Counterknowledge: Is Dry Eye a Disease or a Syndrome?

The answer:  IT IS A DISEASE!

Language is important and how we treat a medical ailment depends very much on what we call it.  Terminologies like disorders, syndromes and diseases get mixed up and misused and interchanged depending on the literature or even the medical professional you are speaking to.   Defining a condition correctly will change the attitude of the patient suffering from it and the doctor treating it.  Dry eye is one such disease that has been misrepresented as a syndrome in many arenas but let’s take a look at the definition of a disease versus a syndrome.

Syndrome:  a collection of signs and symptoms known to frequently appear together but without a known cause.  This grouping generally characterizes a disease or disease process

Disease:  a morbid entity characterized usually by at least two of these criteria:

1. Recognized etiologic agent (cause)
2. Identifiable group of signs and symptoms
3. Consistent anatomic alterations

Dry eye disease, also known as Keratoconjunctivitis Sicca, is the term used by the internationally recognized Tear Film and Ocular Surface Society (TFOS).  It has very clear and identifiable signs and symptoms, anatomical changes are both diagnostic and prognostic of the disease itself.  The cause, or etiology, of dry eye is an often debated subject but as a culmination of decades of scientific study, it is well agreed that it can be distilled into one or a combination of aqueous deficiency, lipid or oil deficiency and/or cicatricial (scarring).  It is also generally accepted that dry eye is an inflammatory disease, which is why the majority of pipeline drugs are targeting inhibition of specific inflammatory pathways.

Why is this conversation relevant?  Too often a ‘syndrome’ get’s swept under the rug or trivialized by medicine and pop culture.  We are swift to group symptoms together and call it a syndrome which may be reason enough to take this side-stepping approach.  However when a real and clearly defined condition affects over 25 million US adults and over 100 million people world wide, AND science has elicited cause and effect then it should become an imperative to give it ‘disease’ status; not to scare or induce fear, but to appropriately identify and manage the process.

The next time you meet someone that has dry eye disease (DED), don’t define that person by the disease but rather understand the impact that it has had on her/his life.  Ask them how many doctor’s have actually given it the attention it deserves.

In a survey of 100 patients at eyeLABS Center for Ocular Surface Diseases, the average number of eye physicians/doctors the patient had consulted for DED was 3 prior to seeing me.  I intend to be their last.

SideNote: The Ocular Surface is Skin – Treat it that way

Dry Eye Disease is a skin condition, not unlike many dermatological conditions.  The lid surface, meibomian glands and corneal tissue are variations of epithelium and sebaceous glands which will age, like the dermis does.  The lengths of cosmetics, creams, lotions and potions for the skin can help to preserve our skin, but what about the eye?  The science at eyeLABS is founded in ocular surface skin preservation and sustenance.  Lid Margin Debridement (click here for related article) and clinical gland expression provides a basis for the spectrum of treatment options and maintenance procedures available at our clinic.  Contact lens wearers in particular should actively seek these types of treatments out as they are more likely to develop lid related inflammatory conditions (lid wiper epitheliopathy) that directly impact the glands, cornea and therefore dry eye disease progression.

Dr. Richard Maharaj OD, FAAO

Director of Optometry,

eyeLABS Inc.

www.eyelabs.ca

twitter: @eyelabsinc

rmaharaj@eyelabs.ca