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Causes of visual impairment: a retrospective study in Macedonian children

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Background: Reliable data on the prevalence and causes of visual impairment in children are necessary for developing a systematic vision screening program with valid and reliable test protocols. Purpose: The aim of the study was to investigate the prevalence, main causes, and associated factors of visual impairment among Macedonian children aged 0-18 years. Methods: This retrospective study analyzed the clinical record of 829 children, attending the department of ophthalmology from October 2013 to October 2018. The following variables were investigated: age, gender, and diagnosis. Results: The prevalence of visual impairment was statistical significance higher in girls than in boys (p<0.05), with a male to female ratio of 1/1.2 . The most frequent diagnostics were refractive errors (42.6%), ocular inflammation (20.6%), and strabismus (9%). Conclusion: In our country, data on the prevalence, magnitude, and causes of visual impairment in children are needed for planning and evaluating preventive and curative services for children, and for planning special education and low vision services.
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ISSN 0030-0675. Journal of Ophthalmology (Ukraine) - 2020 - Number 3 (494)
29
Causes of visual impairment:
a retrospective study in Macedonian children
Daniela Dimitrova-Radojichikj, Daniela Tasevska
© Daniela Dimitrova-Radojichikj, Daniela Tasevska, 2020
University Ss. Cyril and
Methodius;
Skopje (N. Macedonia)
E-mail: daniela@fzf.ukim.edu.mk
Background: Reliable data on the prevalence and causes of visual impairment in children
are necessary for developing a systematic vision screening program with valid and reliable
test protocols.
Purpose: The aim of the study was to investigate the prevalence, main causes, and associated
factors of visual impairment among Macedonian children aged 0–18 years.
Methods: This retrospective study analyzed the clinical record of 829 children, attending the
department of ophthalmology from October 2013 to October 2018. The following variables
were investigated: age, gender, and diagnosis.
Results: The prevalence of visual impairment was statistical signicance higher in girls
than in boys (p<0.05), with a male to female ratio of 1/1.2 .The most frequent diagnostics
were refractive errors (42.6%), ocular inammation (20.6%), and strabismus (9%).
Conclusion: In our country, data on the prevalence, magnitude and causes of visual
impairment in children are needed for planning and evaluating preventive and curative
services for children, and for planning special education and low vision services.
Key words:
visual impairment, causes,
prevalence
Introduction. Global estimates indicate that there are
around 19 million visually impaired (VI) children world-
wide; of these, 1.4m are blind and 17.5m have low vision.
In a recent classication by the World Health Organization
(WHO), the major cause of worldwide vision impairment
was uncorrected refractive error, approximately 12.8 mil-
lion cases (67%) [1, 2]. The prevalence of childhood VI
vary between countries, ranges from 0.3 per thousand chil-
dren in the developed countries to 1.5 per thousand in the
developing countries [3].
In the global initiative “VISION 2020 The Right to
Sight,” childhood VI and refractive error are highlighted
as a priority area [4]. However, because of the require-
ment for additional resources and expertise, along with a
general lack of authentic prevalence information, visual
impairment among Macedonian children is currently not
a priority in the planning of eye care services. Therefore,
reliable data on the prevalence and causes of VI in children
are necessary for developing a systematic vision screening
program with valid and reliable test protocols. Such data
will help to direct the application of available resources
and eorts for early detection to people who are at risk,
thereby reducing the high short- and long-term costs to the
health system and society.
The aim of the study was to investigate the prevalence,
main causes, and associated factors of visual impairment
among Macedonian children aged 0–18 years.
Material and methods
This study was conducted at the Department of Oph-
thalmology in City General Hospital 8th September, Sko-
pje, N. Macedonia. The clinical record of 829 children,
aged 0-18 years, attending the department of ophthal-
mology from October 2013 to October 2018 were in-
cluded in the study. The study adhered to the Declaration
of Helsinki.
Data analysis was carried out using SPSS version 20.0
for Windows. The dierences in prevalence between age
and sex groups were analyzed using a χ2 test. A p-value
of <0.05 was considered signicant. Also, prevalence esti-
mates of visual impairment were expressed as percentages
with 95% condence interval.
Results and discussion
The sample was divided into three groups during the
analyses by combining the age range of 0-6 years for pre-
school children, than 7-14 years for elementary school
children and 15-18 years for high school children. Accord-
ing to Table 1, it is understood that the majority of the par-
ticipants are from the groups of “15-18 years” and “7-14
years”. The ratio of the participants in the age group of
0-6 years is 9.0%. Results from statistical analyses showed
that age was signicantly associated with VI, with partici-
pants in the 0-6 age group being less likely to have VI
compared to the other age groups. Also, data from other
studies suggest that VI had a linear relationship with in-
creasing age [5]. Comparing the sexes, the prevalence of
VI was statistical signicance higher in girls than in boys
(p<0.05), with a male to female ratio of 1/1.2.
