Glycative Stress Research
Online edition : ISSN 2188-3610
Print edition : ISSN 2188-3602
Received : July 1, 2022
Accepted : August 2, 2022
Published online : September 30, 2022
doi:10.24659/gsr.9.3_112

Original article

Presbyopia progression during the pandemic of COVID -19:
Accelerated senescence?
Masahiko Ayaki 1, 2), Kazuno Negishi 1)
1) Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
2) Otake Eye Clinic, Yamato, Kanagawa, Japan

Abstract

Objective: To compare the degree of presbyopia in ophthalmology patients before and after the 2020 COVID-19 pandemic.
Methods: Near add power measurements and dry eye-related tests were performed on 349 ophthalmology patients aged
40-55 years from 2017 to 2022, and the presence of common subjective symptoms (fatigue, blurred vision, glare, dryness,
discomfort, and pain) was interviewed. The subjects were first-visit patients with biocular phakic and best corrected visualacuity of 0.8 or better in both eyes. Patients with glaucoma, ocular fundus diseases, and those within one month after
ophthalmic surgery were excluded.
Results: From 2017-2019, near add power was strongly correlated with age ( β = 0.777, p < 0.001), and the estimated age of
onset of presbyopia was 36.5 years, which decreased to 25.5 years in 2020 and recovered to 32. 5 years in 2021. Subjective
symptoms continued to worsen in both 2020 and 2021. Tear film breakup time, a dry eye-related test, and corneal damage,remained unchanged after 2020.
Conclusion: The COVID-19 pandemic reduced the age of onset of presbyopia in 2020, indicating a decline in amplitude ofaccommodation, which recovered in 2021. Accommodation fatigue from increased near work (work that requires prolonged
close-up viewing) due to increased telework and stress from changes in lifestyle and work environment are thought to be themain causes, however, we also consider the possibility that COVID -19 may accelerate aging.

KEY WORDS: COVID -19, aging, presbyopia, eye strain, dry eye

Introduction
In March 2020, the World Health Organization declared
COVID -19 a pandemic 1) and a state of emergency was
declared in Japan in April. This led to a rapid change in workand lifestyle, with voluntary refraining from going out of thehouse, encouraging telework (telecommuting), and switching
to e-learning and distance learning 2). Along with reports ofocular complications from the virus 3), survey results reported
increased VDT (visual display terminal) viewing time, eyestrain and dry eyes 4-8), and recently worsening myopia has
also been reported in other countries 9). However, there are
few reports of studies examining changes in general ocularsymptoms and ophthalmologic examinations before and after
the pandemic.
The current study focused on subjective symptoms,
dry eye-related corneal and lacrimal tests, and near add
power, which indicates the degree of presbyopia, in first-visit

ophthalmology patients before and after the pandemic
declaration. Presbyopia makes it difficult for people to focus
on near objects as they age and interferes with their daily
lives 10). In today's society, the need for near vision is increasing
in both work and daily life, and there are far more importantsources of visual information in the near position than in thefar position. Moreover, presbyopia is becoming a serious
social problem due to the super-aging of society and the useof smartphones and other digital devices. Presbyopia is adeterioration of the accommodative function for focusing,and among the ocular tissues involved in accommodation,
the lens and pupil play a major role in presbyopia.
When we want to see near, the pupil contracts and theciliary muscle contracts to thicken the lens to focus on thenear. The ability to adjust the pupil decreases with age fromaround age 10, and most people reach a plateau of presbyopia

Correspondece to: Masahiko Ayaki MD, PhD
Department of Ophthalmology, Keio University School of Medicine
35 Shinanomachi, Shunjuku-ku, Tokyo 160-8585 Japan
TEL : +81-3-3353-1211 FAX : +81-3-3359-8302
e-mail: mayaki@olive.ocn.ne.jp

