DRY EYE ANNUAL REPORT
2010 Annual Report on Dry Eye Diseases
A review of current findings and trends in dry eye frequency, diagnosis, and management strategies.
By Jason J. Nichols, OD, MPH, PhD, FAAO
|Dr. Nichols is an assistant professor of optometry and vision science at The Ohio State University College of Optometry. He has received research funding from Alcon, Ciba Vision, and Vistakon.|
Last year we initiated an annual issue of Contact Lens Spectrum completely devoted to dry eye conditions including general dry eye disease, blepharitis, and contact lens-related dry eye. Going into our second year, we are poised to better evaluate trends in dry eye diagnosis and management as well as to bring you cutting edge clinical tips for managing your patients.
Overview of Dry Eye Trends: Survey Results
In April 2010 we initiated a market survey of our readership designed to track important trends in dry eye and contact lens dry eye. The survey covers a range of topics including frequency estimates of some key dry eye conditions, methods of diagnosis, and treatments for dry eye and contact lens dry eye. In total, 506 usable respondents completed the survey, and there were a total of 8,080 non-respondents (response rate = 5.9 percent). However, it should be noted that not everyone completed every question. Many of the results were interesting and certainly relevant to your practice. The next sections detail those results with each figure representing the percentage of respondents.
Dry Eye Frequency, Severity, and Etiology (Non-Lens Wearers)
Dry eye disease is thought to be one of the most frequent conditions that eyecare practitioners manage. To better put this in perspective, we asked for your impressions on the frequency of dry eye in your practices. On average, you stated that out of every 100 non-contact lens patients that you examine, about 39 (± 31) have some form of dry eye disease (these results were similar to the 2009 report findings, with respondents last year indicating about 34 out of every 100 having some form of dry eye). This also seems to be somewhat consistent with, if not a bit higher than, population-based study results (Hikichi et al, 1995; Doughty et al, 1997; Schein et al, 1997; Caffery et al, 1998; McCarty et al, 1998; Shimmura et al, 1999; Albietz, 2000; Moss et al, 2000; Yazdani et al, 2001; Lee et al, 2002).
Relative to the severity of dry eye in your patients, you consider the vast majority to have mild (59 percent) or moderate (30 percent) dry eye, while you consider a smaller fraction to be severe (11 percent)—this is a bit higher compared to last year, when you said that only about 1 percent of your dry eye patients had severe disease. Figure 1 compares dry eye disease severity in non-lens wearers and in lens wearers who have dry eye.
Figure 1. Perceived dry eye disease severity.
As many of us know, contact lens wearers experience a heighted intensity of dry eye symptoms over the course of a day’s wear (Begley et al, 2002; Nichols et al, 2005). We asked for your impressions on this and found a similar observation for non-lens wearers. That is, most of you feel that your non-lens wearing dry eye patients experience dry eye symptoms that are most severe at the end of the day (62 percent), followed by morning (25 percent), and mid-day (13 percent). The frequent observation of intense morning symptoms may relate to the findings regarding blepharitis that will be discussed later; blepharitis is often associated with symptoms of ocular irritation in the morning. Figure 2 compares the diurnal cycle of symptoms in both non-lens wearers who have dry eye and contact lens wearers who have dry eye.
Figure 2. Time of day for most severe symptoms.
As reported in the Dry Eye Workshop (DEWS) reports, the two major classifications of dry eye disease are aqueous deficient and evaporative dry eye (Lemp et al, 2007). Aqueous deficiency refers to failure of the lacrimal or conjunctival systems to produce the aqueous portion of the tears, whereas evaporative dry eye refers to excessive water loss from an ocular surface that exhibits otherwise normal secretory function. Interestingly, there are actually very few studies that have quantitatively addressed the relative frequencies of dry eye falling into these two categories. However, our survey responses indicate that slightly more dry eye falls into the evaporative category (59 percent) as opposed to the aqueous deficient category (41 percent) (Figure 3). As a follow up to this question, we also asked you about the frequency of blepharitis in your patients, as blepharitis is the major contributor to the evaporative form of dry eye disease. Correspondingly, in your non-contact lens wearers who have dry eye disease, you felt that more than half (51 percent) have blepharitis (either anterior or posterior).
Figure 3. Perceived major classifications of dry eye in nonlens wearers and lens wearers.
Relative to making the actual dry eye diagnosis, most of you prefer to use a symptom assessment (24 percent) or tear breakup test (26 percent)—which is similar to what we reported last year and indicates that the methods of diagnosis have not changed. This corresponds well with prior research showing that most of you indeed prefer and actually use these two assessments most commonly in making your diagnosis, so the trend in dry eye diagnosis seems to be staying the same (Korb, 2000; Nichols et al, 2000).
Figure 4. Preferred method in making a diagnosis of dry eye.
Managing Dry Eye in Non-Lens Wearers
Managing dry eye disease today is a challenge as no one therapy is necessarily completely efficacious. This may be due to the multifactorial nature of dry eye. However, there is unquestionably a tremendous amount of clinical and research activity in this regard, so the future looks bright. Figure 5 shows the distribution of the various treatments you use for dry eye disease. As might be expected, the use of artificial tears in managing dry eye conditions was reported as the most frequent treatment, followed by warm compresses and lid hygiene. The survey did not ask for your rationale for these treatments, although this will be important for us to consider in the future.
Figure 5. One treatment used most frequently for dry eye.
It is surprising that other treatments (such as Restasis [Allergan], Azasite [Inspire Pharmaceuticals], or punctual occlusion) were not reported to be used with higher frequencies. However, it is important to emphasize that the treatments listed in Figure 5 are the first-line therapies used in treating dry eye. We also inquired about the dry eye treatments you use second most frequently (presumably when the first therapy used is not completely efficacious), which are displayed in Figure 6.
