Article Date: 8/1/2010

Single-Use Lenses are the Best Modality for All of Our Patients
point TOPIC: Daily Disposable Prescribing

Single-Use Lenses are the Best Modality for All of Our Patients

BY ALAN P. SAKS, MCOPTOM, DIP. OPTOM, FCLS, FAAO

I am passionate about one-day lenses and have regarded them as the number-one choice for well over a decade. As cost has come down, it's become an even better option. One-day lenses cost less per day than a cup of store-bought cappuccino.

Healthy and Convenient

Daily disposable (DD) lenses are the most convenient modality and offer the least hassle. When I switch patients to DDs, they rarely want to go back to reusable lenses. We also have few unscheduled visits relating to one-day lenses. The occasional red eye, contact lens peripheral ulcer, or lens fragment in the eye are the only complications we've experienced in a five-practitioner practice with more than a million DD lenses supplied over a decade. Research confirms their general lack of complications (Solomon et al, 1996).

When we read journals or attend conferences, we are bombarded with issues surrounding contact lenses such as noncompliance, dirty lenses, solution-induced corneal staining, red eye, infections, solution recalls, contact lens papillary conjunctivitis, allergies, etc. Recent research shows that 76 to 92 percent of contact lens cases are contaminated (Wilcox et al, 2010). Prescribing single-use lenses eliminates storage cases and solutions and reduces many of these problems.

Some research and significant anecdotal experience and opinion supports this. Dart et al (2008) showed that DD lenses had a 1.56X relative risk of microbial keratitis (MK) compared to planned replacement, but this was brand sensitive. The good news is that loss of best-corrected vision was less than with other modalities. The implication is that MK is less severe in the otherwise infrequent cases of MK in DD wearers. Some may have been sleeping in one-day lenses and/or reusing them, skewing the results.

Stapleton et al (2008) showed that DDs even outperformed GP lenses' impeccable safety record as far as “severe” MK was concerned. But the MK rates per modality are, in my opinion, so variable among studies that they are an unreliable indicator for decision-making, and we need to consider other factors.

Save Patients From Themselves

Human beings tend to be lazy and will take shortcuts even when they carry risk. Dumbleton et al (2009) showed that reusable lens wearers were two to four times less compliant compared to DD wearers. I believe that providing convenience and improving compliance through ease of use and minimal fuss is the way to go:

• Most contact lens wearers are noncompliant with proper disinfection and with lens and case replacement. Shorter replacement frequency, i.e., one day, is less likely to be abused compared to reusable lenses.

• All one-day wearers need to remember is basic hygiene—wash hands before handling lenses or touching the eye—and to not sleep in lenses.

• All lens materials build up deposits irrespective of the polymer or ionicity. The more they are worn and reused, the more deposits, debris, and pathogens there are likely to be.

• The only modality that beats the convenience of one-day lenses is extended wear, but that increases the risk of MK by a factor of five to 20 times (again, variable among researchers).

Results Speak for Themselves

I'm convinced that in time, when all variables are considered and ideally controlled, science will prove that single-use lenses are the safest of all soft lens modalities. Until then I rely on what I see—and that is fantastic results, happy patients, and minimal complications all around. CLS

For references, please visit www.clspectrum.com/references.asp and click on document #177.


Alan Saks is a third-generation optometrist from New Zealand. He has served multiple terms as president of the Contact Lens Societies of South Africa & New Zealand and has served as examiner in Contact Lenses & Clinical Optometry. Alan writes for journals, Web sites, and industry, takes part in protocol studies and international panels, and he lectures and acts as a consultant. He is an advisory board member to Johnson & Johnson Australia and New Zealand.
counterpoint

Daily Disposables: Be Cautious About All the Hype

BY MATTHEW LAMPA, OD, FAAO

Daily disposable (DD) use in North America has remained relatively flat over the recent years (Nichols, 2010). However, the global trend in DD lens prescribing is on the rise (Morgan, 2010). The launch of at least two silicone hydrogel DDs in the world may in part be associated with this trend, although it is important that we take a step back and really consider the issues concerning daily disposable use from both practitioners' and patients' perspectives.

Financial Impact

One of the most noticeable considerations is the financial implication associated with replacing a contact lens on a daily basis. You might argue that in eliminating the cost of care products from the financial equation by wearing a DD lens, this will alleviate the added expense associated with the lenses themselves. This calculation assumes that the patient is purchasing a significant number of bottles of lens care solution each year. According to industry sources, a patient should use up to 12 bottles of care solution per year if he is using it correctly (including both rinsing and soaking). However, the average patient typically purchases only four bottles of lens care solution per year. This certainly narrows the gap in cost comparisons, though it does not close it.

Not the Most Convenient

Not needing lens care solutions is a step up in convenience compared to the care required with planned replacement soft lenses. However, with DDs the patient still must go through the hassle of applying and removing a contact lens each day. If ease of use and convenience is the desired outcome, the ultimate in this would be to recommend continuous wear. One study showed that patients indeed prefer extended wear over daily disposables mainly because of convenience (Nichols, 2000).

Are They Really Safer?

In looking at safety as it relates to DDs, you might assume that placing a new lens on the eye each day would place a patient at a lower risk of developing severe outcomes such as microbial keratitis (MK). However, a recent study that evaluated the relative risk of MK among soft lens wearers showed that there was a small but significantly increased risk of MK with DDs versus with regular planned replacement soft contact lenses (Dart, 2008).

The issue of safety with daily disposables may relate to compliance, as patients who are non-compliant are more likely to reuse their lenses. Patients who reuse DD lenses may not be cleaning, disinfecting, and storing their lenses appropriately as their eyecare practitioner may not have educated them on proper lens care when it “theoretically” is not needed.

Waste Not, Want Not

As expected, DDs are now even available in silicone hydrogel materials. While this is commendable, I ask whether we really need increased oxygen levels in a lens that is intended for daily wear and replaced after each use?

In addition, the amount of packaging associated with daily disposables is significantly more than that of planned replacement lenses and ends up as waste product that needs disposal. In an era in which green and sustainable practices are en vogue, excess waste is seen as irresponsible, particularly in the region of the country where I practice.

Look at the Big Picture

We need to take into account these benefits and detriments when selecting contact lenses and recommending a lens modality to our patients. There are some important factors that we need to consider before recommending DD lenses. DDs are important in our prescribing armamentarium and do offer some benefits, but we need to be mindful that they do not represent the end-all in our prescriptive arsenal. CLS

For references, please visit www.clspectrum.com/references.asp and click on document #177.


Dr. Lampa is an assistant professor of optometry at Pacific University in Forest Grove, Ore.

Contact Lens Spectrum, Issue: August 2010