A Review of Contact Lens Dropout

Abstract

Purpose
Contact lens (CL) dropout is likely a major factor contributing to the near stagnant growth in the CL market. The purpose of this review is to summarize the current state of knowledge related to the frequency of CL dropout and the factors associated with it.

Methods
PubMed.gov was searched on or before March 22, 2020, with the terms “contact lens” with “dropout” or “cessation” or “disruption” or “discomfort”. Pertinent articles were collected. The references from these articles were likewise searched to identify additional relevant articles. Only manuscripts written in English were included. No study design or date exclusions were imposed on this review.

Results
This literature review found that CL dropout was frequent across developed countries, with a CL dropout frequency that ranged between 12.0% and 27.4% (pooled mean = 21.7%). The top cited reason for CL dropout in established CL wearers was discomfort, while vision was the top reason in neophyte CL wearers. If given the chance, CL dropouts are often able to successfully resume CL wear up to 74% of the time. While the literature is mixed with regard to factors promoting CL dropout, meibomian gland dysfunction appears to promote CL dropout.

Conclusion
CL dropout is a frequently encountered condition that may be curtailed by early detection, patient education, alterative CL options, or early treatment of underlying ocular surface diseases such as meibomian gland dysfunction.

Full text

REVIEW
A Review of Contact Lens Dropout
This article was published in the following Dove Press journal:
Clinical Optometry
Andrew D Pucker
1
Anna A Tichenor
2
1
School of Optometry, University of
Alabama at Birmingham, Birmingham, AL,
USA;
2
School of Optometry, Indiana
University, Bloomington, IN, USA
Purpose: Contact lens (CL) dropout is likely a major factor contributing to the near stagnant
growth in the CL market. The purpose of this review is to summarize the current state of
knowledge related to the frequency of CL dropout and the factors associated with it.
Methods: PubMed.gov was searched on or before March 22, 2020, with the terms “contact
lens”with “dropout”or “cessation”or “disruption”or “discomfort”. Pertinent articles were
collected. The references from these articles were likewise searched to identify additional
relevant articles. Only manuscripts written in English were included. No study design or date
exclusions were imposed on this review.
Results: This literature review found that CL dropout was frequent across developed
countries, with a CL dropout frequency that ranged between 12.0% and 27.4% (pooled
mean = 21.7%). The top cited reason for CL dropout in established CL wearers was
discomfort, while vision was the top reason in neophyte CL wearers. If given the chance,
CL dropouts are often able to successfully resume CL wear up to 74% of the time. While the
literature is mixed with regard to factors promoting CL dropout, meibomian gland dysfunc-
tion appears to promote CL dropout.
Conclusion: CL dropout is a frequently encountered condition that may be curtailed by
early detection, patient education, alterative CL options, or early treatment of underlying
ocular surface diseases such as meibomian gland dysfunction.
Keywords: contact lens dropout, contact lens cessation, contact lens dry eye, ocular surface
Introduction
Successful contact lens wear has been defined as being able to comfortably wear
one’s contact lenses for at least 12 hours per day for at least six days per week while
still being able to see at least as well as while wearing spectacles.
1
Contact lenses
have a number of benefits for both children and adults, which include improving
one’s overall visual satisfaction, ability to play sports, and one’s overall self-
perception.
2,3
Mounting evidence also suggests that two contact lens-based options,
soft multi-focal and overnight orthokeratology contact lenses are able to slow
a child’s myopic progression,
4,6
which is potentially a major public health victory
since reducing one’s overall amount of myopia may improve one’s overall visual
experience, and it might reduce one’s chances of developing vision threatening
conditions later in life.
7
Thus, ensuring that patients are successful contact lens
wearers is now more important than ever.
Unfortunately, a large percent of contact lens wearers each year cease wearing
their contact lenses on a regular basis and many even permanently stop wearing
their contact lenses because of various reasons, which include discomfort, vision,
cost, and convenience.
8
The cessation of contact lens use is also commonly referred
to in the literature as contact lens dropout.
9
Contact lens dropout has historically
Correspondence: Andrew D Pucker
School of Optometry, University of
Alabama at Birmingham, 1716 University
Blvd, Birmingham, AL 35233, USA
Tel +1 920 579-2900
Email apucker@uab.edu
Clinical Optometry Dovepress
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plagued market growth, especially since the inception of
daily wear, reusable contact lenses.
8,10
Likewise, the intro-
duction of better contact lens designs and materials have
failed to curb contact lens dropout rates across the
world.