Glycative Stress Research 2022; 9 (3) : 112-117(c) Society for Glycative Stress Research_ 112 _Glycative Stress Researchby age 60. The average age at which near vision correction
becomes necessary is 48 years 11). The most common methodof correcting presbyopia is eyeglasses, in which lenses areused to correct for the lack of accommodation, which is thenear add power. Bifocal contact lenses are also used, and in
surgical treatment, a bifocal or multifocal intraocular lens isinserted during cataract surgery to treat presbyopia. In drug
therapy, the effectiveness of anti-cataract drugs has beenreported 12) and anti-oxidative/anti-glycative foods may bealso beneficial to presbyopia via anti-cataract effect 13, 14). Eye
exercise to supress the progression of presbyopia has also
been reported 15).
Presbyopia has a very large target population andincludes the working age population, so the impact on theirlives and the economy is very large. It is estimated that
1.8 billion people, or 25 % of the world's population, havepresbyopia, and 830 million people have difficulty performing
near work (work that requires prolonged close-up viewing)
due to inadequate correction 16). Other reports have shownthat up to 90 % of people over the age of 35 had presbyopia
symptoms, and presbyopia reduced quality of life scoresby up to 22 % 17). Twelve percent of people with presbyopia
needed assistance in daily life, and had a tendency toward
depression and decreased self- confidence. The loss of
productivity due to presbyopia in the under -50 age group
was $11 billion worldwide, equivalent to 0.016 % of the
global gross domestic product in 2011.
In our prior study, 219 healthy subjects between theages of 40 and 59 years were measured for near add power,
and the results showed no difference between men andwomen, and no difference in the progression of presbyopia
between them 11). However, there was a significant differencein the power of contact lenses for distance vision, withwomen using an average of 0.25 D lower correction to seeboth distance and near vision. According to the results of a
web-based survey of healthy subjects aged 40 to 59 years,
presbyopia symptoms developed more strongly and earlier
in men, and men started using reading glasses an average of
9 months earlier than women (47.4 years for men and 48.2
years for women).
Men who used reading glasses had lower well-being,
men who were aware of presbyopia symptoms had poorer
sleep, and this was not the case for women. It is assumed thatthe reason why men suffer more from presbyopia symptoms
is because men have more opportunities to look at distantobjects and women at near objects in their work and daily
life. Recent studies have shown that near vision impairment
due to presbyopia occurs from the stage when binocular nearvisual acuity is as good as 1.0, so it is necessary to establish
new diagnostic criteria for presbyopia in order to diagnose
presbyopia and provide appropriate therapeutic intervention 18).
The COVID -19 pandemic has led to widespread
telecommuting and distance learning, resulting in an increasein the amount of time spent working on the web using VDT,
and a larger number of people are complaining of eye strain.
We previously conducted a study of 339 ophthalmology
outpatients aged 40-55 years in 2017, 2019, and 2020-2021,
before and after the pandemic, to determine the the degree ofpresbyopia (near add power) increased after the pandemic 19).
The degree of presbyopia usually shows a strong correlation
with age, but after the pandemic declaration, the correlation
was weaker. Since then, there have been no reports examining

the relationship between the pandemic and eye strain orpresbyopia. Our study therefore aimed to compare thesymptoms and clinical examination results of ophthalmology
patients before and after the pandemic declaration, and to
examine the course of the disease after the declaration in2020 and 2021.

Methods
The study was a retrospective, cross-sectional cohort
study and was approved by the Institutional Review Boardof Keio University School of Medicine, Tsukuba Central
Hospital, and Kanagawa Medical Association. Consent ofstudy participants was obtained on an opt-out basis, and thestudy was conducted in compliance with the Declaration of
Helsinki and ethical guidelines for clinical research.
The subjects were patients who visited Otake Eye Clinic(Yamato, Kanagawa, Japan) and Tsukuba Central Hospital(Ushiku, Ibaraki, Japan) from 2015 to 2021 and met the
selection criteria. The selection criteria were first-visit patientswith binocular phakic, age between 40 and 55 years, and withcorrected visual acuity of 0.8 or better. Exclusion criteria were
glaucoma, vitreoretinal disease, optic nerve disease, acuteocular disease occurring within 2 weeks, and ocular surgery
within one month of data collection. The reason for selecting
this age range is that presbyopia generally progresses linearly
during this period, and it is possible to examine the effectsof various conditions. Glaucoma was excluded from thisstudy, since glaucoma eye drops have the effect of decreasing
accommodation 20).
Examinations included a corrected visual acuity anda near add power test (using the New Standard Near Vision
Chart manufactured by Handaya, Tokyo, Japan). Corneal
examinations included fluorescein corneal staining (negative
staining was classified as 0, followed by 1 and 2 in orderof degree) and tear film breakup time (BUT). Symptoms
were evaluated by asking about the presence or absenceof six common symptoms (dry sensation, foreign bodysensation, painful or sore eyes, ocular fatigue, blurred vision,and sensitivity to blight light) extracted from the DEQS
(Dry Eye-related Quality-of-Life Score) 21), a standardized
questionnaire for dry eyes.
Statistical analysis was performed by dividing cases into
three groups by year of examination (2017-2019, 2020, and2021) and comparing pre- and post-pandemic cases using
the Mann-Whitney test with Bonferroni correction, and chisquare test for frequency of symptoms. Correlation analysis
with age in each group was performed for near add power,
and the correlation coefficients and presbyopia progression
were compared before and after the pandemic. Regression
equations were obtained using the least squares method.
Statistical software StatFlex (Artec, Osaka, Japan) was used.

