Prevalence and risk factors for visual impairment in preschool children the sydney paediatric eye disease study
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Published on: March 17, 2023
Amy Shih-I Pai1, Jie Jin Wang, Chameen Samarawickrama
1Centre for Vision Research, Westmead Millennium Institute (Westmead Hospital), University of Sydney, Sydney, Australia.
Insights
Visual impairment affects 6.4% of Australian preschool children, primarily due to refractive errors and amblyopia. Low birthweight is a significant risk factor for childhood visual impairment.
Area of Science:
- Ophthalmology
- Pediatric Medicine
- Public Health
Background:
- Childhood visual impairment (VI) is a significant public health concern.
- Understanding the prevalence and risk factors for VI in preschool-aged children is crucial for early intervention.
- Previous studies have varied in their assessment methodologies and population focus.
Purpose of the Study:
- To determine the prevalence of visual impairment in Australian preschool children.
- To identify associations between visual impairment and demographic factors, including birth parameters.
- To investigate the primary causes of visual impairment in this age group.
Main Methods:
- A cross-sectional, population-based study was conducted involving 2461 children aged 6-72 months.
- Visual acuity (VA) was measured using the Electronic Visual Acuity (EVA) system or logMAR charts.
- Visual impairment was defined based on presenting VA, with refractive errors, myopia, hyperopia, astigmatism, and anisometropia also assessed.
Main Results:
- Visual impairment was detected in 6.4% of the worse eye and 2.7% of the better eye.
- Refractive errors (69.7%) and amblyopia (26.3%) were the leading causes of VI in the worse eye.
- Low birthweight (<2500 g) was independently associated with VI (OR 2.4), while age, gender, and socioeconomic status were not significant factors.
Conclusions:
- 6.4% of Australian preschool children exhibit visual impairment in at least one eye.
- Uncorrected refractive errors and amblyopia are the main ocular conditions contributing to VI.
- Low birthweight is a key independent risk factor for visual impairment in preschool children.
Purpose:
To assess the prevalence and associations of visual impairment (VI) in preschool children.
Design:
Cross-sectional, population-based study.
Participants:
A total of 2461 children (73.8% participation rate), aged 6 to 72 months, were examined in the Sydney Paediatric Eye Disease Study during 2007-2009; of whom 1188, aged 30 to 72 months, with complete visual acuity (VA) data in both eyes, were included in this report.
Methods:
Measurement of VA was attempted on all children using the Electronic Visual Acuity (EVA) system or a logarithm of the minimum angle of resolution (logMAR) chart. Visual impairment was defined as presenting VA <20/40 in children aged ≥48 months and <20/50 in those aged <48 months. Post-cycloplegic refraction was measured, and myopia was defined as spherical equivalent (SE) ≤-0.50 diopters (D), hyperopia was defined as SE ≥2.00 D, astigmatism was defined as cylinder ≥1.00 D, and anisometropia was defined as SE difference ≥1.00 D between 2 eyes. Ethnicity, birth parameters, and sociodemographic information were collected in questionnaires completed by parents.
Main Outcome Measures:
Visual impairment prevalence and its associations with child demographic factors and birth parameters.
Results:
Visual impairment was found in 6.4% of the worse eye and 2.7% of the better eye in our sample. Refractive errors (69.7%) and amblyopia (26.3%) were the principal causes of VI in the worse eye. Astigmatism (51.3%) and hyperopia (28.9%) were the main refractive errors causing VI. In regression analysis controlling for other factors, VI was independently associated with low birthweight of <2500 g (odds ratio 2.4, 95% confidence interval, 1.1-5.3), but not with age, gender, ethnicity, or measures of socioeconomic status (P > 0.05).
Conclusions:
Visual impairment in at least 1 eye was found in 6.4% of Australian preschool children, with bilateral VI found in 2.7%. Uncorrected refractive errors and amblyopia were the principal ocular conditions associated with VI. Low birthweight was a significant risk factor independent of age, gender, and ethnicity.
Financial Disclosure(S):
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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