Contact Lens Dry Eye Frequency, Severity, Etiology, and Prognosis
Most practitioners managing contact lens patients know that dry eye is a significant problem. In fact, depending again on the definition of dry eye, studies have estimated the frequency of symptoms in contact lens wearers to range from 25 percent to 75 percent (Caffery et al, 1998; Begley et al, 2000; Begley et al, 2001; Nichols et al, 2005). Thus, we also asked questions pertaining to dry eye in contact lens wearers. For every 100 lens wearers that you examine, approximately 42 percent (± 21 percent) have dry eye— this is about the same that was reported in the 2009 Annual Dry Eye Report (45 percent). As noted in Figure 1, most contact lens dry eye patients have mild dry eye (64 percent), while about 27 percent have moderate and 9 percent have severe contact lens dry eye. We also asked about time of day, as again, prior research has indicated that symptoms may worsen over the course of a day’s wear of lenses (Begley et al, 2000; Begley et al, 2001; Nichols et al, 2005). Indeed, that is the case; as Figure 2 shows, 84 percent of you feel that your patients experience the most dryness/discomfort at the end of the day.
Figure 6. One treatment used second most frequently for dry eye.
As noted in Figure 3, most of you report that dry eye in contact lens wearers is evaporative in nature (as opposed to aqueous deficient). This is consistent with the classification of contact lens-related dry eye in the Dry Eye Workshop (DEWS) reports as falling into the evaporative category (Lemp et al, 2007). As a follow up to this question, we also asked about your perception regarding blepharitis (both anterior and posterior) in contact lens wearers who have dry eye (as again, blepharitis is the major contributor to the evaporative dry eye classification). You reported that on average, 36 percent of your contact lens wearers who have dry eye have blepharitis.
Data regarding the impact of dry eye in contact lens wearers is sparse in terms of their ultimate prognosis. A variety of potential outcomes could affect the prognosis of lens wearers who have dry eye including clinical outcomes (e.g., inflammation, meibomian gland disease) in addition to permanent discontinuation of lens wear. Practitioners in our survey estimated that 16 percent of lens wearers permanently discontinue lens wear each year due to contact lens dry eye problems.
Lastly, similar to our assessment of diagnostic techniques used in non-lens wearers, we also asked about practice diagnostic patterns associated with dry eye in contact lens wearers. Figure 7 shows the results, which indicate somewhat of a different pattern with corneal staining assessments being conducted as frequently as a symptom assessment as the preferred method of diagnosis.
Figure 7. Preferred method in making a diagnosis of contact lens dry eye.
Managing Contact Lens-Related Dry Eye
We asked you specifically about your management/treatment approaches for your patients who have lens-related dry eye (Figure 8). When asked about the “one most common treatment” you use for dry eye in your lens wearers, nearly half (49 percent) of you said that your overall preference was to refit patients into a different material. This was followed by recommending a rewetting drop (21 percent), and changing the care solution (12 percent).
Figure 8. One treatment used most frequently for contact lens dry eye.
We also asked a follow-up question as to the “second most common” treatment for dry eye in contact lens wearers (Figure 9). When asked this, the top four treatments remained the same as the “one most common treatment”—that is, rewetting/lubricating drops (23 percent), refit into a different contact lens material (22 percent), change care solution (21 percent), and increase replacement frequency (13 percent). The remaining response items remained at approximately the same frequency (which was low) and order of usage.
Figure 9. One treatment used second most frequently for contact lens dry eye.
Relative to the finding that refitting into a different lens material was the number-one preferred treatment for lens-related dry eye, we asked in a follow-up question what material characteristic you felt is most efficacious in reducing lens-related dry eye. As Figure 10 shows, you felt that refitting into a silicone hydrogel (planned replacement) was the most beneficial (45 percent of responses), followed by a daily disposable lens (37 percent of responses). The use of general low-water-content and high-watercontent materials (both non-SiHy) were reported to be used in low frequencies when working with patients who have lens-related dry eye. We also asked whether you felt that GP materials offered general comfort benefits compared to soft lenses, and an overwhelming number of you said that they do not.
Figure 10. General categories practitioners feel are efficacious when refitting into a different lens material to improve comfort.
Lastly, a good number of you reported considering the care solution as either the first or second line of therapy in managing contact lens-related dry eye. In this regard, we asked your thoughts on general preservatives most likely to be associated with discomfort (assuming the care solution was used properly). By far, most respondents felt that PHMB (biguanides) is most associated with discomfort (58 percent), followed by Aldox/Polyquad-based solutions (18 percent), and hydrogen peroxide-based care solutions (8 percent). Interestingly, 16 percent of you felt that there is no difference among care solutions in this regard (that is, they are all equally likely to be associated with discomfort).
Dry eye diseases continue to be among the most frequent conditions that we observe in clinical practice. Their management can be challenging as patients often find only palliative relief. We have much to look forward to on the horizon in this regard, as industry appears to have a strong pipeline of both prescription and over-the-counter products that can help us manage these conditions safely and effectively.
Contact lens-related dry eye also continues to be frequently observed in clinical practice, and management trends appear relatively unchanged this year compared to last. There will be new care solutions, in addition to new lens designs, that may prove beneficial over the next year in helping to further manage this problem. Likewise, we are learning more each day regarding the use of pharmaceuticals in managing contact lens dry eye, and there likely will be more activity in this area in the years to come.
I would like to thank our readership and the industry for their continued support of Contact Lens Spectrum in watching and reporting these important trends to you—we look forward to reporting back to you next year in the 3rd Annual Dry Eye Issue. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #176.