11,12
Since contact lens dropout is a worldwide
issue,
11,12
fully understanding its frequency and associated
factors is imperative to devising strategies for moving past
the pitfalls of modern contact lenses. Therefore, the pur-
pose of this review is to summarize the current state of
knowledge related to contact lens dropout and its asso-
ciated factors, so better contact lens designs, materials, and
fitting/management strategies can be employed to keep
patients in contact lenses longer each day and for more
years. This will subsequently allow practitioners to better
meet the refractive and health needs of their patients.
Methods
The aim of this review was to gain a better understanding of
the frequency of contact lens dropout (cessation of contact
lenses) and factors associated with it. A PubMed.gov search
was conducted on or before March 22, 2020 by entering the
term “contact lens”with “dropout”or “cessation”or “disrup-
tion”or “discomfort”. All recovered abstracts were reviewed
by the authors (ADP and AAT), and the text of articles of
interest were analyzed to determine if the studies aligned
with this review. Additional texts were recovered by search-
ing the references of the recovered manuscripts. This review
had no restrictions on study designs or dates. Only manu-
scripts published in English were included. Special attention
was given to publication date when describing the frequency
of contact lens dropout, so the readers could keep the avail-
able materials in mind when considering the frequency of
contact lens dropout.
Results
Frequency of Contact Lens Dropout
Several key factors related to the frequency of contact lens
dropout have been explored in the literature since the intro-
duction of reusable soft contact lenses. The following section
will explore these topics by first discussing the frequency of
contact lens dropout in early reusable hydrogel soft contact
lenses. It will next describe how there has been a lack of
change in the frequency of contact lens dropout with the
introduction of silicone hydrogel contact lenses. This section
will then conclude with a description of key differences
related to contact lens dropout in neophytes (new) or estab-
lished contact lens wearers. Information related to rigid
contact lens wearers will be included where appropriate,
though limited information related to this contact lens mod-
ality was detected during this review likely because there are
far fewer rigid contact lens wearers in the current market.
13
Early Soft Contact Lenses (1999 and Before)
Modern, reusable, soft contact lenses were introduced back
in the late 1980s,
8
and daily disposable soft contact lenses
were introduced into the market in 1994.
14
While these wear
modalities have somewhat simplified the contact lens wear-
ing experience, not all wearers have been able to achieve
complete contact lens satisfaction. This is highlighted by an
early, commonly cited meeting abstract by Weed et al (1993)
who surveyed established contact lens wearers in Ontario,
Canada to determine the frequency of contact lens dropout.
15
This university-based survey received responses from 568
subjects, and found that a staggering percentage (51%) of the
subjects had a past history of contact lens dropout and that of
these subjects only 48% of them tried to return to contact
lenses; the primary reason for returning to contact lenses was
because of cosmetic purposes.
15
This study furthermore
found that if a subject dropped out of contact lenses, they
typically did so within the first 2 years of contact lens wear.
15
The authors lastly found that the top two reasons for contact
lens dropout were ocular discomfort and irritation.
15
Briggs
(1996) later performed a survey of 200 self-reported contact
lens dropouts from Saudi Arabia who dropped out of contact
lenses within the past 10 years, and the authors likewise
found that the top reason for contact lens dropout was ocular
discomfort (61.0%).
12
This reason was followed by incon-
venience (30.5%), poor vision (5.5%), cost (2.0%), and
refractive surgery (1.0%).
12
Pritchard et al (1999) later published their seminal
survey on soft and rigid contact lens dropouts.
8
This
Canadian-based study received 1444 completed surveys
from subjects who completed 5 ± 6 years of contact lens
wear and found that 34% of the surveyed subjects had
ceased contact lens wear at least once during that time
period.
8
While some of these subjects returned to contact
lenses at a later date, this survey found that 12% of subject
permanently dropped out of contact lenses.
8
Pritchard et al
like Weed et al and Briggs found that the top reason for
contact lens dropout was ocular discomfort (49%).
8,12,15
In
fact, ocular discomfort was nearly equal to all of the other
reasons for dropping out of contact lenses combined:
experienced dry eye (9%), needed to replace lenses (6%),
lens cleaning too much bother (5%), experienced red eye
(5%), poor vision (4%), advised to do so by eyecare
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provider (4%), insertion/removal too much bother (3%),
pregnancy (3%), and near vision problems (3%).
8
Pritchard et al interestingly found that the contact lens
dropouts wore their contact lenses fewer days per week
than subjects who did not dropout of contact lenses.
8
This
result has since been confirmed by Pucker et al who found
that contact lens dropouts were significantly more likely to
wear their contact lenses fewer days per week and fewer
hours per day than successful contact lens wearers.