Results
The number of cases in each group, gender, refraction,near add power, progression of presbyopia, and correlation
coefficient between age and near add power are shown in_ 113 _

Presbyopia Progression during the Pandemic of COVID -19

Table 1. Spherical equivalent became more myopic with eachyear of age. The mean near add power for the entire subject
population was 1.54 ± 0.67 D in 2017-2019 before thepandemic, then 1.79 ± 0.55 D in 2020 (p = 0.003, vs 20172019), and 1.71 ± 0.65 D (p = 0.039).
The degree of presbyopia progression by age increased
in 2020 compared to 2019 (p < 0.001) and recovered in 2021
(p = 0.104). The correlation coefficient with age also decreased
in 2020 (p < 0.001), then recovered in 2021 (p = 0.106). Scatterplots and regression lines for the three groups are shown in
Fig. 1, where the x-intercept at y = 0 can be considered theapproximate age of onset of near add power, 36.5 years in
2017-2019 (regression equation; y = 0.128x − 4.70), 25.5 years
in 2020 (y = 0.074x − 1.89, p < 0.001, vs 2017-2019) and 32.5
years in 2021 (y = 0.104x − 3.39, p = 0.074). After the pandemic
declaration, the age of presbyopia onset shifted significantly
to the younger side and recovered in 2021.
After the pandemic, subjective symptoms generally
worsened in 2020 and 2021, except for eye pain, which
did not differ significantly (Table 2, Fig. 2 ). Both BUT andcorneal staining score did not change before and after the
pandemic.

Table 1. Refraction and presbyopia status.
Year

2017-2019

2020

225

n

26.2

Sex (% male)48.9 ± 4.7

49.5 ± 3.7− 3.80 ± 3.12

Spherical Equivalent (D)626248.5 ± 4.1

Age

P value
P value(2017-2019 vs 2020) (2017-2019 vs 2021)

2021

35.3

− 2.81 ± 2.97

23.0

− 2.52 ± 3.11

0.032*

0.257

0.152

0.625

0.011*

0.002*

1.79 ± 0.55

1.71 ± 0.65

0.003*

0.039*

0.13

0.07

0.10

< 0.001*

0.104

Standardized correlation coefficient
between age and near add power

0.787

0.503

0.687

< 0.001*

0.106

Estimated age at zero near add
power (y)

36.5

25.5

32.5

< 0.001*

0.074

1.54 ± 0.67

Near add power (D)Progression of presbyopia (D/y)* p < 0.05, calculated by Mann Whitney U test with Bonferroni correction except for sex, which was analyzed with chi square test.

Near add power (D)320172019

3

2

1

3

2020

2.5

2.5

2

2

1.5

1.5

1

1

0.5

0.5

2021

0
20

30

40

Age (y)

50

60

20

30

40

Age (y)Fig. 1. Scatter plots of near add power and age in each group.

50

60

20

30

40

50

Age (y)Scatter plots and regression lines of patient age and near add power for each year are shown. The x-intercept at y = 0 can be considered
the approximate age of occurrence of near add power, shifting significantly to the younger side after the pandemic declaration andrecoverying in 2021.

_ 114 _

60

Glycative Stress Research

Table 2. The prevalence of dry eye-related symptoms and corneal signs.
Year and prevalence (%)

2017-2019

Eye fatigue

46.6

2020

3.00 ± 2.22

2.73 ± 2.22

0.28 ± 0.52

0.21 ± 0.54

0.29 ± 0.57

Positive corneal staining

11.9

22.4

2.99 ± 2.04

Tear break-up time

25.4

20.9

10.0

Pain

39.0

34.3

16.8

Discomfort

23.7

23.9

22.1

Dryness

54.2

43.3

18.3

Photophobia

52.5

46.3

43.1

Blurring

2021

P value(2017-2019 vs 2020)

P value(2017-2019 vs 2021)

0.863

0.445

0.964

0.131

0.309

0.309

0.103

0.059

0.464

0.160

0.011*

0.657

0.723

1.000

0.558

1.000

*p < 0.05, chi squared test and Mann-WhitneyU test with Bonferroni correction

Dryness

60

Fatigue
Photophobia

Prevalence (％)

50

Pain
Discomfort

40

Blurring

30

20

Fig. 2. Prevalence of ocular symptom ineach group.

100

2017-20192020

Changes in the frequency of major ocularsymptoms before and after the pandemic
are shown. With the exception of eye
pain, there was a worsening trend in 2020
and 2021 after the pandemic declaration,
while the difference was not significant
compared to 2017-2019.

