CONTACT LENS COMPLIANCE
Is There a Relationship Between Care System and Compliance?
Some data suggest that lens wearers who use a certain type of care system may be more compliant.
By Sarah Guthrie, PhD; Kathy Dumbleton, PhD, MCOptom, FAAO; & Lyndon Jones, PhD, FCOptom, FAAO
Practitioners acknowledge that good contact lens hygiene is one of the most important factors in keeping lens wearers’ eyes healthy. However, despite the fact that a great deal of time and research goes into producing the best means of cleaning and disinfecting contact lenses, taking proper care of their lenses is not usually at the forefront of patients’ minds. Patient education can only help so much, with many patients still likely to ignore advice and common sense and instead follow only the most expedient routine in their busy lives.
Thus, it may be in our patients’ best interests to direct them into contact lens care products that tend to encourage compliant behavior. This thought leads us to ask the question: Are certain lens care products inherently better at generating compliant behavior compared to others?
The Centre for Contact Lens Research (CCLR) at the University of Waterloo conducted a survey (Dumbleton, Jones et al, 2013; Guthrie et al, 2014) that investigated patient compliance in association with many other factors, including lens care systems used, contact lens care practices, and frequency of eye examinations. These datasets were then analyzed to consider patient compliance as a function of lens care regimen used.
The survey was approved by a Research Ethics Committee at the University of Waterloo and was conducted following the tenets of the Declaration of Helsinki. Eyecare practitioners (ECPs) in the United States were sent letters inviting them to complete an online registration for participation. ECPs’ offices were considered eligible to take part in the survey if the ECPs had at least 1,000 contact lens-wearing patients and prescribed daily disposable contact lenses (hydrogel or silicone hydrogel) in addition to two-week and one-month replacement silicone hydrogel contact lenses.
Coded materials were mailed to eligible ECPs, who were asked to invite up to 50 patients presenting to their offices for a regular eye exam to participate in the survey. Patients were eligible to participate if they were at least 16 years old, had previously received a full eye exam in the office, and were wearing either daily disposable contact lenses (hydrogel or silicone hydrogel) or two-week or one-month replacement silicone hydrogel lenses (Dumbleton, Jones et al, 2013; Dumbleton, Richter et al, 2013; Guthrie et al, 2014).
When eligible patients visited the office for their eye exam, they were provided with an information letter. If they agreed to participate, they completed the patient portion of a two-part questionnaire, sealed it in an envelope, and returned it to their ECP. A separate questionnaire was then completed by their ECP with various details, including the interval between eye exams and the lens care regimen recommended. Both parts of the questionnaire were coded to allow for data matching during analysis.
All questionnaires were sent to an independent data reading center (Datacore Marketing LLC) for compilation. Data analysis of the entire dataset was conducted by the CCLR.
Out of the original 9,677 questionnaires from 457 offices (Dumbleton, Jones et al, 2013; Dumbleton, Richter et al, 2013; Guthrie et al, 2014), a subset of 6,739 questionnaires was used for this analysis. This included users of various multipurpose (MPS) or hydrogen peroxide (H2O2)-based lens care regimens. Those excluded from the analysis did not report their lens care system or were using daily disposable lenses. The H2O2 group was comprised of Clear Care (Alcon) users only.
The mean participant age was 37 ± 13 years (median 35 years; range 16 to 92 years), and 68% of respondents were women, similar to that of the larger dataset (Dumbleton, Jones et al, 2013; Guthrie et al, 2014). Most participants wore their contact lenses everyday (76%), and those surveyed were mainly established wearers, having a mean of 16 years of wearing contact lenses.
Frequency of Eye Exams
Most ECPs ask their contact lens patients to have an annual exam; in this survey, 98% of these participants were asked to return for eye exams every year. ECPs were asked to provide information about the date of the participants’ current eye exam as well as the date of their last eye exam. From this information, the time between eye exams in days was determined. On average, this group of participants returned for eye exams every 483 days. However, when the participants are grouped by care system, the H2O2 users returned slightly more frequently for eye exams compared to the MPS users (H2O2: 457 days versus MPS: 487 days, p<0.01).
Compliance with Brand Recommendations
While many ECPs will recommend specific brands of lens care products to their patients, it is interesting to know how many of those patients actually follow the recommendation. In the survey, ECPs were asked to provide information about which brand of contact lens care product they recommended to the participants at their previous visit. Participants were asked what product they were currently using and were shown packaging images to facilitate the correct identification. Having both pieces of information allowed us to calculate the participants’ compliance with the care solution recommendation.
Overall, participant compliance with brand recommendation was 41%. Interestingly, when their ECP recommended a H2O2-based solution, 79% of the participants reported using that recommended care system. However, when a specific MPS brand was recommended, only 34% of the participants reported following the recommendation.
It is also interesting that, regardless of whether a participant follows a recommendation, there is a lack of agreement that a recommendation was even made. For those participants whose ECPs reported making a brand recommendation, only 51% of patients responded that they had received a recommendation. Again, H2O2 users showed greater agreement with their ECPs, with 67% agreeing that they had received a recommendation, compared to 48% of MPS users. This result suggests that many patients may ignore or forget a specific MPS recommendation, but H2O2 care system recommendations are more regularly heard, remembered, and followed.