9
These
results further support comfort being an issue for many
wearers. Lastly, Pritchard et al found that subjects who
resumed contact lens wear primarily did so for cosmetic
reasons (23%) and because the discomfort/irritation symp-
toms that they were experiencing had resolved (23%).
8
Thus, the overall data from early reusables soft contact
studies suggest a permanent dropout rate between 12% and
27% (Table 1).
Modern Soft Contact Lenses (After 1999)
With the introduction of silicone hydrogel contact lenses
into the market, there were high hopes related to improved
ocular health, comfort, and overall contact lens success,
10
yet multiple studies have failed to provide support for
silicone hydrogel contact lenses yielding higher contact
lens retention rates. Richdale et al (2007) were among
the first groups to analyze contact lens dropout in
a sample that contained silicone hydrogel contact lens
wearers (hydrogel, silicone hydrogel, and rigid contact
lens wearers) in the United States.
16
The authors accom-
plished this task by surveying 730 subjects who were
between the ages of 18 and 88 years.
16
Of the subjects
who completed the survey 62.0% of them had a history of
wearing contact lenses, and 75.9% of these subjects were
still wearing contact lenses (frequency of dropout =
24.1%).
16
Subjects in this study who dropped out of con-
tact lenses again reported (multiple responses allowed)
that their top reason for dropping out of contact lenses
was ocular symptoms (64%). The following specific symp-
toms were noted by the subjects: discomfort (69%), dry-
ness (59%), grittiness (37%), itchiness (21%), photophobia
(21%), soreness (24%), and pain (21%).
16
Subjects addi-
tionally indicated that they dropped out of contact lenses
because of preference for other refractive error correction
Table 1 Summary of the Frequency of Contact Lens Dropout by Study and for All Studies
Study Study Design Neophyte/
Established
Wearer
Number of
Subjects (n)
Dropout Frequency Top Dropout Reason
Weed et al 1993
15
Canadian/Survey Established 568 26.5% Ocular Discomfort
Briggs 1996
12
~ Saudi Arabia/Survey Established 200 N/A Ocular Discomfort
Pritchard et al 1999
8
Canadian/Survey Established 1444 12% Ocular Discomfort
Richdale et al 2007
25
United States/Survey Established 730 24.1% Ocular Symptoms
Rumpakis 2010
11
International/Survey Unknown 372 15.9% United States
17.0% North America
31.0% Asia/Pacific Rim
30.4% Europe/Middle
East/Africa
Ocular Discomfort
Dumbleton et al 2013
10
Canadian/Survey Established 4207 23% Ocular Discomfort
Sulley et al 2017
17
United Kingdom/Retrospective Chart
Review
Neophyte 524 26% Poor Vision
Sulley et al 2018
18
United Kingdom/Prospective Cross-
Sectional Study
Neophyte 250 22.4% Poor Vision
Macedo-de-Araújo et al
2019
19
*
Portugal/
Prospective Cross-Sectional Study
Neophyte 95 27.4% Difficulty with Scleral Lens
Handling
Pooled Dropout
Frequency#
N/A N/A 8190 21.7% N/A
Notes: *Subjects in this study were scleral lens wearers while the majority of the subjects in the other included studies were soft contact lens wearers.
#
The Rumpakis
2010 percentage used in the pooled dropout frequency was the mean of the four countries since the number of subjects in this study was not described by region.
~
Briggs
1996 was excluded from the total number subjects in the pooled dropout frequency estimate because a frequency was not provided.
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(50%), contact lens cost or convenience (33%), and poor
vision (14%).
16
In a more recent and comprehensive study, Dumbleton
et al (2013) investigated the frequency and reasons for
contact lens dropout via an online survey in Canada.
10
A total of 4207 of the completed surveys were deemed
eligible for the study with the subjects ranging in age from
17 and 77 years with 64% of these subjects being
female.
10
This study found that 60% of the subjects were
current wearers while 40% of the subjects had a history of
contact lens dropouts.
10
While 62% of the contact lens
dropouts did resume contact lens wear, 23% of the sub-
jects were permanent contact lens dropouts.
10
Reasons for
returning to contact lenses included cosmetic (32%), con-
venience (21%), and being offered an alternative type of
contact lens (14%).
10
The top reasons for contact lens
dropout were discomfort (24.4%) and dryness (19.9%),
though subjects noted other factors such as ocular redness
(6.8%), cost (6.8%), and handling issues (6.3%). If sub-
jects dropped out of contact lenses, 27% of the subjects
dropped out within six months, 38% of the subjects
dropped out within six to 12 months, and 35% of the
subjects dropped out after one year.
10
Dumbleton et al’s data are supported by a related
Rumpakis (2010) study.
