Did you know…
…what puts people at risk for dry eye?
Sure, we all know some of the factors, at least anecdotally. We know about Sjogrens Syndrome, and laser surgery, and computer use and contacts. And we know it's more of an older women's disease than anything else, although that sure seems to be changing.
But what if we went strictly by the numbers - the epidemiology studies?
TFOS DEWS II (a/k/a The Dry Eye Bible), published in 2017, included an extensive epidemiology report (Stapleton et al) summarizing what we've learned about dry eye epidemiology, including risk factors, in the past ten years, i.e. since the original DEWS report. By great good luck I got to go to Paris to participate in the first meeting of the wonderful team that wrote this report, headed up by Fiona Stapleton from the University of New South Wales.
I revisit this epidemiology report often, but not often enough. Every time I look at Table 3 (scroll down after clicking) I find myself re-learning something. Something that I thought was definitely in the top few, turns out to be inconclusive. Something I knew was a risk, but not one of the worst, seems higher on the list.
In fact, it’s a powerful reminder of how much science and conventional wisdom or widely held beliefs often fail to coincide.
And how easily what we know may get outdated, and how hard it is to root out outdated information.
Think flat earth.
So:
What do experts agree are the most consistent risk factors for dry eye disease?
“Consistent” here means there’s been good quality studies, it makes sense, and there’s plenty of research behind it. TFOS DEWS II makes a helpful distinction between modifiable and non modifiable - what we might call avoidable and unavoidable risks.
Non modifiable risks (i.e. you can’t help it)
Aging
Female sex
Asian race
MGD
Connective tissue diseases
Sjogren Syndrome
Modifiable risks (i.e. you might be able to help it)
Androgen deficiency
Computer use
Contact lens wear
Hormone replacement therapy
Hematopoietic stem cell transplantation
Environment: pollution, low humidity, sick building syndrome
Medications: antihistamines, antidepressants, anxiolytics, isotretinoin
Then there’s “Tier 2”… the “probable” risk factors.
What are these? Things that have come up in peer-reviewed studies but the information isn’t conclusive, or good information but that wasn’t published in peer-reviewed journals.
Again, these come in two flavors:
Non-modifiable risk factors
Diabetes
Rosacea
Viral infection
Thyroid disease
Psychiatric conditions
Pterygium
Modifiable risks
Low fatty acids intake
Refractive surgery
Allergic conjunctivitis
Medications: anticholinergics, diuretics, beta-blockers
Then there’s “Tier 3”… the “inconclusive” risk factors
Inclusive, in this context, means probably it came up a lot but some studies may have contradicted each other, or the information just plain made sense despite not being conclusive.
Non-modifiable
Hispanic ethnicity
Menopause
Acne
Sarcoidosis
Modifiable
Smoking
Alcohol
Pregnancy
Demodex infestation
Botulinum toxin injection
Medications: multivitamins, oral contraceptives
Interesting, n’est-ce pas?
Would you really expect to see multivitamins on any of these lists?
Or oral contraceptives?
Would you have expected to see menopause so far down the list? (On the other hand, androgen deficiency is at the top of the consistent list, so that’s a clear distinction.)
Did you imagine psychiatric conditions (note that section 4 specifically emphasizes depression and anxiety) would be right smack dab in the middle?
Remind me to start surveying about what people (patients and doctors) THINK the dry eye risk factors are!