Compliance with Lens Care
Patients maintaining good practices for disinfecting and handling their lenses is one of the most important components of preventing infection in contact lens wearers. The Centers for Disease Control and Prevention (CDC) has recently drawn attention to the link between poor contact lens hygiene and eye infections/complications in contact lens wearers (CDC, 2014); the CDC subsequently reported that approximately 99% of contact lens wearers in a 2014 survey admitted to one or more risky contact lens hygiene behaviors (Cope et al, 2015). Previous reports have shown that proper cleaning and replacement of contact lens cases on schedule would reduce instances of contact lens-related microbial keratitis among lens wearers by 62% (Stapleton et al, 2012) and that reuse of solution was linked to three times the risk of infection in a Fusarium keratitis outbreak (Chang et al, 2006) and 2.8 times the risk of infection in an Acanthamoeba keratitis outbreak (Verani et al, 2009).
To ascertain how compliant the surveyed participants were with proper lens care procedures, a section of the survey was dedicated to learning about lens care and handling practices. Participants were asked a series of questions regarding hygiene, lens cleaning, and case maintenance, of which six questions were used to determine a “sum lens care compliance score.” Each question received a score of between 0 (least compliant) and 4 (most compliant) as outlined in Table 1. From the results, we determined whether H2O2 users were more or less compliant compared to MPS users. For the purposes of this comparison, questions related to rubbing and rinsing of lenses have not been included, as manufacturer instructions differ significantly between MPS and H2O2 care systems.
|Content of question||4||3||2||1||0||MPS||H2O2|
|1||Hand wash, removal||Every time||Most times||Never||2.9 ± 1.4||2.9 ± 1.4|
|2||Hand wash, application||Every time||Most times||Never||3.2 ± 1.3||3.3 ± 1.2|
|3||Top off||Never||Occasionally||Frequently||Every night||3.3 ± 1.2||3.8 ± 0.7|
|4||Clean case||Every day||Most days||Once/week||Once/month||Never||1.9 ± 1.4||1.7 ± 1.7|
|5||Store case||Caps off/down||Caps off/up||Caps on||0.8 ± 1.4||1.0 ± 1.4|
|6||Replace case||Every month||3 months||6 months||Every year||Never||2.0 ± 1.3||3.1 ± 1.1|
MPS and H2O2 users were equally likely to wash their hands for lens removal or application, and both tend to do so most of the time. Both MPS and H2O2 users were equally unlikely to store and clean their lens cases appropriately, with all patients in need of more education on that topic. H2O2 users were, however, four times less likely to “top-off” (p<0.01) their cleaning solution compared to MPS users. This helps substantiate previous assertions that H2O2 users top-off less—a conclusion drawn from their purchasing patterns of buying almost 50% more solution compared to MPS users (Brimer, 2013).
While it is recommended to replace contact lens cases anywhere from every month to every three months, in this survey 38% of participants indicated that they either never replaced their contact lens case, or they replaced it every year. Again, in this regard, H2O2 users were more compliant—seven times less likely to use their contact lens case beyond three months (p<0.01). Both of these aspects of lens care compliance related most directly to the nature of care solution employed. When using H2O2, the vigorous nature of the bubbling action is maintained most effectively with fresh solution and a frequently replaced case, reinforcing positive behavior and perhaps explaining why H2O2 users are more likely to use fresh solution and a fresh case.
When individual compliance scores were subsequently used to calculate an overall compliance score (0 to 24), H2O2 users had higher compliance scores compared to MPS users (H2O2: 15.9 versus MPS: 14.2, p<0.01) (Table 2). This supports a previous report of increased compliance among H2O2 users in which, in a survey of 80 daily wear participants, overall compliance with lens care was reported as 37% for MPS users versus 100% for H2O2 users (Dumbleton et al, 2007).
|Lens care compliance score (0 to 24)||14.2 ± 4.4||15.9 ± 4.1|
The results of this study suggest that many aspects of compliance are positively associated with use of a H2O2 lens care system, specifically Clear Care in this survey. Lens wearers who used this system returned to their ECPs for eye exams at shorter intervals compared to their MPS-using counterparts. When ECPs recommended a certain lens care brand to patients, the H2O2 users were more likely to remember the recommendation and to report using it at their next visit. The H2O2 users were also more compliant with their lens care regimen, being four times less likely to reuse care solution and seven times less likely to use their lens case beyond three months. Thus, directing patients into a H2O2 care system may well be in their best interests, and this may be one method of improving overall compliance with care solutions. CLS
This survey was funded by Alcon Research, Ltd. Editorial and financial support for this article provided by Alcon Research, Ltd.
For references, please visit www.clspectrum.com/references and click on document #245.
Dr. Guthrie is a research associate in the Centre for Contact Lens Research (CCLR) at the University of Waterloo.
Dr. Dumbleton is director of Clinical Operations for Ocular Technology Group – International. She was formerly head of Clinical Research at the CCLR and has conducted several studies on compliance with contact lens wear. She is also a consultant or advisor to Alcon and has received travel funding from Alcon and Johnson & Johnson Vision Care Inc. (JJVCI).
Dr. Jones is a professor, University Research chair, and director of the CCLR at the University of Waterloo. He is a consultant or advisor to Alcon and JJVCI and has received research funding or honoraria from Advanced Vision Research, Alcon, AlgiPharma, Allergan, CooperVision, Essilor, JJVCI, Ocular Dynamics LLC, Oculus, Ocusense, TearScience, and Visioneering Technologies.