10,11
While the article from
Rumpakis was published in Review of Optometry (trade
journal), it is still commonly cited in the peer-reviewed
literature because it offers an international perspective on
contact lens dropout.
11
This study was a 27-country survey
(n = 372) of wearers, which found that contact lens dropout
rates were between 16% and 30% worldwide. Rumpakis
estimated that each contact lens dropout could translate to
$24,000 ($19,497 to $24,556 depending on country; US =
$21,695) worth of lost revenue to a clinical practice over
a patient’s lifetime.
11
The author like the above studies found
that the top reason for contact lens dropout was ocular
discomfort.
11
Thus, data from Rumpakis, Richdale et al,
and Dumbleton et al all suggest that the introduction of
silicone hydrogel materials has not curbed the frequency of
contact lens dropout.
10,11,16
Neophyte vs Established Wearers
Historically, the top cited reason for contact lens dropout has
been ocular discomfort, yet recent research has caused the
community to qualify this conclusion. More specifically,
investigators have attempted to analyze the frequency of
contact lens dropout in neophyte contact lens wearers. This
point is highlighted by a 2017 study by Sulley et al who
analyzed the one-year retention rates of neophyte contact
lens wearers.
17
This United Kingdom-based retrospective
chart review analyzed 524 charts from patients with
aknownfitting outcome (wearing contact lenses or not).
17
This study of predominantly soft contact lens wearers (98%)
found that 74% of the subjects were still wearing contact
lenses one year after being originally fit in lenses (26.0%
dropout rate).
17
Of the subjects who had a known dropout
date, 25.4% of subjects dropped out within one month,
46.7% dropped out within two months, and 75.0% dropped
out within six months.
17
Of the subjects with a known contact
lens dropout reason (more than one reason allowed), the top
reasons were poor vision (47%), discomfort (25%), and lack
of motivation (18%).
17
This study interestingly found that
only 29% of contact lens dropouts were offered an alternative
contact lens option, which indicates that practitioners should
more actively investigate and try to solve the problems of
contact lens wearers.
17
The above data from Dumbleton et al
likewise suggests that patients should be reminded of the
many benefits (eg, cosmetic) offered by contact lenses to
help them rekindle their motivation to wear contact lenses.
10
Sulley et al (2018) later attempted to answer the same
question in a different manner by prospectively enrolling
531 neophyte subjects (250 fully completing study) and
fitting them in appropriate soft contact lens. Retention
rates were then analyzed over one year.
18
Sulley et al’s
prospective study came to a similar conclusion to their
chart review with regards to dropout rates (22.4%), time
to contact lens discontinuation, and primary reason for
contact lens dropout.
18
Macedo-de-Araújo et al (2019) like-
wise completed a prospective study of contact lens retention
rates over a one year time period; however, Macedo-de-
Araújo et al specifically studied scleral lens wearers (large
dimeter gas permeable lenses).
19
While Macedo-de-Araújo’
et al’s prospective study found a similar contact lens drop-
out rate (27.4%) compared to Sulley et al’s perspective
study (22.4%), Macedo-de-Araújo’et al found that the top
reasons for subjects to drop out of scleral lenses were that
35% of the dropouts experienced handling issues and 19%
of the dropouts experienced ocular discomfort.
18,19
The
primary difference between Macedo-de-Araújo’et al’s
work and Sulley et al’s work is likely related to the unique
issues associated with applying scleral lenses (eg, most
scleral lens wearers need to use application devices to
apply the lens) compared to soft contact lens wearers who
typically just apply the their contact lenses with their
fingers.
19
These data suggest that early in a contact lens
wearer’s life acceptable vision is one of the most important
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factors for contact lens success while after wearing lenses
for one or more years, many contact lens wearers begin to
experience contact lens discomfort, which eventually
results in contact lens dropout.
20
These data furthermore
indicate that the frequency of contact lens dropout across
a contact lens wearers’life (neophyte vs established contact
lens wearers) is relatively stable, so contact lens practi-
tioners should be regularly monitoring for issues.
A summary of studies related to the frequency of contact
lens dropout can be found in Table 1. Data from this table
has been subsequently used to estimate an across study
frequency of contact lens dropout (pooled mean = 21.7%).
Resuming Contact Lens Wear
While investigators such as Pritchard et al and Dumbleton
et al have used surveys to investigate subjects returning to
contact lens use after dropout,
8,10
others have prospectively
studied this topic in an attempt to see if contact lens drop-
outs could successfully resume contact lens wear if given an
alternative contact lens option. Schlanger (1993) was the
first to attempt this approach by recruiting 199 subjects
from the United States who self-identified as contact lens
dropouts within the past 10 years.
