. Myth 3: The Diagnosis of Dry Eye Disease Is Straightforward The clinical diagnosis of dry eye disease is far from simple. No one diagnostic test is considered to be all encompassing. Objective tests, with clearly established cutoffs, have been challenging to develop. To further complicate matters, some patients with pronounced clinical signs, including decreased tear breakup time, corneal staining, and increased tear osmolarity, can be entirely asymptomatic. Conversely, some patients may report severe symptoms with minimal to no clinical signs. Redness, foreign body sensation, and itching could be symptoms of dry eye disease, but they could also be symptoms of conjunctivitis. Dry eye disease must be included in the differential diagnosis for acute red eye because this chronic condition may have acute flare-ups. Conditions such as dry eye disease, blepharitis, or episcleritis that involve inflammation may have similar symptoms because the ocular surface has only a limited repertoire of responses, regardless of the insult. Myth 4: Dry Eye Disease Only Impacts Older Patients The prevalence of dry eye disease increases with age by about 8%-10% per decade, but dry eye disease is not uncommon in younger people. The risk of systemic conditions associated with dry eye disease (eg, diabetes, arthritis) also increases with age, but some factors that make dry eye disease more likely—refractive surgery, contact lens wear, and digital device use—are more common in the younger population. Dry eye disease secondary to refractive surgery is thought to have a neurotrophic component due to impact of the surgery on the corneal nerves, and it can be particularly difficult to treat. The presence of a contact lens on the eye alters the integrity of the tear film and can exacerbate dry eye symptoms. Another factor, although one not yet fully understood, is screen time. Increased time spent on digital devices typically results in a reduced blink rate, thus promoting corneal desiccation. Lash extensions, also more favored by the younger population, can cause adverse effects on the tear film, as can traditional eye cosmetics and eyelid tattooing. More dry eye studies should target people younger than 40 years to more accurately estimate the prevalence in this population. Myth 5: Everyone Needs the Same Treatment for Dry Eye There is no one-size-fits-all treatment for dry eye. Other than lubrication, several different options are available for relief of dry eye symptoms, but no one option is universally effective. Punctal plugs may be a good treatment for some types of dry eye disease but are not a viable option for every patient due to punctal anatomy and also cost. Topical steroids can help temporarily calm inflammation but may cause a sharp increase in intraocular pressure. Topical immunomodulators, such as cyclosporine (Restasis) and lifitegrast (Xiidra), address the role of the immune response in the cycle of dry eye, but these drops are not always effective and sometimes cost prohibitive. The restoration of tear film homeostasis is the goal of treatment, but progress toward this goal can be notoriously difficult to measure. The inconsistency between the severity of symptoms and signs in dry eye disease complicates the ability of clinicians to decide if the treatment is effective. For example, objective measures, such as tear osmolarity, may improve with treatment, but the patient may not experience symptomatic relief. Patients with similar clinical signs may respond to the same treatment very differently due to the subtle differences in the pathophysiology of the disease. The Evolving Nature of Dry Eye Disease "Evolving" is the best word to describe the current understanding of the pathophysiology and management of dry eye disease. The myths addressed herein are remnants of outdated theories about its etiology. A recognition of the complexities of dry eye disease and an awareness of the evolving nature of its treatment will help you better address the symptoms and concerns of your patients. Source