2021

Year

Discussion

The present study showed that the degree of presbyopia
worsened after the pandemic was declared. In other words,
the age at which presbyopia began to require near correction
was earlier, and this trend eased in 2021, one year after
the pandemic was declared. The reasons for the increasein near add power after the pandemic declaration may be
due to accommodation fatigue and stress associated withincreased VDT viewing time. Studies have reported thatstress increases pupil diameter and decreases amplitude ofaccommodation 22-24). In particular, it is imagined that many
people were anxious and stressed immediately after the
pandemic was declared.
In general, there is a strong correlation between age andnear add power, as in the pre-pandemic 2017-2019 values.
Nevertheless, in 2020, the correlation varied. We speculatethat the reason for this is that there are individual differencesin ocular fatigue and stress-induced decline of accommodation
under the pandemic.
The fact that the x-intercept of the regression line was
as young as 25.5 years old indicates that there was a marked
decline in the subject's overall amplitude of accommodation
and age at which presbyopia began. By 2021, both thecorrelation coefficient and the x-intercept values wereapproaching pre-pandemic levels. This may mean that thetarget patients are becoming accustomed to their new lives
and jobs, while the number of companies promoting telework
continues to increase,
Nevertheless, it is worth noting that the pandemic
significantly affected the accommodative function of the eye
and accelerated the age of onset of presbyopia by 10 years.
Besides the increase in near work and stress, there is also
the possibility of an epigenetic aging-promoting effect of_ 115 _

Presbyopia Progression during the Pandemic of COVID -19

COVID-19, since a certain percentage of the target patientsare thought to have been COVID-19-infected 25, 26). Presbyopia
is a typical aging phenomenon that progresses at a certain
rate, and the fact that marked changes were observed after
the pandemic this time may be a useful result in considering
the systemic effects of this virus.
Subjective symptoms took a different course thanpresbyopia; they were worse in 2020 than in 2019, as expected,
but the worsening trend continued in 2021. This may be dueto the fact that presbyopia symptoms, eyestrain symptoms,
and dry eye symptoms continued and that patients who had
refrained from going out gradually began to see the doctor,
which may have resulted in a change in the subject content 27).
There is concern that dry eye may increase during apandemic due to stress and the constant wearing of masks 28, 29).
Dry eye causes instability of the tear fluid layer on the ocularsurface, resulting in a variety of symptoms including dryness,foreign body sensation, pain, fatigue, blurred vision, andphotophobia 30, 31). Epidemiologically, the frequency of dry
eye is higher in women and the elderly, while the incidenceof dry eye has been increasing in recent years, as blinking
is believed to worsen or develop when looking at digital
screens. When the precorneal tear film, which is part of the
optical system, is disrupted by dry eye, visual function is
reduced, and higher order aberrations and reduced functional
visual acuity have been reported 32-35). Our study revealed
that presbyopia progresses significantly faster in female
dry eye patients 36), which may be related to the present
results. Since the BUT, a major indicator of dry eye, did notchange, it is possible that the accommodation fatigue due toincreased near work may be a more significant factor in thedeterioration of presbyopia at this time. On the other hand,some people find telecommuting stressful while others do
not. The work environment also differs from that of those
who go to work. With the advantages of free air conditioning
and the ability to work without a mask, whether teleworking
is a factor that aggravates dry eye needs further study.

Research limitation
First, the eye examination patients analyzed in thisstudy may be biased toward those with severe symptoms tosome extent. Especially after 2020, many patients who daredto visit a doctor because of concerns about their symptoms
are included in this group, even though they are refraining
from going out. If the general public aged 40-55 were
included in the analysis, the impact of the pandemic could be
more accurately assessed. Concurrently, during the period of
the emergency declaration and “the Law for the Preventionof the Spread of Infectious Diseases”, many people are likely
to refrain from seeing a doctor, especially the elderly andpatients with minor illnesses. The situation of consultations
differs from that before the pandemic, which is also likely to
be biased.
Second, we did not investigate previous infection
associated with the pandemic or COVID-19 virus antibody
levels, and the infection status of the subjects was unknown.
Therefore, the effect of COVID-19 infection on presbyopia
could not be examined in this study.
Third, further measurement of pupil diameter, which
is significantly involved in accommodation, would allow
accurate evaluation of presbyopia status. In addition, bylistening to the duration of VDT viewing and the use of digital
devices, it is possible to clarify the relationship between thenear add power and the symptoms.

Conflict of interest declaration
The authors have no conflicts of interest to declare.

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