21
Schlanger’s study
found that if given the option to try an alternative contact
lens, 82% of subjects could wear their contact lenses at least
on the weekends and 64.5% of subjects could wear their
contact lenses on a daily basis for at least 10 hours per day.
21
Unfortunately, this study only had a one week follow up
time period.
21
Young et al (2002) later completed a similar,
yet more comprehensive study of subjects who dropped out
of contact lenses at least one year ago.
16
Young et al’s
6-month multi-center study, which was conducted in the
United Kingdom, recruited 236 contact lens dropouts who
were refit into an alternative contact lens.
16
The top reason
subjects had originally dropped out of contact lenses was
because of discomfort (51%) and poor vision (13%). Of the
included subjects 96% of them were dispensed lenses and of
these subjects 77% of them were still wearing contact lenses
at the one-month visit.
16
Nevertheless, by the six-month
evaluation, 26% of the subject who were able to be con-
tacted (214/236) indicated that they were contact lens
dropouts.
16
Therefore, these data overall suggest that
while not all subjects are able to wear contact lenses when
given an additional opportunity, up to 74% of subjects may
be able to successfully resume contact lens wear at least part
time.
16,21
These results from Young et al’s study are similar
to Dumbleton et al’s survey of lapsed wearers study (77% vs
74%), though differences in study design (prospective vs
retrospective) and sample size (236 subjects vs 4207 sub-
jects) prevent a true comparison between studies.
10,16
Factors Associated with Contact Lens
Dropout
With over 140 million contact lens wearers worldwide and
over 45 million wearers in the United States alone, there is
clearly a high demand for contact lenses.
22,23
Unfortunately,
these numbers are relatively small in comparison to the
estimated 2.5 billion myopes in the world who could benefit
from contact lenses and the many other patients who suffer
from refractive error issues such as presbyopia who could
also benefit.
24
These data suggest that there a number of
factors that are either inhibiting patients from trying contact
lenses or from being a successful contact lens wearer. The
following section describes the known factors that are asso-
ciated with contact lens dropout (inability to succeed with
contact lenses) with hope thatfuture strategies can be devised
to help mitigate the shortcomings of contact lenses.
Patient Factors (Sex, Age)
There is limited evidence in the literature to support that
sex or age influences the frequency of contact lens drop-
out. During the above mentioned Richdale et al (n = 730)
study on contact lens dropout and dissatisfaction,
25
the
authors determined that contact lens dropout was about
two times more likely with males than females. However,
other studies have failed to show a significant association
between sex and dropping out of contact lenses. This claim
is supported by Pritchard et al (n = 1444) and Dumbleton
et al (n = 4207) who all failed to find an association
between sex and being a contact lens dropout.
8,10
The literature likewise suggests that age is another factor
that may or may not be associated with contact lens dropout.
Richdale et al found in their study of established wearers that
contact lens dropouts were more likely to be older when first
starting to wear contact lenses and more likely to have worn
lenses for a longer period in their lifetime.
25
Pritchard et al
likewise found that contact lens dropouts started wearing
lenses at an older age than successful lens wearers.
8
However, while Young et al also found contact lens dropouts
to have worn lenses for a longer time period in their lifetime,
they found conflicting evidence that contact lens dropouts
started wearing lenses at a younger age.
16
In addition, Pucker
et al did not find a difference in age when starting contact lens
wear between successful contact lens wears and contact
lens dropouts, but the authors note that successful contact
lens wears had worn lenses longer than the dropouts which
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conflicts with the results from other studies.
9
Thus, based on
the above work, there are no definitive associations between
sex nor age and contact lens dropout. Unfortunately, the data
on age is muddied by patients becoming presbyopic, which
has the potential to cause some patients to drop out of contact
lenses because of the visual changes associated with advan-
cing age.
9
Contact Lens Factors
Exploring more modifiable factors associated with contact
lens dropout has the potential to provide insight into meth-
ods for reducing the frequency of contact lens dropout. One
area of interest is the parameters of contact lenses; however,
very few direct and definitive associations have been found
between contact lens dropout and factors such as contact
lens material, modulus, and lens design. One study of note
is Pucker et al (2019) who recruited a group of subjects who
dropped out of contact lenses because of discomfort within
the past six to 12 months and compared these subjects to
successful contact lens wearers (n = 112).
9
The investiga-
tors of this study found a non-significant association (p =
0.05; odds ratio = 2.5) between hydrogel contact lens wear-
ers and silicone hydrogel contact lens wearers for contact
lens dropout. This finding is corroborated by Sulley et al
(2018) who found that material (silicone hydrogel vs hydro-
gel) had no impact on contact lens retention rates.
