AN N ALES ACADEMI AE MEDI CAE S TETI N EN S I S
ROCZN I KI POMORS KI EJ AKADEMI I MEDYCZN EJ W S ZCZECI N I E
2011, 57, 3, 88 92
DAMIAN A. CZEPITA, MARIA ŻEJMO1
EN VIRON MEN TAL FACTORS AN D MYOPIA
CZYNNIKI ŚRODOWISKOWE A KRÓTKOWZROCZNOŚĆ
Studia Doktoranckie Wydziału Humanistycznego Uniwersytetu Szczecińskiego
ul. Ogińskiego 16/17, 71-431 Szczecin
Kierownik: prof. dr hab. Maria Czerepaniak-Walczak
1
Katedra i Zakład Mikrobiologii i Immunologii Pomorskiego Uniwersytetu Medycznego w Szczecinie
al. Powstańców Wlkp. 72, 70-111 Szczecin
Kierownik: prof. dr hab. n. med. Stefania Giedrys-Kalemba
Streszczenie Results: In the existing works it was demonstrated that
environmental factors lead to higher prevalence of myopia.
Wstęp: Celem pracy było dokonanie oceny wpływu It is assumed that the higher incidence of myopia in people
czynników środowiskowych na częstość występowania living in the city and in individuals with higher levels of
krótkowzroczności. education is a consequence of intensive visual near work,
Materiał i metody: Przedstawiono oraz omówiono especially in reading, writing and visual work at the com-
współczesne piśmiennictwo na temat środowiskowego puter. This dependence may be associated with changes in
uwarunkowania krótkowzroczności. the shape of the cornea or accommodation.
Wyniki: W dotychczasowych pracach wykazano, że czyn- Conclusions: Environmental factors influence the prev-
niki środowiskowe prowadzą do częstszego występowania alence of myopia. Most probably it is the consequence of
krótkowzroczności. Przyjmuje się, że częstsze występowanie intensive visual near work: reading, writing, visual work
krótkowzroczności u osób mieszkających w mieście oraz at the computer.
u osób z wyższym poziomem wykształcenia jest następ-
stwem intensywnej pracy wzrokowej do bliży, a zwłaszcza K e y w o r d s: environmental factors - myopia.
czytania, pisania oraz pracy wzrokowej przy komputerze.
Zależność ta może być związana ze zmianami kształtu
rogówki lub akomodacji. Introduction
Wnioski: Czynniki środowiskowe wpływają na częstość
występowania krótkowzroczności. Prawdopodobnie jest Myopia was rare in the past [1]. Recently, a consider-
to następstwem intensywnej pracy wzrokowej do bliży: able increase in the frequency of myopia occurrence was
czytanie, pisanie, praca wzrokowa przy komputerze. observed. The mentioned refractive error is more frequent
in East Asia and countries with a high level of technologi-
H a s ł a: czynniki środowiskowe - krótkowzroczność. cal development. This can be associated on one hand with
genetic predispositions as on the other with the influence
of the environment [2, 3].
Summary Near visual work which is reading, writing and working
on the computer play significant roles among the environ-
Purpose: The aim of the work was to assess the impact mental factors. It is assumed that different environmental
of environmental factors on the prevalence of myopia. factors such as if we live in a city or a village play a less
Material and methods: The work presents and discusses important role in the formation and progress of myopia.
contemporary literature on the environmental determinants Thus, not much regard has been focused on them [2, 3,
of myopia. 4, 5].
ENVIRONMENTAL FACTORS AND MYOPIA 89
Myopia has an important clinical significance as it can Australia as Wensor et al. [21] have shown. However, the
lead to low visual acuity or even blindness. That is why the results were most likely so because the authors examined
high need for all clinical investigations concerning the devel- subjects in the ages of 40-98 years but not school age chil-
opment of the eye and the creation of refractive errors [2, 3]. dren. Although, a more frequent occurrence of myopia was
Hence, the objective of this paper is to describe the observed among people with higher education, clerks, pro-
influence of environmental factors on the development of fessionals, people born in southeast Asia, and people with
myopia. high degrees of nuclear opacity.
In general the majority of authors come to comparable
conclusions and state that myopia occurs less frequently in
Material and methods provincial than in metropolitan schools. It is believed that
this is the reason of more intensive near-work among urban
The work presents and discusses contemporary litera- than rural schoolchildren [6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
ture on the environmental determinants of myopia. 16, 17, 18, 19, 20, 21, 22] (tab. 1).
T a b l e 1. Prevalence of myopia among schoolchildren
T a b e l a 1. Częstość występowania krótkowzroczności wśród uczniów
Myopia in the city and countryside
Myopia (%)
Authors Country Area
Krótkowzroczność
Autorzy Kraj Środowisko
Despite the fact that environmental conditions greatly
(%)
influence the creation and progress of myopia so far not
Maul et al. urban
Chile 6.8
many works were published that compare the prevalence
2000 [14] miejskie
of myopia in the city and in the countryside [6, 7, 8, 9, 10,
Pokharel et al. rural
Nepal 1.2
2000 [18] wiejskie
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22].
Zhao et al. China rural
In 1963-1983 in India the first studies regarding this
16.2
2000 [22] Chiny wiejskie
matter have been conducted. The obtained results of those
Dandona et al. India rural
studies show that the occurrence of myopia is more fre-
4.1
2002 [7] Indie wiejskie
quent among the urban population and people with higher
Murthy et al. India urban
7.4
income and education [15].
