Dry eye triggers versus causes

I frequently hear people saying, or posting on DryEyeTalk, "XXX caused my dry eye."

Often, a review of their history gives even a layperson like me good reason to question whether what they are so sure of is actually correct. And even in some apparently black-and-white situations where dry eye symptoms are sudden and severe - commencing immediately after or during some identifiable event - reliably establishing cause and effect is not always that simple.

My personal belief (theory, I guess) is that in many cases, there are one or more underlying conditions - perhaps mild blepharitis/MGD, perhaps ocular allergies or rosacea, perhaps something else - but with no symptoms. Then, along comes a single traumatic event of some kind and punts you right over the edge into a fullflown severe dry eye episode. So as reasonable as it seems to blame the event that "started" it all... I think we're looking at the difference between a trigger and a cause.

Not that there's any simple straightforward line to be drawn between triggers and causes, of course. LASIK is both. And so are many of the things you'll see on the classic "Causes of dry eye" lists... surgeries, drugs, environmental factors and so on. But the point is that your "tipping point" is not necessary the beginning and the end of your dry eye story.

I was reminded of this today while speaking with a gentleman who traces his dry eye to paint exposure. From the story, it seemed compelling: No history of dry eye whatsoever, and almost immediately after a brief exposure to paint in the air he began having severe symptoms. And here he is four years later, still with dry eye (and incidentally unusually sensitive to paint). But while we were talking I happened to mention instances I know of where dry eye was attributable to mold attacking the meibomian glands. It turns out that this gentleman had had problems with mold in the house. Was that related? I have no idea. But could it be? Possibly.

Then of course there's all the people who have a drying drug or surgery... BUT did they already have bleph, rosacea, lagophthalmos, etc. beforehand?

So for those of you whose doctors seem skeptical of your claims, please don't forget that there could be a decent reason for their skepticism. Unfortunately, dry eye patients have a rough time because of the lack of validation of the life impact of their symptoms. As a result there is a tendency to take things personally and even to lump a doctor's resistance to one's claims about causation in that same "He/she does not get it!" category. Step back and put yourself in their shoes. Dry eye is a complex, usually multifactorial disease and sorting out causes can take some serious detective work.

On the other hand, if you're doing your best to be a good open-minded compliant patient and your doctor is simply not up to the task - is not willing to be a detective in the cause of helping you get some relief - don't waste your time. Move on.