18
Nevertheless, the above described Dumbleton et al (2013)
study found that lapsed contact lens wearers were more
likely to wear hydrogel contact lenses than silicone hydro-
gel contact lenses,
10
and because of this there is still no
consensus on the effects of contact lens material on contact
lens dropout. The difference between Pucker et al’s,
Dumbleton et al’s, and Sulley et al’s studies that may be
leading to this lack of clarity include that Sulley et al’s work
focused on neophyte contact lens wearers whereas the other
two studies focused on established wearers.
9,10,18
Pucker
et al’s and Sulley et al’s were likewise prospective studies
while Dumbleton et al’s study was a retrospective study.
Lastly, Dumbleton et al’s study was considerably larger
than the other two studies, which may have made it easier
for these investigators to have found a significant result.
Research studies have also focused on investigating the
relationship between contact lens parameters and ocular
discomfort. There is likewise conflicting evidence showing
a relationship between contact lens discomfort and mate-
rial. Several large, cross-sectional studies have reported
either greater comfort with silicone hydrogel,
26
equal or
greater comfort to silicone hydrogel compared to
traditional hydrogel lenses,
27
or that hydrogel lenses has
less comfort or no difference in hydrogel lenses compared
to silicone hydrogel lenses.
28
Based on these studies, while
there are ocular surface health benefits from silicone
hydrogel contact lenses compared to traditional hydrogels
(eg increased oxygen transmissibility leading to less cor-
neal edema),
29
it is difficult to ascertain a significant rela-
tionship between lens material and contact lens dropout.
Nevertheless, a better understanding of how contact lens
material affects contact lens comfort and dropout would
greatly benefit the community because this knowledge
could lead to customized treatments and more biocompa-
tible materials. These advancements will likely only be
achieved by completing well-designed, prospective, rando-
mized trials that pit a number of materials against each
other and include molecular endpoints that can determine
the biological impact of individual materials.
Sphere, Toric, and Presbyopic Lenses
There may be an association between the type of refractive
lens needed and contact lens dropout. Sulley et al (2018)
reported retention rates for the first year of wear for
neophytes and found these rates to be highest in spherical
lens wearers (81%), followed by toric lenses (75%), and
multifocal lenses worn by presbyopes (69%).
18
Likewise,
Young et al reported high success rates in spherical wear-
ers, with lower rates in toric wearers followed by multi-
focal wearers.
16
These studies suggest an association
between contact lens dropout rates and refractive design
of the contact lens. Furthermore, contact lens wearers of
these different designs may report different reasons for
dropping out of contact lens wear. While new wearers of
spherical lenses may discontinue due to handling of the
lens and discomfort, those fit in toric and multifocal lenses
are more likely to discontinue due to poor vision.
16,18,30
Therefore, it may be especially important to have toric and
multifocal contact lens wearers return for a follow up visit
to ensure that all of their visual needs are being met.
Wear Schedule
Reusable contact lenses are now frequently prescribed
meaning that the contact lenses are usually worn on
a monthly or biweekly basis, removed nightly and disin-
fected with care systems, reapplied during the day, and
discarded after the wear period. Daily disposable contact
lenses are also frequently prescribed; these wearers discard
their contact lenses each day after the wear cycle. Daily
disposable contact lenses have gained popularity since
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their inception because of the many benefits of a daily
disposable contact lenses such as ease of use and increased
compliance due to the limited need for contact lens care
products like multipurpose solutions or cases.
31–33
Therefore, it seems prudent to investigate whether this
simplified modality has influenced the frequency of con-
tact lens dropout.
In a 2013 Dumbleton et al survey, 24% of the discontin-
ued contact lens wearers had worn daily disposable contact
lenses while only 19% of the successful contact lens wearers
were wearing daily disposable lenses.
10
In contrast, the same
survey found that 71% of the discontinued contact lens
wearers had worn frequent replacement soft lenses while
76% of the successful wearers wore frequent replacement
soft lenses. These results, suggesting that a higher proportion
of daily disposable lens wearers discontinued lens wear, are
surprising and may be explained by clinicians’prescribing
tendencies. Chalmers et al found that clinicians tend to pre-
scribe daily disposable contact lenses to their more challen-
ging/dissatisfied patients.
27
Therefore, more dropouts in the
daily disposable modality may have been artificially skewed
by using daily disposable lenses as a problem solver. Other
more recent studies have also investigated daily disposable
wear and contact lens dropout. A study by Sulley et al (2018)
found no difference in the one year retention rate between
new contact lens wearers wearing daily disposable lenses and
reusable lenses.
18
Pucker et al (2019) likewise evaluated
clinical factors associated with contact lens dropout and
failed to find an association between wear schedule and
being a contact lens dropout.