In 829 participants, refractive errors were the leading
cause of VI, accounting for 42.6%, followed by ocular in-
ammation (20.6%), and strabismus (9%) (Table 2). With
regard to the causes of VI and sex, ocular inammation
was distributed evenly between female and male study
participants (20.4% versus 20.9%), whereas refractive er-
rors were found more often in girls than in boys (44.8%
ISSN 0030-0675. Journal of Ophthalmology (Ukraine) - 2020 - Number 3 (494)
30
versus 39.9%). We also found a dierence between the
sexes, with an around 76% higher prevalence of eye in-
jures in boys, this was statistically signicant (p<0.05).
Clinical evidence suggests that refractive errors are com-
mon ophthalmic disorders in children. Also, refractive
error was the most prevalent cause of VI in our sample,
accounting for 42.6% of the total. This nding is lower to
other population-based studies, which have reported rates
of 53% to 95.6% for VI caused by ametropia [6, 7].
Conclusion
In our country, data on the prevalence, magnitude, and
causes of visual impairment in children are needed for
planning and evaluating preventive and curative services
for children, and for planning special education and low
vision services.
Reference
1. Maritto SP, Global data on visual impairment 2010. Geneva:
World Health Organization; 2012. WHO/NMH/PBD/. [Ac-
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Sudan.pdf
Table 1. Distribution of participants by age and sex
Child characteristics Girls n (%) Boys n (%) All n (%; 95% CI)* p**
All participants 456 (55.0) 373 (45.0) 829 (100.0; 0.51-0.58) <.05
Age in years
0-6 40 (8.8) 35 (9.4) 75 (9.0; 0.41-0.61)
<.05
7-14 131 (28.7) 108 (29.0) 239 (28.8; 0.48-0.61)
15-18 285 (62.5) 230 (61.6) 515 (62.2; 0.50-0.59)
* Condence intervals (CIs)
** P
values were calculated by using χ2 test
Table 2. Causes of visual impairment by sex
Rank Causes Girls
n (%)
Boys
n (%)
All
n (%; 95% CI)* p**
1 Refractive errors 204 (44.8) 149 (39.9) 353 (42.6; 0.57-0.42) <.05
2Ocular inammation 93 (20.4) 78 (20.9) 171 (20.6; 0.54-0.45) >.05
3 Strabismus 53 (11.6) 29 (7.8) 82 (9.9; 0.64-0.35) >.05
4 Eye injuries 12 (2.6) 38 (10.2) 50 (6.0; 0.24-0.76) <.05
5 Macular degeneration 22 (4.8) 22 (5.9) 44 (5.3; 0.50-0.50) >.05
6 Retinal diseases 25 (5.5) 18 (4.8) 43 (5.2; 0.58-0.41) >.05
7 Computer vision syndrome 22 (4.8) 12 (3.2) 34 (4.1; 0.64-0.35) >.05
8 Other causes 7 (1.5) 11 (3.0) 18 (2.2; 0.38-0.61) >.05
9 Amblyopia 6 (1.3) 9 (2.4) 15 (1.8; 0.40-0.60) >.05
10 Optic nerve disorders 10 (2.3) 4 (1.1) 14 (1.7; 0.71-0.28) >.05
11 Nystagmus 2 (0.4) 3 (0.8) 5 (0.6; 0.40-0.60) >.05
Total 456 (55.0) 373 (45.0) 829 (100.0)
* Condence intervals (CIs)
** P
values were calculated by using χ2 test
2. World Health Organization. Visual Impairment and Blind-
ness (2014). [Accessed 15 Februari 2020]. Available at;
http://www.who.int/mediacentre/ factsheets/fs282/en/.
3. Awan AR, Jamshed J, Khan MM, Latif Z. Prevalence
and causes of visual impairment and blindness among
school children in Muzaarabad, Pakistan. Int J Sci Rep
2018;4(4):93-8.
4. Gilbert C, Foster A. Childhood blindness in the context of
VISION 2020—the right to sight. Bull World Health Organ.
2001;79(3):227–232. Epub 2003 Jul 7.
5. Aniza I, Azmawati M N, Jamsiah M, Idayu BI, Lynn
CM. Prevalence of visual acuity impairment and its associ-
ated factors among secondary school students in Beranang,
Selangor. Malaysian Journal of Public Health Medicine.
2012;12(1):39–44.
6. He M, Zeng J, Liu Y et al. Refractive error and visual im-
pairment in urban children in southern china. Invest Ophthal-
mol Vis Sci 2004;45:793–9.
7. Naidoo KS, Raghunandan A, Mashige KP et al. Refractive
error and visual impairment in African children in South
Africa. Invest Ophthalmol Vis Sci 2003;44:3764–70.
The author declare that the research was conducted in
the absence of any commercial or nancial relationships
that could be construed as a potential conict of interest.
ResearchGate has not been able to resolve any citations for this publication.
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