2002 [16] Indie miejskie
In 1970 Said et al. [19] reported the prevalence and
South suburban/urban
Naidoo et al.
causes of blindness in rural and urban areas of Egypt. All
Africa podmiejskie/ 2.9
2003 [17]
together they had examined 10,984 people from and around RPA miejskie
He et al. 2004 China urban
the area of Alexandria. They were able to prove that myopia
35.1
[10] Chiny miejskie
is less frequent in the countryside than in the city and that it
Goh et al. Malaysia urban
is the third ranking cause of blindness among urban residents.
19.3
2005 [9] Malezja miejskie
From 1983 to 2000 in Taiwan considerable epidemio-
Czepita et al. Poland urban
logical studies on the prevalence of myopia were carried 13.9
2008 [5] Polska miejskie
out. In all 45,359 students have been examined and it was
Czepita et al. Poland rural
7.5
observed that myopia occurs more frequently in metropoli-
2008 [5] Polska wiejskie
tan than in provincial schools located in Taiwan. Such cor-
relation was justified by much near-work activity carried
out by students of the schools in the city [6, 11, 12].
In 1999-2001 obtained results of several studies con- Myopia and education
ducted in urban and rural areas of China, Nepal and the
Sultanate of Oman were published. It was discovered that It has long been known that reading and writing leads
myopia occurs more frequently in students from the city to a higher occurrence of myopia. Nevertheless, in 1907
than from the countryside and is linked to intensive near- Fleischer [1] launched research on the effects of educational
-work as well as having a father with higher levels of edu- level on myopia and observed that in Tuebingen, Germany
cation [8, 13, 20]. 7.5% of students had myopia.
Within recent time a series of population-based surveys From Newfoundland Richler and Bear [23] after exam-
of refractive errors and visual impairment among school- ining 971 people aged 5 years and above showed that the
children (refractive error study in children  RESC) were level of education and near visual work lead to a higher
carried out in several various countries, all using the same occurrence of myopia.
protocol. The outcome of the studies present that myopia Slightly differing results were obtained by Ashton [24],
has a lesser prevalence among rural schoolchildren than after examining 723 families living in Hawaii. According
urban students [7, 9, 10, 14, 16, 17, 18, 22]. to his results higher levels of education lead to a higher
There was no great difference in myopia rates between occurrence of myopia. Nonetheless, he did not observe the
urban and rural populations in studies undertaken in relationship between near work and myopia.
90 DAMIAN A. CZEPITA, MARIA ŻEJMO
T a b l e 2. Dependence between education and myopia
occurrence of myopia. After examining 7,950 men 18 years
T a b e l a 2. Zależność pomiędzy wykształceniem a krótkowzrocznością
old appearing before the draft board in eastern Denmark,
they have found that myopia is more common in people
Dependency between educa-
with higher education. Nevertheless, the data was not sta-
Authors Country tion and myopia / Zależność
Autorzy Kraj pomiędzy wykształceniem tistically significant.
a krótkowzrocznością
Saw et al. [27] among 429 18 23-year-old military con-
Richler and Bear 1980 Canada
scripts from Singapore discovered that myopia is more com-
+
[23] Kanada
mon in people with higher education, which they explained
U.S.A.
by the increased near vision workload and the influence of
Ashton 1985 [24] +
USA
genetic factors.
Rosner and Belkin Israel
+
In 2008 Konstantopoulos et al. [28] published stud-
1987 [25] Izrael
ies on the impact of educational level on the occurrence
Teasdale and Denmark
-
of myopia. For the study the researchers examined 200
Goldchmidt 1988 [26] Dania
Singapore 17 31-year-old Greek conscripts and showed that those with
Saw et al. 2001 [27] +
Singapur
higher education tend to have myopia (tab. 2).
Konstantopoulos et al. Greece
+
2008 [28] Grecja
Myopia and reading, writing, computer, television
In 1987 the most widely-ranging research concerning
the topic was conducted by Rosner and Belkin [25]. The Currently, it is believed that people with higher edu-
authors studied 157,748 17 19-year-old Israeli male recruits. cational level have a higher occurrence of myopia which
They demonstrated that an increase in the level of educa- is the result of intensive visual work, especially of reading,
tion leads to increased prevalence of myopia. writing and visual work at the computer.
In 1988 Teasdale and Goldschmidt [26] carried out Correlation between reading and writing and the occur-
extensive research on the impact of educational level on the rence of myopia has been demonstrated in the works carried
T a b l e 3. Dependence between reading, writing, working on a computer, watching television, and myopia
T a b e l a 3. Zależność pomiędzy czytaniem, pisaniem, pracą na komputerze, oglądaniem telewizji a krótkowzrocznością
Dependence between working
Dependence between reading, Dependence between watching
on a computer and myopia
Authors Country writing and myopia television and myopia
Zależność pomiędzy
Autorzy Kraj Zależność pomiędzy czytaniem, Zależność pomiędzy oglądaniem
pracą na komputerze a
pisaniem a krótkowzrocznością telewizji a krótkowzrocznością
krótkowzrocznością
Sweden
N yman 1988 [37] -
Szwecja
Wong et al. 1993
Hong Kong +
[29]
Toppel and N euber Germany
-
1994 [39] Niemcy
Rechichi and Italy
-
Scullica 1996 [38] Włochy
Cole et al. 1996
Australia +
[35]
Mutti and Zadnik U.S.A.

1996 [36] USA
Kinge et al. 2000 Norway
+
[30] Norwegia
Saw et al. 2001 China
+
[27] Chiny
Mutti et al. 2002 U.S.A.
+
[31] USA
Loman et al. 2002 U.S.A.
-
[34] USA
Saw et al. 2006 Singapore
-
[32] Singapur
Jones et al. 2007 U.S.A.
- 
[33] USA
Czepita et al. 2010 Poland
+ + 
[4] Polska
ENVIRONMENTAL FACTORS AND MYOPIA 91
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