9
Finally, when considering
comfort as a reason for contact lens dropout, Chalmers et al
found no difference in comfort between daily disposable
and reusable contact lens wear,
30
although others report an
increase in reported comfort by reusable contact lens wearers
fit into daily disposable lenses suggesting greater comfort
with daily disposable contact lenses.
16,34
These data overall
suggests that it is currently unclear how wear schedule affects
the frequency of contact lens dropout in reusable contact lens
wearers.
Ocular Surface Factors
A contact lens placed on the eye’s surface interacts directly
with the cornea, conjunctiva, tear film, and eyelids.
35
Any
homeostatic imbalance caused by ocular surface conditions,
such as dry eye or meibomian gland dysfunction, can become
exacerbated by a contact lens and lead to contact lens dis-
comfort or contact lens-induced dry eye.
23,36
This issue as it
relates to contact lens dropout has been specifically analyzed
by Giannaccare et al (2016) via a retrospective analysis (n =
87).
37
The authors found that compared to controls, subjects
who had discontinued contact lens wear had lower/worse tear
break up time and Schirmer test values, and higher/worse
ocular surface disease index (OSDI) and corneal staining
scores. These results suggest that patients with signs of dry
eye such as quick tear film evaporation, poor tear production,
and corneal irritation may be more likely to drop out of
contact lenses.
To further elucidate clinical parameters that may be pre-
dictive of a contact lens wearer developing symptoms of
discomfort, and thus having an increased risk of dropping
out of contact lenses, Siddireddy et al enrolled 30 healthy,
established contact lens wearers and performed assessments
of ocular surface signs and symptoms.
38
The investigators
determined that worse tear film evaporation rate without
contact lenses, palpebral conjunctival staining scores, and
lid-parallel conjunctival folds were all acceptable predictors
of contact lens discomfort. Furthermore, they concluded that
evaluating the secretions of the meibomian glands (volume,
quality, and expressibility) were strong predictors of contact
lens discomfort. This agrees with Pucker et al (2019) who
concluded that those successfully wearing contact lenses had
less upper eyelid meibomian gland tortuosity whereas con-
tact lens dropouts had more meibomian gland plugging in
upper and lower eyelids and worse meibum quality in upper
eyelids than successful wearers.
9,39
Nevertheless, Pucker
et al did not find any difference in meibomian gland atrophy
grades between successful and lapsed contact lens wearers,
and they did not find any significant differences in any other
ocular surface factors such as tear break up time, tear menis-
cus height, or blepharitis when comparing successful and
unsuccessful wearers. Consequently, based on these studies,
one can conclude that evaluation of meibum quality in both
upper and lower eyelids may be predictive of intolerant
contact lens wear and that meibomian gland dysfunction
should be regularly screened for and treated when managing
contact lens wearers to help avoid contact lens dropout.
Combatting Contact Lens Dropout
Ensuring successful contact lens wear and reducing the
chances of contact lens dropout can be beneficial for both
patients and clinicians.
11
Various targeted strategies can be
used to help promote contact lens success, and these strate-
gies should be employed in at least three different timepoints
in a contact lens wearer’slife:first fitting, established wearer,
and presbyopia. At these different stages, practitioners can
employ evidenced-based strategies to target patients and help
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them avoid dropping out of contact lenses. The following
section includes strategies based on the findings of the cur-
rent review, which may be supported by mitigating factors
that can contribute to discomfort symptoms. A full descrip-
tion of treating contact lens discomfort is outside of the scope
of this manuscript, though a summary of the currently
accepted treatment methods can be found in the Tear Film
and Ocular Surface Society’s report on contact lens discom-
fort management and therapies.
40
A study by Sulley et al (2017) found that after reviewing
patient records, practitioners reported a dropout rate of 26%
at 1 year of contact lens wear with close to 50% of those
dropping out in the first two months.
17
Prior to the first fitting,
a thorough evaluation of the health of the ocular surface is
necessary to determine potential risk factors for future drop-
out. These risk factors include signs of dry eye disease and
meibomian gland dysfunction, which may increase the like-
lihood dropping out of contact lenses.
9
After fitting a patient
in a contact lens, regular follow up visits or calls can improve
retention.
17
Once the patient is an established wearer, identi-
fying that the contact lens wearer is symptomatic is the first
step in determining the likelihood of a patient dropping out of
contact lenses. Established, psychometrically validated ques-
tionnaires such as the Contact Lens Dry Eye Questionnaire
(CLDEQ)-8 or Standardized Patient Evaluation of Eye
Dryness (SPEED) can be utilized to screen patients for the
development of contact lens related dry eye and contact lens
discomfort.
41–43
However, pointed questions directed
towards discerning hours of comfortable wear time may
also prove useful in determining whether a management
strategy is needed to prevent discontinuation of lens wear.
10
With new wearers, handling and vision are primary reasons
for contact lens dropout.
18
Thus, picking lenses with an
improved edge design and higher modulus may provide
benefit.
44
Practitioners should also consider fitting patients
with low cylinder in toric lens designs to improve vision now
that they are widely available since the top complaint of
neophyte toric contact lens wearers who have dropped out
of contact lenses is poor vision.
17,18
One of the most common problems of patients struggling
with soft contact lens wear is reduced end-of-day comfort;
therefore, this topic should be regularly probed during patient
history.
14
Contact lens discomfort, encompassing symptoms
such as discomfort, dryness, irritation, fatigue, etc, is the most
common reason for contact lens dropout in established wear-
ers and addressing the contributing factors may prevent con-
tact lens dropout. Factors contributing to ocular discomfort
can include contact lens parameters such as material, design,
wear modality, and lens care solution, in addition to patient
and environmental factors like age, gender, medications, and
ocular surface health.
23
A thorough review of these factors can
be found in the Tear Film and Ocular Surface Society
International Workshop on Contact Lens Discomfort: report
of the contact lens materials, design, and care subcommittee.
45
Presbyopia is a common condition that typically char-
acterizes individuals over the age of 40 years and may
necessitate correction of vision using multifocal contact
lenses.
46
These contact lenses have varying designs to pro-
vide correction at distance, near, and sometimes intermedi-
ate ranges. Poor vision and discomfort are often the primary
reasons for discontinuation of contact lens wear in the
presbyopic population.
47–49
While there are large scale
studies that failed to show a significant difference in success
rates between presbyopic and non-presbyopic contact lens
wearers,
16
setting realistic expectations with “real world”
testing of multifocal contact lenses and using the latest
multifocal designs and materials may prove to be uniquely
successful when fitting presbyopic patients. Unfortunately,
conditions such as dry eye are more common in this group
of patients,
50
which is an additional hurdle that may pro-
mote contact lens dropout in presbyopic patients.
51
Again,
as described above, early treatment may promote additional
years of comfortable contact lens use.
9
Nevertheless, at
every state of a contact lens wearer’s life, they should be
offered an alternative contact lens option if they are strug-
gling or if they have dropped out of lenses because research
suggests that they may be able to resume contact lens
wearer if they are given additional opportunities.
16
Conclusions
Contact lens dropout is a highly prevalent condition that is
most commonly attributed to discomfort in established con-
tact lens wearers while new wearers most frequently drop-
out of contact lenses because of poor vision. While silicone
hydrogel and daily disposable lenses are now easily avail-
able to practitioners, these innovations have not altered the
frequency of contact lens dropout.
10,13,16–19
The literature
provides convincing evidence that many contact lens drop-
outs can resume contact lens wear if they are simply offered
an alternative contact lens modality; therefore, wearers
should be closely followed-up to ensure adequate contact
lens satisfaction, especially within the first two months of
contact lens wear.
17
Although factors such as age, sex, and wear schedule
do not appear to clearly influence the frequency of contact
lens dropout, meibomian gland dysfunction has been
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Clinical Optometry 2020:12
92

consistently found to promote contact lens dropout.
Therefore, it should be screened for and treated when
found to help mitigate the number of patients dropping
out of contact lenses. Overall, this review indicates that
while contact lens dropout is frequent, there are numerous
options and strategies available for combating contact lens
dropout.
Acknowledgments
No funding was specifically provided for the completion
of this work.
Commercial Relationship Disclosures
The authors have received financial support from Alcon
Research, LLC (ADP), Bausch & Lomb (ADP), Euclid
Systems (ADP), Contamac (ADP), National Eye Institute
(ADP, AAT), and Paragon Vision Sciences (ADP), and con-
sulted for Alcon Research, LLC (ADP), CooperVision
(ADP), EpiTech (ADP), EyeGate Pharmaceuticals, Inc
(ADP), and Optikal Care Inc (ADP) over the past three years.
Disclosure
Dr Andrew D Pucker reports grants, personal fees from
Alcon Research, LLC, grants from Bausch & Lomb,
grants, personal fees from Euclid Systems, grants from
Contamac, grants from National Eye Institute, grants
from Paragon Vision Sciences, personal fees from
CooperVision, personal fees from EpiTech, personal fees
from EyeGate Pharmaceuticals, Inc, personal fees from
Optikal Care Inc, during the conduct of the study. The
authors report no other conflicts of interest in this work.
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